1 00:00:05,080 --> 00:00:10,280 WELCOME TO THE LECTURE IN THE 2 00:00:10,280 --> 00:00:14,360 BIOMEDICAL GROUP. 3 00:00:14,360 --> 00:00:18,000 PLEASE ASK ANY QUESTIONS VIA THE 4 00:00:18,000 --> 00:00:19,640 NIH VIDEOCAST SYSTEM, LIVE 5 00:00:19,640 --> 00:00:20,600 FEEDBACK BUTTON, QUESTIONS 6 00:00:20,600 --> 00:00:24,000 ROUTED TO SPEAKER AT THE END. 7 00:00:24,000 --> 00:00:27,840 I'LL HAND IT OVER TO OUR 8 00:00:27,840 --> 00:00:30,480 CO-HOST, DR. MATT WOLF, FOR 9 00:00:30,480 --> 00:00:32,160 INTRODUCTION OF OUR SPEAKER. 10 00:00:32,160 --> 00:00:34,200 >>ALL RIGHT. 11 00:00:34,200 --> 00:00:35,240 THANK YOU VERY MUCH, CAITLIN. 12 00:00:35,240 --> 00:00:39,000 TODAY IT IS MY PLEASURE TO 13 00:00:39,000 --> 00:00:41,880 INTRODUCE DR. DAVE MOONEY. 14 00:00:41,880 --> 00:00:44,960 DR. MOONEY IS THE FAMILY 15 00:00:44,960 --> 00:00:46,160 PROFESSOR OF BIOENGINEERING AT 16 00:00:46,160 --> 00:00:47,360 HARVARD UNIVERSITY, A FOUNDING 17 00:00:47,360 --> 00:00:50,480 CORE FACULTY AND LEAD OF THE 18 00:00:50,480 --> 00:00:53,880 IMMUNOMATERIALS FOCUS AREA AT 19 00:00:53,880 --> 00:00:56,000 THE WYSS INSTITUTE FOR 20 00:00:56,000 --> 00:00:56,800 BIOLOGICALLY INSPIRED 21 00:00:56,800 --> 00:00:58,280 ENGINEERING, PUBLISHED HUNDREDS 22 00:00:58,280 --> 00:01:00,280 OF PAPERS, AMASSED NUMEROUS 23 00:01:00,280 --> 00:01:01,480 HONORS OVER HIS CAREER, 24 00:01:01,480 --> 00:01:04,800 INCLUDING MEMBERSHIP IN SEVERAL 25 00:01:04,800 --> 00:01:06,320 OF THE NATIONAL ACADEMIES, 26 00:01:06,320 --> 00:01:08,280 INCLUDING ACADEMIES OF 27 00:01:08,280 --> 00:01:09,040 ENGINEERING, MEDICINE, 28 00:01:09,040 --> 00:01:09,520 INVENTORS. 29 00:01:09,520 --> 00:01:12,320 HIS WORK HAS HAD TRANSLATIONAL 30 00:01:12,320 --> 00:01:13,840 IMPACT, WITH NUMEROUS PATENTS, 31 00:01:13,840 --> 00:01:16,000 AND INVENTIONS THAT HAVE BEEN 32 00:01:16,000 --> 00:01:18,000 LICENSED BY OVER 15 COMPANIES 33 00:01:18,000 --> 00:01:23,040 AND LEADING TO COMMERCIALIZED 34 00:01:23,040 --> 00:01:23,960 PRODUCTS. 35 00:01:23,960 --> 00:01:28,080 SO, DR. MOONEY'S LABORATORY IS 36 00:01:28,080 --> 00:01:29,200 MULTI-DISCIPLINARY IN THEIR 37 00:01:29,200 --> 00:01:32,800 APPROACH TO USE BIOMATERIALS TO 38 00:01:32,800 --> 00:01:34,440 MANIPULATE BIOLOGICAL SYSTEMS. 39 00:01:34,440 --> 00:01:38,040 HOW YOU'VE HEARD OF HIM DEPENDS 40 00:01:38,040 --> 00:01:40,160 ON YOUR FIELD OF BIOENGINEERING 41 00:01:40,160 --> 00:01:41,240 STUDY, HE'S HAD AN IMPACT. 42 00:01:41,240 --> 00:01:45,600 I FIRST GOT TO LEARN ABOUT HIS 43 00:01:45,600 --> 00:01:48,000 WORK IN MUSCULOSKELETAL ISSUE 44 00:01:48,000 --> 00:01:49,520 ENGINEERING AND REGENERATIVE 45 00:01:49,520 --> 00:01:50,000 MEDICINE. 46 00:01:50,000 --> 00:01:53,360 LATER ON, I GOT TO KNOW MORE 47 00:01:53,360 --> 00:01:56,120 ABOUT HIS WORK IN IMMUNE 48 00:01:56,120 --> 00:01:56,640 ENGINEERING, CANCER 49 00:01:56,640 --> 00:02:00,840 IMMUNOTHERAPY, MECHANIC -- MECH. 50 00:02:00,840 --> 00:02:02,560 HE WILL BE TALKING ABOUT A 51 00:02:02,560 --> 00:02:03,560 DIVERSE SET OF INTERESTS TODAY 52 00:02:03,560 --> 00:02:08,680 AND I'M EXCITED TO HAND THAT 53 00:02:08,680 --> 00:02:12,240 OVER AND START HIS TALK. 54 00:02:12,240 --> 00:02:14,480 THANK YOU VERY MUCH FOR THE 55 00:02:14,480 --> 00:02:15,880 OPPORTUNITY TO COME AND 56 00:02:15,880 --> 00:02:18,080 PARTICIPATE IN A SEMINAR SERIES, 57 00:02:18,080 --> 00:02:20,280 I GREATLY APPRECIATE THE 58 00:02:20,280 --> 00:02:21,200 INVESTIGATOR FOR TAKING TIME TO 59 00:02:21,200 --> 00:02:23,240 TALK WITH ME ABOUT THE RESEARCH, 60 00:02:23,240 --> 00:02:25,400 A LOT OF EXCITING RESEARCH AND 61 00:02:25,400 --> 00:02:26,040 DEVELOPMENT IN BIOENGINEERING 62 00:02:26,040 --> 00:02:27,600 UNDERWAY AT THE NIH. 63 00:02:27,600 --> 00:02:28,560 IT'S GREAT TO SEE. 64 00:02:28,560 --> 00:02:29,760 I'M GOING TO TALK ABOUT ONE 65 00:02:29,760 --> 00:02:31,960 ELEMENT OF THE WORK IN THE 66 00:02:31,960 --> 00:02:33,040 LABORATORY TODAY. 67 00:02:33,040 --> 00:02:35,600 THAT RELATES TO EXTRACELLULAR 68 00:02:35,600 --> 00:02:36,680 MATRIX VISCOELASTICITY AND 69 00:02:36,680 --> 00:02:41,240 INTERSECTION WITH BIOLOGY OF 70 00:02:41,240 --> 00:02:41,640 CANCER. 71 00:02:41,640 --> 00:02:43,040 BEFORE I GET STARTED I SHOULD 72 00:02:43,040 --> 00:02:44,880 ACKNOWLEDGE THE WORK I'LL 73 00:02:44,880 --> 00:02:49,600 DESCRIBE TODAY HAS BEEN LARGELY 74 00:02:49,600 --> 00:02:52,440 FUNDED BY THE NCI NETWORK, NIDCR 75 00:02:52,440 --> 00:02:55,160 FUNDED SOME WORK I'LL DESCRIBE 76 00:02:55,160 --> 00:02:56,280 TODAY, AND THE NSF THROUGH THE 77 00:02:56,280 --> 00:02:59,120 CENTER AT HARVARD. 78 00:02:59,120 --> 00:03:05,200 79 00:03:05,200 --> 00:03:15,240 80 00:03:16,040 --> 00:03:19,280 TO START WITH THERE'S PEOPLE 81 00:03:19,280 --> 00:03:21,040 THAT AREN'T ENGINEERS, SO THE 82 00:03:21,040 --> 00:03:24,000 TERM VISCOELASTICITY MAY NOT BE 83 00:03:24,000 --> 00:03:25,400 SO FAMILIAR WITH YOU. 84 00:03:25,400 --> 00:03:27,360 IT RELATED TO MECHANICAL 85 00:03:27,360 --> 00:03:28,360 PROPERTY OF MATERIALS, AND MANY 86 00:03:28,360 --> 00:03:31,000 OF US ARE FAMILIAR WITH THE IDEA 87 00:03:31,000 --> 00:03:32,520 OF STIFFNESS WHICH STIFFNESS 88 00:03:32,520 --> 00:03:35,920 RELATES TO HOW MUCH RESISTANCE 89 00:03:35,920 --> 00:03:36,560 MATERIAL PROVIDES. 90 00:03:36,560 --> 00:03:39,640 YOU CAN THINK ABOUT A RUBBER 91 00:03:39,640 --> 00:03:42,720 BAND, STIFFER OR SOFTER. 92 00:03:42,720 --> 00:03:48,840 VISCOELASTICITY RELATES TO 93 00:03:48,840 --> 00:03:59,400 SOMETHING DISTINCT, THE BEHAVIOR 94 00:04:12,560 --> 00:04:14,200 OF A MATERIAL. 95 00:04:14,200 --> 00:04:15,560 YOU CAN SEE THIS DEFORMS, AS 96 00:04:15,560 --> 00:04:18,600 SOON AS THE METAL GOES BACK UP 97 00:04:18,600 --> 00:04:19,600 AGAIN, THE MATERIAL SPRINGS BACK 98 00:04:19,600 --> 00:04:25,080 TO ITS ORIGINAL SIZE AND SHAPE. 99 00:04:25,080 --> 00:04:27,600 THAT'S SOILED-LIKE BEHAVIOR, 100 00:04:27,600 --> 00:04:30,760 PURE -- SOLID-LIKE BEE HAIR 101 00:04:30,760 --> 00:04:31,440 HEIFER. 102 00:04:31,440 --> 00:04:33,080 LIQUIDS ARE VISCOUS OR 103 00:04:33,080 --> 00:04:34,160 VISCOELASTIC, THE SAME 104 00:04:34,160 --> 00:04:34,680 EXPERIMENT. 105 00:04:34,680 --> 00:04:38,520 IN THIS CASE WITH BRAIN TUSH, 106 00:04:38,520 --> 00:04:48,960 YOU CAN -- BRAIN TISSUE. 107 00:05:04,280 --> 00:05:08,320 IT REFERS TO LIQUID-LIKE VERSUS 108 00:05:08,320 --> 00:05:10,160 SOLID-LIKE BEHAVIOR OF THE 109 00:05:10,160 --> 00:05:10,640 MATERIAL. 110 00:05:10,640 --> 00:05:13,000 MOST MATERIALS HAVE SOME 111 00:05:13,000 --> 00:05:14,680 ELEMENTS BOTH VISCOUS BEHAVIOR 112 00:05:14,680 --> 00:05:16,400 AND ELASTIC, SO I WILL 113 00:05:16,400 --> 00:05:17,720 FREQUENTLY TALK ABOUT MORE 114 00:05:17,720 --> 00:05:26,480 ELASTIC MATERIALS OR MORE 115 00:05:26,480 --> 00:05:28,240 VISCOUS MATERIALS TODAY, IF WE 116 00:05:28,240 --> 00:05:32,080 MONITOR THE FORCE OR STRESS TO 117 00:05:32,080 --> 00:05:33,280 APPLY, A MORE LIQUID-LIKE 118 00:05:33,280 --> 00:05:36,880 MATERIAL ABOUT DISSIPATE -- WIL 119 00:05:36,880 --> 00:05:38,720 DISSIPATE THE STRESS OVER TIME, 120 00:05:38,720 --> 00:05:40,840 MORE ELASTIC MATERIAL WILL NOT, 121 00:05:40,840 --> 00:05:41,760 THAT'S VISCOELASTICITY. 122 00:05:41,760 --> 00:05:44,640 THE REASON WHY WE'RE INTERESTED 123 00:05:44,640 --> 00:05:45,880 IN PHYSICAL PROPERTIES AND 124 00:05:45,880 --> 00:05:47,280 MATERIALS IN CONTEXT OF CANCER 125 00:05:47,280 --> 00:05:50,440 IS THAT AS I'M SURE ALL OF YOU 126 00:05:50,440 --> 00:05:52,560 ARE AWARE, THAT SOLID TUMORS ARE 127 00:05:52,560 --> 00:05:57,240 ASSOCIATED WITH CHANGES IN THE 128 00:05:57,240 --> 00:05:58,200 EXTRACELLULAR MATRIX, INCLUDING 129 00:05:58,200 --> 00:06:00,520 FIBROSIS, LEADS TO INCREASED 130 00:06:00,520 --> 00:06:01,720 CROSS-LINKING OF THE 131 00:06:01,720 --> 00:06:02,440 EXTRACELLULAR MATRIX AND 132 00:06:02,440 --> 00:06:04,440 INCREASED DEPOSITION OF THE 133 00:06:04,440 --> 00:06:06,000 MATRIX, THERE ARE ALTERATIONS IN 134 00:06:06,000 --> 00:06:08,720 THE PHYSICAL PROPERTIES OF THE 135 00:06:08,720 --> 00:06:09,480 EXTRACELLULAR MATRIX SURROUNDING 136 00:06:09,480 --> 00:06:12,680 CELLS WITHIN THE TUMOR 137 00:06:12,680 --> 00:06:13,760 MICROENVIRONMENT AS CANCER 138 00:06:13,760 --> 00:06:14,600 PROGRESSES. 139 00:06:14,600 --> 00:06:16,920 CELLS IN THE MICROENVIRONMENT OF 140 00:06:16,920 --> 00:06:18,320 THE CANCER CAN ACTIVELY PROBE 141 00:06:18,320 --> 00:06:19,440 MECHANICAL PROPERTIES AND SO 142 00:06:19,440 --> 00:06:21,560 WHAT THIS VIDEO IS SHOWING YOU 143 00:06:21,560 --> 00:06:27,000 IS A REMINDER TO EVERYONE THAT 144 00:06:27,000 --> 00:06:28,680 CELL ADHESION AND ENGAGEMENT 145 00:06:28,680 --> 00:06:30,080 WITH EXTRACELLULAR MATRIX IS AN 146 00:06:30,080 --> 00:06:31,200 ACTIVE EVENT, NOT PASSIVE. 147 00:06:31,200 --> 00:06:34,640 THE IMMUNE CELL IS MIGRATING 148 00:06:34,640 --> 00:06:36,240 THROUGH THE COLLAGEN MATRIX, 149 00:06:36,240 --> 00:06:38,080 ACTIVELY PUSHING AND PULLING AND 150 00:06:38,080 --> 00:06:42,120 YOU CAN SEE THE INDIVIDUAL 151 00:06:42,120 --> 00:06:43,120 COLLAGEN FIBRILS BEING FORMED BY 152 00:06:43,120 --> 00:06:43,760 THE CELL. 153 00:06:43,760 --> 00:06:47,080 CELLS CAN SENSE HOW MUCH 154 00:06:47,080 --> 00:06:47,640 RESISTANCE THE EXTRACELLULAR 155 00:06:47,640 --> 00:06:50,760 MATRIX PROVIDES TO THEIR OWN 156 00:06:50,760 --> 00:06:52,640 FORCES, THIS CAN FEEDBACK AND 157 00:06:52,640 --> 00:06:53,640 ALTER CELL BEHAVIOR. 158 00:06:53,640 --> 00:06:56,560 THE IMPORTANCE OF THIS STIFFNESS 159 00:06:56,560 --> 00:06:57,640 OF THE EXTRACELLULAR MATRIX AND 160 00:06:57,640 --> 00:07:01,640 CHANGES IN STIFFNESS IN THE 161 00:07:01,640 --> 00:07:02,720 CONTEXT OF CANCER HAS BEEN 162 00:07:02,720 --> 00:07:03,920 APPRECIATED, THIS IS A COUPLE 163 00:07:03,920 --> 00:07:05,800 CLASSIC PAPERS FROM THE FIELD, 164 00:07:05,800 --> 00:07:08,080 FROM ABOUT 15, 20 YEARS AGO, 165 00:07:08,080 --> 00:07:10,680 DEMONSTRATING IN THE CONTEXT OF 166 00:07:10,680 --> 00:07:12,800 BREAST CANCER CELLS, THAT THEY 167 00:07:12,800 --> 00:07:14,880 RESPOND QUITE SIGNIFICANTLY TO 168 00:07:14,880 --> 00:07:15,960 ALTERATIONS IN STIFFNESS. 169 00:07:15,960 --> 00:07:17,400 SO THAT'S SOMETHING THAT'S BEEN 170 00:07:17,400 --> 00:07:20,680 KNOWN FOR SOME PERIOD OF TIME. 171 00:07:20,680 --> 00:07:22,440 HOWEVER, THE FOCUS IN THIS 172 00:07:22,440 --> 00:07:27,160 GENERAL SPACE AND MORE BROADLY 173 00:07:27,160 --> 00:07:28,240 MECHANOTRANSDUCTION OUTSIDE 174 00:07:28,240 --> 00:07:30,080 CANCER HAS BEEN FOCUSED ON THE 175 00:07:30,080 --> 00:07:32,160 QUESTION OF STIFFNESS. 176 00:07:32,160 --> 00:07:33,920 IN ESSENCE ACTING LIKE THE 177 00:07:33,920 --> 00:07:37,800 TISSUES IN OUR BODY AND 178 00:07:37,800 --> 00:07:38,560 EXTRACELLULAR MATRICES ARE 179 00:07:38,560 --> 00:07:41,480 ELASTIC AND CAN BE CHARACTERIZED 180 00:07:41,480 --> 00:07:42,440 BY STIFFNESS MEASURE. 181 00:07:42,440 --> 00:07:44,880 I ALREADY MENTIONED TISSUES IN 182 00:07:44,880 --> 00:07:48,400 OUR BODY, EXTRACELLULAR MATRIX 183 00:07:48,400 --> 00:07:50,360 MOLECULES ARE ACTUALLY 184 00:07:50,360 --> 00:07:51,120 VISCOELASTIC INSTEAD. 185 00:07:51,120 --> 00:07:54,200 ON THIS GRAPH WHAT WE'RE LOOKING 186 00:07:54,200 --> 00:07:56,480 AT IS THE Y-AXIS IS INDICATION 187 00:07:56,480 --> 00:08:00,840 OF THE FLUID-LIKE PROPERTIES, 188 00:08:00,840 --> 00:08:04,000 THE LOSS MODULUS, AND X-AXIS 189 00:08:04,000 --> 00:08:05,080 STORAGE MODULUS, INDICATION OF 190 00:08:05,080 --> 00:08:06,000 SOLID-LIKE PROPERTIES. 191 00:08:06,000 --> 00:08:10,400 ALL THE SKELETAL AND SOFT 192 00:08:10,400 --> 00:08:12,120 TISSUES, EVEN RECONSTITUTE 193 00:08:12,120 --> 00:08:15,960 EXTRACELLULAR MATRICES HAVE 194 00:08:15,960 --> 00:08:17,720 PROPERTIES INTERMEDIATE, BETWEEN 195 00:08:17,720 --> 00:08:21,240 A SOLID AND FLUID, SO THEY ARE 196 00:08:21,240 --> 00:08:22,200 ALL VISCOELASTIC. 197 00:08:22,200 --> 00:08:27,360 SO OF COURSE THIS RAISES THE 198 00:08:27,360 --> 00:08:28,760 QUESTION, IF CELLS ARE 199 00:08:28,760 --> 00:08:32,040 SURROUNDED BY VISCOELASTIC 200 00:08:32,040 --> 00:08:33,560 SUBSTRATES AND THE 201 00:08:33,560 --> 00:08:34,800 VISCOELASTICITY MAY CHANGE, DO 202 00:08:34,800 --> 00:08:36,200 CELLS RESPOND SIMILARLY OR 203 00:08:36,200 --> 00:08:37,760 DIFFERENTLY, IS THIS A CONTROL 204 00:08:37,760 --> 00:08:39,040 FEATURE SIMILAR TO HOW CELLS 205 00:08:39,040 --> 00:08:39,840 RESPOND TO STIFFNESS. 206 00:08:39,840 --> 00:08:42,120 NOW AS I MENTIONED A MOMENT AGO, 207 00:08:42,120 --> 00:08:45,760 ONE WAY ONE CAN QUANTIFY HOW 208 00:08:45,760 --> 00:08:48,160 VISCOELASTIC A MATERIAL IS BY 209 00:08:48,160 --> 00:08:49,360 SOMETHING CALLED STRESS 210 00:08:49,360 --> 00:08:53,760 RELAXATION TEST WHERE WE APPLY A 211 00:08:53,760 --> 00:08:54,840 GIVEN DEFORMATION, MONITOR HOW 212 00:08:54,840 --> 00:08:56,800 MUCH STRESS OR FORCE WE HAVE TO 213 00:08:56,800 --> 00:09:00,200 CONTINUE TO APPLY TO MAINTAIN 214 00:09:00,200 --> 00:09:00,720 DEFORMATION. 215 00:09:00,720 --> 00:09:04,920 A PURELY ELASTIC SOLID, THE LINE 216 00:09:04,920 --> 00:09:08,400 WOULD GO STRAIGHT ACROSS, BUT 217 00:09:08,400 --> 00:09:14,000 VARIOUS TISSUES LINE DROPS 218 00:09:14,000 --> 00:09:15,120 INDICATING VISCOELASTIC, THE 219 00:09:15,120 --> 00:09:24,480 MORE RAPIDLY THE MORE VISCOUS 220 00:09:24,480 --> 00:09:25,480 THE MATERIAL. 221 00:09:25,480 --> 00:09:27,960 NOW, THERE IS INDICATIONS THAT 222 00:09:27,960 --> 00:09:31,280 NOT ONLY THE STIFFNESS BUT 223 00:09:31,280 --> 00:09:32,400 VISCOELASTICITY OF SOLID TUMORS 224 00:09:32,400 --> 00:09:33,600 IS DIFFERENT FROM SURROUNDING 225 00:09:33,600 --> 00:09:33,840 TISSUE. 226 00:09:33,840 --> 00:09:35,560 IN THE CONTEXT OF BREAST CANCER 227 00:09:35,560 --> 00:09:41,680 AND GLIOBLASTOMA THE 228 00:09:41,680 --> 00:09:43,120 VISCOELASTICITY OF THE MATRIX 229 00:09:43,120 --> 00:09:44,080 CHANGES WITH TUMOR DEVELOPMENT, 230 00:09:44,080 --> 00:09:45,520 MAKES SENSE BECAUSE YOU'RE 231 00:09:45,520 --> 00:09:46,720 GETTING MORE CROSS-LINKING WHICH 232 00:09:46,720 --> 00:09:49,320 WILL MAKE THE TISSUE MORE 233 00:09:49,320 --> 00:09:49,600 SOLID-LIKE. 234 00:09:49,600 --> 00:09:54,440 SO WE WANTED TO BEGIN TO EXPLORE 235 00:09:54,440 --> 00:09:57,440 THE IMPACT OF VISCOELASTICITY, 236 00:09:57,440 --> 00:10:03,320 I'LL DESCRIBE HOW WE EXAMINED IN 237 00:10:03,320 --> 00:10:05,960 CONTEXT OF IMMUNE CELLS, BUT WE 238 00:10:05,960 --> 00:10:07,080 NEEDED AN EXPERIMENTAL SYSTEM TO 239 00:10:07,080 --> 00:10:07,440 EXPLORE. 240 00:10:07,440 --> 00:10:12,640 IT'S HASHED TO -- HARD TO DO IE 241 00:10:12,640 --> 00:10:15,160 BODY BECAUSE IT'S GOING TO ALTER 242 00:10:15,160 --> 00:10:16,160 MANY FEATURES SIMULTANEOUSLY. 243 00:10:16,160 --> 00:10:18,760 SO WE INSTEAD HAVE REALLY RELIED 244 00:10:18,760 --> 00:10:21,960 ON USING CELL CULTURE MODELS, 3D 245 00:10:21,960 --> 00:10:23,960 CELL CULTURE MODELS INSTEAD, 246 00:10:23,960 --> 00:10:25,720 USING MATERIALS WITH HIGHLY 247 00:10:25,720 --> 00:10:26,760 DEFINED PHYSICAL PROPERTIES. 248 00:10:26,760 --> 00:10:28,720 AND A LOT OF THE DATA THAT I'LL 249 00:10:28,720 --> 00:10:30,160 DESCRIBE FOR YOU TODAY HAS BEEN 250 00:10:30,160 --> 00:10:32,240 GENERATED WITH A PARTICULAR 251 00:10:32,240 --> 00:10:34,080 MODEL SYSTEM WHICH IS HYDRAGELS 252 00:10:34,080 --> 00:10:40,360 THAT WE CREATE FROM A 253 00:10:40,360 --> 00:10:41,240 POLYSACCHARIDE ALGINATE, 254 00:10:41,240 --> 00:10:43,760 NATURALLY DERIVED, TWO SUGAR 255 00:10:43,760 --> 00:10:46,080 UNITS, G SUGAR UNITS ON THE 256 00:10:46,080 --> 00:10:49,440 LEFT, M SUGAR UNITS ON THE 257 00:10:49,440 --> 00:10:49,640 RIGHT. 258 00:10:49,640 --> 00:10:53,400 AND ALGINATE CAN FORM A 259 00:10:53,400 --> 00:10:57,800 SPACE-FILLING ALHYDROGEL BY G 260 00:10:57,800 --> 00:11:05,640 SUGARS AND POLYMER CHAINS BELOW 261 00:11:05,640 --> 00:11:07,280 COMBINING SUCH AS CALCIUM. 262 00:11:07,280 --> 00:11:09,280 ONLY G BLOCKS WITH PARTICIPATE 263 00:11:09,280 --> 00:11:10,680 IN THE CROSS-LINKING, NOT THE M 264 00:11:10,680 --> 00:11:11,680 BLOCKS. 265 00:11:11,680 --> 00:11:14,120 WE HAVE G SUGARS IN BLOCKS, MANY 266 00:11:14,120 --> 00:11:16,920 IN A ROW, TYPICALLY ABOUT 20 IN 267 00:11:16,920 --> 00:11:17,800 A ROW. 268 00:11:17,800 --> 00:11:22,960 SO WITH THE SYSTEM WE CAN CREATE 269 00:11:22,960 --> 00:11:25,760 GELS VARY THE STIFFNESS BY 270 00:11:25,760 --> 00:11:26,360 VARYING THE CROSS-LINKER 271 00:11:26,360 --> 00:11:28,840 CONCENTRATION, AND THEN AS WE 272 00:11:28,840 --> 00:11:36,000 USE DIFFERENT MOLECULAR WEIGHT 273 00:11:36,000 --> 00:11:37,080 POLYMERS CAN CONTROL STIFFNESS. 274 00:11:37,080 --> 00:11:40,360 THE REASON WHY WE SPECIFICALLY 275 00:11:40,360 --> 00:11:41,200 USE THESE ALGINATE 276 00:11:41,200 --> 00:11:42,320 POLYSACCHARIDE GELS IS BECAUSE 277 00:11:42,320 --> 00:11:44,880 THEY ALLOW US TO INDEPENDENTLY 278 00:11:44,880 --> 00:11:49,360 CONTROL THE STIFFNESS OF THE 279 00:11:49,360 --> 00:11:52,760 GEL, VISCOELASTICITY, THE MESH 280 00:11:52,760 --> 00:11:53,760 SIDE AND PRESENTATION OF CELL 281 00:11:53,760 --> 00:11:58,200 ADHESION LIGANDS. 282 00:11:58,200 --> 00:12:01,400 THINKING ABOUT THE TYPICAL GEL 283 00:12:01,400 --> 00:12:05,160 USED IN BIOLOGY, COLLAGEN GELS, 284 00:12:05,160 --> 00:12:08,640 FIBRIN GELS, ONE CAN CHANGE THE 285 00:12:08,640 --> 00:12:10,240 STIFFNESS BY INCREASING 286 00:12:10,240 --> 00:12:11,840 CONCENTRATION OF POLYMER IN THE 287 00:12:11,840 --> 00:12:12,040 GEL. 288 00:12:12,040 --> 00:12:13,320 SO THIS DOES INCREASE STIFFNESS 289 00:12:13,320 --> 00:12:16,080 BUT AT THE SAME TIME IT CHANGES 290 00:12:16,080 --> 00:12:19,360 THE AVAILABILITY AND NUMBER OF 291 00:12:19,360 --> 00:12:20,880 CELL ADHESION LIGANDS, SHOWN 292 00:12:20,880 --> 00:12:23,400 HERE, CHANGES THE SIZE OF THE 293 00:12:23,400 --> 00:12:25,120 SPACINGS BETWEEN THE POLYMER 294 00:12:25,120 --> 00:12:28,640 CHAINS, WHICH CAN ALTER THE 295 00:12:28,640 --> 00:12:37,400 DIFFUSION OF MACROMOLECULES LIKE 296 00:12:37,400 --> 00:12:40,240 MORPHOGENS OR GROWTH FACTORS. 297 00:12:40,240 --> 00:12:44,400 WE CAN MOVE TO SYNTHETIC 298 00:12:44,400 --> 00:12:45,280 POLYMERS THAT DON'T HAVE CELLED 299 00:12:45,280 --> 00:12:49,000 A LEASER -- ADHESION PROPERTIES. 300 00:12:49,000 --> 00:12:53,080 WE CAN CONTROL THE STIFFNESS, 301 00:12:53,080 --> 00:12:55,920 AND DECOUPLE CELL ADHESION LIKE 302 00:12:55,920 --> 00:12:59,960 AND DENSITY BY CONJUGATING SMALL 303 00:12:59,960 --> 00:13:00,760 PEPTIDES LIKE RGD-CONTAINING 304 00:13:00,760 --> 00:13:03,800 PEPTIDES BUT ALTER THE MESH 305 00:13:03,800 --> 00:13:05,360 SIZE, CHANGING DIFFUSIONAL 306 00:13:05,360 --> 00:13:06,440 TRANSPORT OF MACROMOLECULES. 307 00:13:06,440 --> 00:13:07,840 THE INTERESTING THING ABOUT 308 00:13:07,840 --> 00:13:10,040 ALGINATE BECAUSE OF THIS BLOCK 309 00:13:10,040 --> 00:13:11,160 STRUCTURE I MENTIONED BEFORE, 310 00:13:11,160 --> 00:13:14,080 WE'RE ONLY THE G SUGAR -- WHERE 311 00:13:14,080 --> 00:13:16,280 ONLY THE G SUGAR BLOCKS 312 00:13:16,280 --> 00:13:17,600 PARTICIPATE IN CROSS-LINKING, IF 313 00:13:17,600 --> 00:13:20,320 YOU ADD CROSS-LINKING AGENT TO 314 00:13:20,320 --> 00:13:22,280 POLYMERS YOU'LL GET SOME 315 00:13:22,280 --> 00:13:23,400 CROSS-LINKING INDICATED BY 316 00:13:23,400 --> 00:13:25,880 ORANGE DOTS BUT THE WHOLE 317 00:13:25,880 --> 00:13:36,120 JUNCTIONAL ZONE WILL GET ALIGNED 318 00:13:36,120 --> 00:13:37,960 WITHIN THE ALHYDROGEL, WE CAN 319 00:13:37,960 --> 00:13:41,040 VARY STIFFNESS WITHOUT CHANGING 320 00:13:41,040 --> 00:13:42,800 NANOSCALE ARCHITECTURE, THE MESH 321 00:13:42,800 --> 00:13:43,680 SIZE STAYS CONSTANT. 322 00:13:43,680 --> 00:13:45,760 WE BY CONTROLLING THE MOLECULAR 323 00:13:45,760 --> 00:13:48,640 WEIGHT OF THE POLYMER CHAINS 324 00:13:48,640 --> 00:13:52,320 CONTROL HOW ENTANGLED THEY ARE 325 00:13:52,320 --> 00:13:59,760 AND CAN ALTER VISCOELASTICITY 326 00:13:59,760 --> 00:14:03,600 WHETHER THEY FLOW READILY. 327 00:14:03,600 --> 00:14:09,600 THE EARLY WORK WAS DONE BY GU, 328 00:14:09,600 --> 00:14:15,200 NOW AT HOPKINS, AND CHADHURI, 329 00:14:15,200 --> 00:14:23,040 NOW AT STANFORD, CELLS CAN BE 330 00:14:23,040 --> 00:14:23,600 INTACT IMPACTED BY 331 00:14:23,600 --> 00:14:24,040 VISCOELASTICITY. 332 00:14:24,040 --> 00:14:25,880 PUT ON A SUBSTRATE YOU CAN 333 00:14:25,880 --> 00:14:26,800 APPRECIATE THE CELLS EXHIBIT 334 00:14:26,800 --> 00:14:31,120 QUITE A BIT MORE SPREADING AND 335 00:14:31,120 --> 00:14:32,880 FOCAL ADHESION FORMATION ON THE 336 00:14:32,880 --> 00:14:42,200 VISCOELASTIC GEL AS CONTRASTED 337 00:14:42,200 --> 00:14:45,280 TO PURELY ELASTIC HERE. 338 00:14:45,280 --> 00:14:46,720 LOOKING AT ALKALINE PHOSPHATASE, 339 00:14:46,720 --> 00:14:50,320 WE VARY RATE OF STRESS 340 00:14:50,320 --> 00:14:51,960 RELAXATION BASICALLY GET GREATER 341 00:14:51,960 --> 00:14:53,480 OSTEOGENESIS OF THESE CELLS. 342 00:14:53,480 --> 00:14:54,880 WE PUBLISHED THIS WORK SEVERAL 343 00:14:54,880 --> 00:14:55,880 YEARS AGO. 344 00:14:55,880 --> 00:14:57,520 AND WHAT WE'VE BEEN MORE 345 00:14:57,520 --> 00:14:59,040 RECENTLY INTERESTED IN, THIS IS 346 00:14:59,040 --> 00:15:02,280 ALBERTO, NOW RUNNING HIS OWN 347 00:15:02,280 --> 00:15:03,520 LABORATORY AT THE CRICK 348 00:15:03,520 --> 00:15:06,000 INSTITUTE IN LONDON, INTERESTED 349 00:15:06,000 --> 00:15:11,520 IN HOW VISCOELASTICITY MIGHT 350 00:15:11,520 --> 00:15:14,600 ALTER COLLECTIVE CELL BEHAVIOR, 351 00:15:14,600 --> 00:15:16,560 USING BREAST CELLS THAT YOU MAY 352 00:15:16,560 --> 00:15:18,960 BE FAMILIAR WITH. 353 00:15:18,960 --> 00:15:20,120 HE MADE AGGREGATES, EMBEDDED 354 00:15:20,120 --> 00:15:23,360 INTO THE GELS ON THE LEFT, THAT 355 00:15:23,360 --> 00:15:25,720 WERE MORE PURELY ELASTIC, ON THE 356 00:15:25,720 --> 00:15:28,040 RIGHT MORE VISCOELASTIC, WHAT 357 00:15:28,040 --> 00:15:29,600 YOU CAN APPRECIATE IS THE 358 00:15:29,600 --> 00:15:31,120 EXPANSION OF THESE AGGREGATES IN 359 00:15:31,120 --> 00:15:33,040 ESSENCE TISSUE DEVELOPMENT HERE 360 00:15:33,040 --> 00:15:34,440 IS DRAMATICALLY DIFFERENT. 361 00:15:34,440 --> 00:15:38,040 WE GET A SLOW GROWTH ON THE LEFT 362 00:15:38,040 --> 00:15:40,080 AND MORE PURELY ELASTIC 363 00:15:40,080 --> 00:15:42,520 MATERIAL, THE TISSUE MAINTAINS 364 00:15:42,520 --> 00:15:43,840 SYMMETRY, WHILE ON THE RIGHT WE 365 00:15:43,840 --> 00:15:47,360 ACTUALLY HAVE MUCH MORE RAPID 366 00:15:47,360 --> 00:15:47,960 GROWTH. 367 00:15:47,960 --> 00:15:50,960 WE HAVE BRANCH FORMATION, WE 368 00:15:50,960 --> 00:15:52,360 BREAK SYMMETRY, SO DRAMATICALLY 369 00:15:52,360 --> 00:15:53,360 DIFFERENT CELLULAR BEHAVIOR JUST 370 00:15:53,360 --> 00:15:56,520 BECAUSE ON THE RIGHT IT'S MORE 371 00:15:56,520 --> 00:15:59,040 VISCOELASTIC, ON LEFT MORE 372 00:15:59,040 --> 00:15:59,960 ELASTIC. 373 00:15:59,960 --> 00:16:04,200 SO WE GET MORPHOLOGICALLY STABLE 374 00:16:04,200 --> 00:16:07,760 TISSUE GROWTH OR MORPHOLOGICALLY 375 00:16:07,760 --> 00:16:14,040 UNSTABLE TISSUE GROWTH. 376 00:16:14,040 --> 00:16:15,920 WE CONJUGATE SMALL RPG PEPTIDES 377 00:16:15,920 --> 00:16:17,320 AND MATCHED STORED MODULUS, THE 378 00:16:17,320 --> 00:16:19,320 STIFFNESS, BUT WE VARY THE RATE 379 00:16:19,320 --> 00:16:20,880 OF STRESS RELAXATION BY CHANGING 380 00:16:20,880 --> 00:16:23,200 THE MOLECULAR WEIGHT OF THE 381 00:16:23,200 --> 00:16:24,400 POLYMER. 382 00:16:24,400 --> 00:16:26,320 IF WE LOOK AT THE 383 00:16:26,320 --> 00:16:27,960 CROSS-SECTIONS, YOU CAN 384 00:16:27,960 --> 00:16:28,960 APPRECIATE HOW DRAMATICALLY 385 00:16:28,960 --> 00:16:31,000 DIFFERENT GROWTH OF THESE 386 00:16:31,000 --> 00:16:34,120 ORGANOIDS IS AS WE VARY THE -- 387 00:16:34,120 --> 00:16:36,080 PUT THEM IN ELASTIC OR 388 00:16:36,080 --> 00:16:37,840 VISCOELASTIC SUBSTRATE, YOU CAN 389 00:16:37,840 --> 00:16:41,320 APPRECIATE DRAMATIC DIFFERENCE 390 00:16:41,320 --> 00:16:42,440 HERE. 391 00:16:42,440 --> 00:16:43,720 NOW, THIS CHANGE IN 392 00:16:43,720 --> 00:16:47,120 VISCOELASTICITY DRIVES AN 393 00:16:47,120 --> 00:16:47,720 EPITHELIAL TO MESENCHYMAL 394 00:16:47,720 --> 00:16:49,760 TRANSITION, EMT, OF THE CELLS. 395 00:16:49,760 --> 00:16:59,600 IF WE LOOK AT THE VIMENTIN 396 00:16:59,600 --> 00:17:04,400 EXPRESSION, THE BRANCHES ARE 397 00:17:04,400 --> 00:17:10,120 PENETRATING INTO THE SURROUNDING 398 00:17:10,120 --> 00:17:10,800 VISCOELASTIC GEL. 399 00:17:10,800 --> 00:17:21,320 CELLS IN THE ELASTIC SUBSTRATE 400 00:17:23,320 --> 00:17:24,480 EXPRESS CYTOKERATIN FORMATION. 401 00:17:24,480 --> 00:17:31,920 WE SEE EXPRESSION OF SNAIL, 402 00:17:31,920 --> 00:17:33,640 SLUG, ZEB1 CELLS, THIS IS AN 403 00:17:33,640 --> 00:17:35,600 EFFECT IN TERMS OF IMPACT ON 404 00:17:35,600 --> 00:17:37,280 TISSUE GROWTH, NOT JUST SEEN IN 405 00:17:37,280 --> 00:17:39,240 VITRO, BUT WE ALSO SEE THIS IN 406 00:17:39,240 --> 00:17:39,640 VIVO. 407 00:17:39,640 --> 00:17:42,440 IF WE TAKE THE CELLS, WE 408 00:17:42,440 --> 00:17:44,680 TRANSPLANT THEM INTO GELS MORE 409 00:17:44,680 --> 00:17:47,440 VISCOELASTIC, ELASTIC, SEE MUCH 410 00:17:47,440 --> 00:17:48,520 MORE DRAMATIC GROWTH, AND 411 00:17:48,520 --> 00:17:50,480 BASICALLY INVASION INTO THE 412 00:17:50,480 --> 00:17:53,680 SURROUNDING TISSUE IN THE 413 00:17:53,680 --> 00:17:54,160 VISCOELASTIC SUBSTRATE. 414 00:17:54,160 --> 00:17:58,280 NOW, WE'VE BEEN INTERESTED IN 415 00:17:58,280 --> 00:17:59,480 TRYING TO MATHEMATICALLY MODEL 416 00:17:59,480 --> 00:18:01,160 THIS BEHAVIOR TO GET A BETTER 417 00:18:01,160 --> 00:18:02,640 UNDERSTANDING, ALSO TO ENABLE US 418 00:18:02,640 --> 00:18:04,840 TO QUICKLY DO A WIDE VARIETY OF 419 00:18:04,840 --> 00:18:06,360 DIFFERENT EXPERIMENTS BECAUSE WE 420 00:18:06,360 --> 00:18:09,920 HAVE A BIG VARIABLE SPACE HERE. 421 00:18:09,920 --> 00:18:12,840 SO IN COLLABORATION WITH 422 00:18:12,840 --> 00:18:15,720 MAHADEVAN AT HARVARD WE'RE 423 00:18:15,720 --> 00:18:17,680 MODELING THE MATRIX USING 424 00:18:17,680 --> 00:18:19,240 CLASSIC VISCOELASTIC AND ELASTIC 425 00:18:19,240 --> 00:18:20,120 APPROACHES, CONSIDERING THE 426 00:18:20,120 --> 00:18:21,440 MATRIX TO BE PASSIVE, AND FOR 427 00:18:21,440 --> 00:18:23,880 THE TISSUE WE MODEL IT AS 428 00:18:23,880 --> 00:18:25,480 BASICALLY BEING A COLLECTION OF 429 00:18:25,480 --> 00:18:27,240 INDIVIDUAL CELLS, EACH OF THESE 430 00:18:27,240 --> 00:18:30,200 CELLS HAS THE CAPACITY TO EITHER 431 00:18:30,200 --> 00:18:30,880 PROLIFERATE OR MIGRATE. 432 00:18:30,880 --> 00:18:32,600 THOSE ARE THE ONLY TWO BEHAVIORS 433 00:18:32,600 --> 00:18:33,720 CELLS WITH EXHIBIT. 434 00:18:33,720 --> 00:18:37,560 WHAT YOU CAN APPRECIATE IS THAT 435 00:18:37,560 --> 00:18:38,960 THESE SIMULATIONS REPLICATE THE 436 00:18:38,960 --> 00:18:46,040 BEAVER -- BEHAVIOR, INNOVATING 437 00:18:46,040 --> 00:18:48,680 AND GROWING MORE RAPIDLY. 438 00:18:48,680 --> 00:18:52,640 THIS IS QUANTIFICATION OVER 439 00:18:52,640 --> 00:18:53,360 MULTIPLE SIMULATIONS, PART OF 440 00:18:53,360 --> 00:18:55,280 THE REASON WE WANT TO UNDERSTAND 441 00:18:55,280 --> 00:18:57,920 FROM THIS PERSPECTIVE IS GAIN 442 00:18:57,920 --> 00:18:58,960 INSIGHT INTO WHAT'S CONTROLLING 443 00:18:58,960 --> 00:19:00,440 THIS PROCESS THAT WE'RE 444 00:19:00,440 --> 00:19:02,960 EXAMINING, ALSO TO MORE RAPIDLY 445 00:19:02,960 --> 00:19:05,560 EXPLORE THE EXPERIMENTAL SPACE. 446 00:19:05,560 --> 00:19:09,280 SO, FOR EXAMPLE, HERE WITH THIS 447 00:19:09,280 --> 00:19:10,080 3D CONSTRUCTION, IT RECOMMENDS 448 00:19:10,080 --> 00:19:13,880 EACH ONE OF THESE DOTS IS A 449 00:19:13,880 --> 00:19:15,960 SIMULATION WHERE WE VARIED 450 00:19:15,960 --> 00:19:17,040 PARAMETERS IN OUR EXPERIMENTAL 451 00:19:17,040 --> 00:19:18,720 SYSTEM, AND THEN RUN A 452 00:19:18,720 --> 00:19:19,360 MATHEMATICAL SIMULATION. 453 00:19:19,360 --> 00:19:21,560 SO WE CAN VERY RAPIDLY DO, YOU 454 00:19:21,560 --> 00:19:22,440 KNOW, HUNDREDS OF SIMULATIONS 455 00:19:22,440 --> 00:19:24,480 WHILE DOING HUNDREDS OF 456 00:19:24,480 --> 00:19:26,840 EXPERIMENTS WOULD TAKE US YEARS. 457 00:19:26,840 --> 00:19:28,680 AN INTERESTING OUTCOME OF THIS 458 00:19:28,680 --> 00:19:30,520 IS WE'RE ABLE TO IDENTIFY 459 00:19:30,520 --> 00:19:31,720 REGIONS IN THIS VARIABLE SPACE 460 00:19:31,720 --> 00:19:33,040 THAT LEAD TO THIS UNSTABLE 461 00:19:33,040 --> 00:19:36,040 GROWTH, THESE ARE ALL THE RED 462 00:19:36,040 --> 00:19:37,440 DOTS, AND THEN CONVERSELY A 463 00:19:37,440 --> 00:19:41,160 SPACE WHERE WE ACTUALLY GET THE 464 00:19:41,160 --> 00:19:42,040 STABLE GROWTH, BASICALLY 465 00:19:42,040 --> 00:19:43,280 ENCOMPASSED IN GREEN REGION IN 466 00:19:43,280 --> 00:19:45,440 THE THREE DIMENSIONAL SPACE. 467 00:19:45,440 --> 00:19:46,320 WE FOUND BASICALLY THIS 468 00:19:46,320 --> 00:19:48,600 TRANSITION BETWEEN STABLE AND 469 00:19:48,600 --> 00:19:51,560 UNSTABLE GROWTH IS REGULATED BY 470 00:19:51,560 --> 00:19:52,600 THREE DIMENSIONAL PARAMETERS, 471 00:19:52,600 --> 00:19:57,120 FIRST IS A, WHICH IS THE RATIO 472 00:19:57,120 --> 00:20:05,920 OF BASICALLY DEPENDENT DEPENDEF 473 00:20:05,920 --> 00:20:07,440 MOTILITY, THE SECOND IS BETWEEN 474 00:20:07,440 --> 00:20:17,320 THE TISSUE AND MATRIX VISCOSITY. 475 00:20:17,320 --> 00:20:20,760 WE THINK THIS COULD BE BROADLY 476 00:20:20,760 --> 00:20:22,360 USEFUL TO EXPLORE MORPHOGENESIS 477 00:20:22,360 --> 00:20:24,440 AND TUMORIGENESIS IN A NUMBER OF 478 00:20:24,440 --> 00:20:25,560 CONTEXTS. 479 00:20:25,560 --> 00:20:28,040 WE'VE ALSO BEEN INTERESTED IN 480 00:20:28,040 --> 00:20:30,800 DETERMINING WHETHER THIS IDEA OF 481 00:20:30,800 --> 00:20:32,080 VISCOELASTICITY CONTROLLING 482 00:20:32,080 --> 00:20:34,640 ORGANOGENESIS IS BROADLY 483 00:20:34,640 --> 00:20:36,120 RELEVANT OR SPECIFIC TO CELL 484 00:20:36,120 --> 00:20:38,640 SYSTEM I DESCRIBED. 485 00:20:38,640 --> 00:20:45,520 WE CAN TAKE THIS AND CREATE 486 00:20:45,520 --> 00:20:47,560 INTERPENETRATING NETWORKS, FOR 487 00:20:47,560 --> 00:20:49,800 EXAMPLE MATRIGEL TO DECOUPLE 488 00:20:49,800 --> 00:20:50,720 FROM OTHER FEATURE, HERE 489 00:20:50,720 --> 00:20:52,920 CONTROLLING PHYSICAL PROPERTIES 490 00:20:52,920 --> 00:20:54,880 TO KEEP THE MATRIGEL CONSTANT. 491 00:20:54,880 --> 00:20:56,280 AND WE CAN SEE FOR EXAMPLE THAT 492 00:20:56,280 --> 00:21:06,760 IF WE DO THIS WITH IPNs CAN 493 00:21:07,080 --> 00:21:07,640 KEEP TRANSPORTERS CONSTANT, 494 00:21:07,640 --> 00:21:10,080 INCREASING CONCENTRATION TO MAKE 495 00:21:10,080 --> 00:21:11,280 IT STIFFER, SIMULTANEOUSLY 496 00:21:11,280 --> 00:21:12,840 DIMINISHING DIFFUSION. 497 00:21:12,840 --> 00:21:15,320 WITH THESE KINDS OF NETWORKS CAN 498 00:21:15,320 --> 00:21:16,320 EXAMINE OTHER SYSTEMS. 499 00:21:16,320 --> 00:21:21,480 FOR EXAMPLE, WE'VE LOOKED AT 500 00:21:21,480 --> 00:21:23,320 INTESTINAL ORGANOID DEVELOPMENT. 501 00:21:23,320 --> 00:21:33,800 IN THE ELASTIC EXTRACELLULAR 502 00:21:38,600 --> 00:21:41,480 MATRICES IS SLOW. 503 00:21:41,480 --> 00:21:43,880 ON THE VISCOELASTIC MATRICES WE 504 00:21:43,880 --> 00:21:45,080 GET DIFFERENTIATION OF STEM 505 00:21:45,080 --> 00:21:47,080 CELLS INTO DAUGHTER CELLS ONE 506 00:21:47,080 --> 00:21:48,720 WOULD EXPECT TO SEE, INTESTINAL 507 00:21:48,720 --> 00:21:50,480 TISSUE, WE SEE MAINTENANCE OF 508 00:21:50,480 --> 00:21:52,440 THE STEM CELL POPULATION 509 00:21:52,440 --> 00:21:54,840 SPECIFICALLY AT REGIONS OF HIGH 510 00:21:54,840 --> 00:21:59,360 CURVATURE AS OTHERS HAVE 511 00:21:59,360 --> 00:22:00,640 PREVIOUSLY DESCRIBED. 512 00:22:00,640 --> 00:22:04,600 SO, WE BASICALLY THINK MATRIX 513 00:22:04,600 --> 00:22:07,200 ELASTICITY IS A FEATURE OF HOW 514 00:22:07,200 --> 00:22:10,520 TUMORS MAY GROW, CONTROLS 515 00:22:10,520 --> 00:22:11,040 PROLIFERATION, INVASION, 516 00:22:11,040 --> 00:22:13,240 SYMMETRY BREAKING, 517 00:22:13,240 --> 00:22:13,680 MECHANOTRANSDUCTION. 518 00:22:13,680 --> 00:22:16,960 I WON'T GO THROUGH THE 519 00:22:16,960 --> 00:22:18,800 MECHANOTRANSDUCTION PATHWAYS BUT 520 00:22:18,800 --> 00:22:19,920 WHAT OUR STUDIES HAVE 521 00:22:19,920 --> 00:22:22,000 DEMONSTRATED IS THAT THESE 522 00:22:22,000 --> 00:22:24,920 EFFECTS ARE DEPENDENT ON ABILITY 523 00:22:24,920 --> 00:22:29,200 OF THE CELLS TO ENGAGE WITH THE 524 00:22:29,200 --> 00:22:32,720 MATERIAL, SPECIFICALLY RGD 525 00:22:32,720 --> 00:22:36,120 LIGAND IN THESE GELS VIA 526 00:22:36,120 --> 00:22:38,240 INTEGRIN RECEPTORS, WE SEE 527 00:22:38,240 --> 00:22:39,600 SIGNALING THAT REGULATES 528 00:22:39,600 --> 00:22:46,480 ASSEMBLY OF ACT ALLOWS TO PROBE 529 00:22:46,480 --> 00:22:47,200 PHYSICAL PROPERTIES, MEDIATING 530 00:22:47,200 --> 00:22:54,720 RESPONSIVENESS OF CELLS TO THE 531 00:22:54,720 --> 00:22:55,280 MATRIX VISCOELASTICITY. 532 00:22:55,280 --> 00:22:56,920 THOSE CELLS RESPOND. 533 00:22:56,920 --> 00:22:58,440 WHAT KYLE FOUND, HE MOVED TO U 534 00:22:58,440 --> 00:23:00,600 PENN TO TAKE AN ACADEMIC 535 00:23:00,600 --> 00:23:01,640 POSITION THERE, BECAME 536 00:23:01,640 --> 00:23:03,280 INTERESTED IN SOMETHING THAT 537 00:23:03,280 --> 00:23:04,920 COULD BE QUITE IMPORTANT WHICH 538 00:23:04,920 --> 00:23:07,520 IS HE BEGAN TO ASK WHETHER 539 00:23:07,520 --> 00:23:10,040 IMMUNE CELLS MIGHT ACTUALLY ALSO 540 00:23:10,040 --> 00:23:12,960 RESPOND TO THESE CHANGES IN THE 541 00:23:12,960 --> 00:23:16,720 VISCOELASTICITY OF THE 542 00:23:16,720 --> 00:23:21,280 EXTRACELLULAR MATRIX, INTERESTED 543 00:23:21,280 --> 00:23:22,960 IN CON MYELOFIBROSIS, WHICH 544 00:23:22,960 --> 00:23:24,280 INVOLVES BASICALLY MUTATIONS IN 545 00:23:24,280 --> 00:23:28,760 HEMATOPOIETIC STEM CELLS AND IS 546 00:23:28,760 --> 00:23:29,920 ASSOCIATED WITH BASICALLY 547 00:23:29,920 --> 00:23:32,480 CHANGES IN FIBROSIS WITHIN THE 548 00:23:32,480 --> 00:23:35,760 BONE MARROW, AND THEN 549 00:23:35,760 --> 00:23:37,360 ALTERATIONS IN MYELOID CELLS. 550 00:23:37,360 --> 00:23:41,320 SPECIFICALLY IN THIS DISEASE AS 551 00:23:41,320 --> 00:23:46,080 INDICATED BY THIS STAINING ONE 552 00:23:46,080 --> 00:23:48,440 GETS DEPOSITION OF EXTRACELLULAR 553 00:23:48,440 --> 00:23:49,840 MATRIX, CHANGES IN PHYSICAL 554 00:23:49,840 --> 00:23:50,200 PROPERTIES. 555 00:23:50,200 --> 00:23:52,680 WHAT KYLE PROPOSED WAS THAT THE 556 00:23:52,680 --> 00:23:53,480 VISCOELASTICITY WAS PROBABLY 557 00:23:53,480 --> 00:23:54,760 ALSO CHANGING IN THE CONTEXT OF 558 00:23:54,760 --> 00:23:57,080 THESE DISEASES AND THIS MIGHT BE 559 00:23:57,080 --> 00:23:59,600 PLAYING AN IMPORTANT ROLE IN 560 00:23:59,600 --> 00:24:00,360 MYELOID BIOLOGY. 561 00:24:00,360 --> 00:24:03,080 AND THIS WORK I'LL DESCRIBE NEXT 562 00:24:03,080 --> 00:24:06,160 HAS BEEN DONE IN COLLABORATION 563 00:24:06,160 --> 00:24:10,880 WITH THE DANA FAR BORE, AND 564 00:24:10,880 --> 00:24:11,640 CHARITE IN BERLIN. 565 00:24:11,640 --> 00:24:13,280 TO START WITH KYLE WANTED SOME 566 00:24:13,280 --> 00:24:14,920 SENSE OF WHAT KIND OF PHYSICAL 567 00:24:14,920 --> 00:24:20,200 PROPERTIES HE SHOULD MODEL IN 568 00:24:20,200 --> 00:24:23,120 HIS CELL CULTURE SYSTEM, WE 569 00:24:23,120 --> 00:24:24,320 CHARACTERIZED NORMAL BONE 570 00:24:24,320 --> 00:24:32,240 MARROW, THE NORMAL RANGE IS 1 TO 571 00:24:32,240 --> 00:24:32,760 10-KPAs. 572 00:24:32,760 --> 00:24:34,200 FRACTURE HEMATOMAS FROM 573 00:24:34,200 --> 00:24:35,600 PATIENTS, WERE ABLE TO 574 00:24:35,600 --> 00:24:37,720 CHARACTERIZE THEIR PROPERTIES 575 00:24:37,720 --> 00:24:40,960 AND THEY WERE VISCOELASTIC WITH 576 00:24:40,960 --> 00:24:42,760 HALFTIME OF RELAXATION OF 400 577 00:24:42,760 --> 00:24:42,960 SECONDS. 578 00:24:42,960 --> 00:24:46,440 THEN KYLE SET ABOUT DESIGNING A 579 00:24:46,440 --> 00:24:47,880 ALHYDROGEL SYSTEM FOR CELL 580 00:24:47,880 --> 00:24:50,760 CULTURE SYSTEM TO MIMIC 581 00:24:50,760 --> 00:24:53,520 TRANSITION FROM NORMAL PHYSICAL 582 00:24:53,520 --> 00:24:55,040 PROPERTIES TO ABNORMAL PHYSICAL 583 00:24:55,040 --> 00:24:55,440 PROPERTIES. 584 00:24:55,440 --> 00:25:03,120 HE AGAIN WENT TO USE ALGINATE, 585 00:25:03,120 --> 00:25:04,880 POLYSACCHARIDE I DESCRIBED, TO 586 00:25:04,880 --> 00:25:05,880 ACCESS LONG RELAXATION TIMES 587 00:25:05,880 --> 00:25:07,320 BASED ON WHAT WAS HAPPENING IN 588 00:25:07,320 --> 00:25:10,440 THE BONE MARROW WITH ALL THE 589 00:25:10,440 --> 00:25:10,880 FIBROSIS. 590 00:25:10,880 --> 00:25:13,840 SO, IN ADDITION TO THE ICONIC 591 00:25:13,840 --> 00:25:15,480 CROSS-LINKING I DESCRIBED 592 00:25:15,480 --> 00:25:17,760 BEFORE, HE BUILT IN SOME 593 00:25:17,760 --> 00:25:19,080 COVALENT CROSS-LINKING USING 594 00:25:19,080 --> 00:25:20,160 CLICK CHEMISTRY, THE BASIC IDEA 595 00:25:20,160 --> 00:25:22,920 HERE IS HE WOULD PUT SMALL CLICK 596 00:25:22,920 --> 00:25:24,720 FUNCTIONAL GROUPS ON THE 597 00:25:24,720 --> 00:25:27,040 ALGINATE, THESE WOULD NOT HAVE A 598 00:25:27,040 --> 00:25:29,360 LONG SPACER, THEY COULD ONLY 599 00:25:29,360 --> 00:25:33,040 REACT WITH EACH OTHER IF 600 00:25:33,040 --> 00:25:34,040 ADJACENT POLYMER CHAINS WERE 601 00:25:34,040 --> 00:25:36,280 ALREADY QUITE CLOSE. 602 00:25:36,280 --> 00:25:38,240 DO IONIC CROSS-LINKING, THAT 603 00:25:38,240 --> 00:25:40,080 BRINGS POLYMER CHANGES IN CLOSE 604 00:25:40,080 --> 00:25:40,960 PROXIMITY, THEN THE CLICK 605 00:25:40,960 --> 00:25:42,840 CHEMICAL GROUPS HERE WOULD THEN 606 00:25:42,840 --> 00:25:45,760 HAVE THE OPPORTUNITY TO REACT IN 607 00:25:45,760 --> 00:25:48,080 MORE OR LESS BASICALLY CREATING 608 00:25:48,080 --> 00:25:51,280 A MORE ELASTIC COMPONENT TO 609 00:25:51,280 --> 00:25:52,440 THESE CROSS-LINKING JUNCTIONAL 610 00:25:52,440 --> 00:25:52,640 ZONES. 611 00:25:52,640 --> 00:25:56,200 AND HE DID DEMONSTRATE HE COULD 612 00:25:56,200 --> 00:25:57,000 CREATE BASICALLY MORE 613 00:25:57,000 --> 00:25:58,240 VISCOELASTIC OR MORE ELASTIC 614 00:25:58,240 --> 00:26:00,880 MATERIALS BY COMBINING THIS 615 00:26:00,880 --> 00:26:01,840 ICONIC AND COVALENT 616 00:26:01,840 --> 00:26:02,640 CROSS-LINKING. 617 00:26:02,640 --> 00:26:06,560 A KEY FEATURE AS WELL IS CONTEXT 618 00:26:06,560 --> 00:26:07,480 OF FIBROSIS. 619 00:26:07,480 --> 00:26:09,080 OBVIOUSLY COLLAGEN TYPE 1 IS A 620 00:26:09,080 --> 00:26:10,840 KEY COMPONENT, SO WE WANTED TO 621 00:26:10,840 --> 00:26:13,880 HAVE THAT ASPECT TO THIS MODEL 622 00:26:13,880 --> 00:26:14,320 SYSTEM. 623 00:26:14,320 --> 00:26:14,960 HE MADE INTERPENETRATING 624 00:26:14,960 --> 00:26:16,920 NETWORKS AS I DESCRIBED EARLIER 625 00:26:16,920 --> 00:26:19,760 BUT THIS TIME WITH TYPE 1 626 00:26:19,760 --> 00:26:21,120 COLLAGEN, DEMONSTRATING THE TYPE 627 00:26:21,120 --> 00:26:28,880 1 COLLAGEN RED READILY ASSEMBL, 628 00:26:28,880 --> 00:26:30,320 MEDIATING CELL ENGAGEMENT AND 629 00:26:30,320 --> 00:26:32,280 THE ALGINATE HERE BASICALLY TO 630 00:26:32,280 --> 00:26:33,960 CHANGE THE PHYSICAL PROPERTIES 631 00:26:33,960 --> 00:26:42,840 OF THE GELS, INDEPENDENT MANNER. 632 00:26:42,840 --> 00:26:44,680 NOW HE TOOK MUSEUM MONOCYTES, 633 00:26:44,680 --> 00:26:47,480 ENCAPSULATED IN GELS OF VARYING 634 00:26:47,480 --> 00:26:50,320 STIFFNESS OR VARYING LEVELS OF 635 00:26:50,320 --> 00:26:57,760 VISCOELASTICITY, CHARACTERIZED 636 00:26:57,760 --> 00:27:00,520 CYTOKINE SECRETED, YOU CAN 637 00:27:00,520 --> 00:27:02,240 APPRECIATE ONE GETS SIGNIFICANT 638 00:27:02,240 --> 00:27:04,640 UPREGULATION OF SECRETION OF A 639 00:27:04,640 --> 00:27:06,320 LOT OF INFLAMMATORY CYTOKINES, 640 00:27:06,320 --> 00:27:08,160 FROM THE CELLS, WHEN THEY ARE IN 641 00:27:08,160 --> 00:27:09,760 THE MORE ELASTIC STIFF MATERIAL 642 00:27:09,760 --> 00:27:11,600 AS CONTRASTED TO ANY OF THE 643 00:27:11,600 --> 00:27:12,320 OTHER CONDITIONS. 644 00:27:12,320 --> 00:27:15,280 NOW IF WE LOOK AT THE CELLS 645 00:27:15,280 --> 00:27:17,120 THEMSELVES, LOOK AT CELL SURFACE 646 00:27:17,120 --> 00:27:19,920 MARKERS, ONE SEES, FOR EXAMPLE, 647 00:27:19,920 --> 00:27:27,320 IN THIS TOP PLOT A SIGNIFICANT 648 00:27:27,320 --> 00:27:31,360 INCREASE IN EXPRESSION IN 649 00:27:31,360 --> 00:27:35,880 ELASTIC VERSUS SUBSTRATE, 650 00:27:35,880 --> 00:27:36,840 SIGNIFICANT UPREGULATION OF 651 00:27:36,840 --> 00:27:43,560 HLA-DR, CD80, TDL 1, WE'RE 652 00:27:43,560 --> 00:27:45,520 INDUCING DIFFERENTATION, DRIVEN 653 00:27:45,520 --> 00:27:47,840 BY CHANGE IN VISCOELASTICITY. 654 00:27:47,840 --> 00:27:49,480 NOW, WE'VE DONE SOME GENE 655 00:27:49,480 --> 00:27:51,200 EXPRESSION ANALYSIS OF THESE 656 00:27:51,200 --> 00:27:53,360 CELLS, AND FOUND SIGNIFICANT 657 00:27:53,360 --> 00:27:54,440 ALTERATIONS IN GENE EXPRESSION, 658 00:27:54,440 --> 00:27:56,760 FOR THE CELLS IN THE MORE 659 00:27:56,760 --> 00:28:02,680 VISCOUS GELS HAVE A PATTERN OF 660 00:28:02,680 --> 00:28:04,360 GENE EXPRESSION REPRESENTATIVE 661 00:28:04,360 --> 00:28:07,160 OF MONOCYTES, MATURE DENDRITIC 662 00:28:07,160 --> 00:28:09,040 CELLS, MORE INFLAMMATORY PATTERN 663 00:28:09,040 --> 00:28:10,400 IN THE ELASTIC SUBSTRATES. 664 00:28:10,400 --> 00:28:13,600 NOW, THIS IS ALL IN A CELL 665 00:28:13,600 --> 00:28:15,160 CULTURE MODEL. 666 00:28:15,160 --> 00:28:17,800 IT'S DIFFICULT TO COMPARE 667 00:28:17,800 --> 00:28:19,760 DIRECTLY TO WHAT'S HAPPENING IN 668 00:28:19,760 --> 00:28:19,960 VIVO. 669 00:28:19,960 --> 00:28:23,240 BUT KYLE WAS ABLE TO ACCESS 670 00:28:23,240 --> 00:28:24,480 THROUGH SOME COLLABORATORS A 671 00:28:24,480 --> 00:28:26,320 DATASET OF CHANGES IN GENE 672 00:28:26,320 --> 00:28:31,120 EXPRESSION OF PATIENTS WITH 673 00:28:31,120 --> 00:28:31,760 PRIMARY MYELOFIBROSIS, 674 00:28:31,760 --> 00:28:32,920 TRANSITION FROM EARLY TO LATE 675 00:28:32,920 --> 00:28:35,160 STAGE DISEASE WHICH ENCOMPASSES 676 00:28:35,160 --> 00:28:36,960 CHANGES IN FIBROSIS AND CHANGING 677 00:28:36,960 --> 00:28:39,200 IN STIFFENING AND CHANGES IN 678 00:28:39,200 --> 00:28:42,320 VISCOELASTICITY, AND SO IF YOU 679 00:28:42,320 --> 00:28:43,760 LOOKED AT EXPRESSION, CHANGES IN 680 00:28:43,760 --> 00:28:45,480 EXPRESSION OF A NUMBER OF GENES, 681 00:28:45,480 --> 00:28:50,040 AS WE WENT FROM ELASTIC STIFF TO 682 00:28:50,040 --> 00:28:50,840 VISCOELASTIC MATERIAL, COMPARED 683 00:28:50,840 --> 00:28:55,320 THAT TO THE SAME GENES AS THEY 684 00:28:55,320 --> 00:28:58,920 WERE ALTERED IN EXPRESSION FROM 685 00:28:58,920 --> 00:29:00,360 EARLY TO LATE STAGE ONE SEES 686 00:29:00,360 --> 00:29:01,760 GOOD CORRELATION BETWEEN THESE. 687 00:29:01,760 --> 00:29:03,840 IT LOOKS LIKE CHANGES WE'RE 688 00:29:03,840 --> 00:29:05,720 SEEING IN MODEL SYSTEM ARE 689 00:29:05,720 --> 00:29:07,680 SIMILAR TO THE CHANGES ONE SEES 690 00:29:07,680 --> 00:29:11,840 IN PATIENTS AS THE DISEASE 691 00:29:11,840 --> 00:29:12,280 PROGRESSES. 692 00:29:12,280 --> 00:29:14,240 NOW, FIBROSIS ALSO OCCURS IN A 693 00:29:14,240 --> 00:29:16,440 VARIETY OF OTHER SETTINGS. 694 00:29:16,440 --> 00:29:19,200 SO KYLE ALSO WENT AND LOOKED AT 695 00:29:19,200 --> 00:29:20,920 SINGLE CELL RNAseq DATA THAT 696 00:29:20,920 --> 00:29:21,840 HAD PREVIOUSLY BEEN PUBLISHED, 697 00:29:21,840 --> 00:29:24,640 IN THIS CASE WITH PATIENTS WITH 698 00:29:24,640 --> 00:29:26,640 PULMONARY FIBROSIS OR PEOPLE 699 00:29:26,640 --> 00:29:28,720 WITH NORMAL LUNG TISSUE. 700 00:29:28,720 --> 00:29:31,920 AND LOOKED AT BASICALLY MONOCYTE 701 00:29:31,920 --> 00:29:34,720 EXPRESSION OF THE GENE SETS WE 702 00:29:34,720 --> 00:29:35,720 IDENTIFIED WERE REPRESENTATIVE 703 00:29:35,720 --> 00:29:37,720 OF CELLS BASICALLY IN THESE 704 00:29:37,720 --> 00:29:39,000 ELASTIC MATERIALS. 705 00:29:39,000 --> 00:29:43,720 AND WHAT ONE SEES IS ELASTIC 706 00:29:43,720 --> 00:29:45,160 GENE SIGNATURE DRAMATICALLY 707 00:29:45,160 --> 00:29:47,320 UPREGULATED IN MONOCYTES AND 708 00:29:47,320 --> 00:29:51,480 PATIENTS WITH PULMONARY FIBROSIS 709 00:29:51,480 --> 00:29:53,280 VERSUS NORMAL DONOR INDICATING 710 00:29:53,280 --> 00:29:54,320 PHYSIOLOGIC RELEVANCE IN TERMS 711 00:29:54,320 --> 00:29:57,360 OF REFLECTING WHAT WE SEE IN THE 712 00:29:57,360 --> 00:29:59,040 BODY AS WELL. 713 00:29:59,040 --> 00:30:01,440 FURTHERMORE, WHAT KYLE WAS ABLE 714 00:30:01,440 --> 00:30:03,080 TO DEMONSTRATE THAT GENE 715 00:30:03,080 --> 00:30:05,160 EXPRESSION OF MONOCYTES IN 716 00:30:05,160 --> 00:30:06,960 VISCOUS GELS ARE ACTUALLY 717 00:30:06,960 --> 00:30:09,000 ASSOCIATED WITH POOR OVERALL 718 00:30:09,000 --> 00:30:13,680 SURVIVAL FROM TCGA DATA. 719 00:30:13,680 --> 00:30:19,920 YOU CAN SEE HERE HUMAN TUMORS, 720 00:30:19,920 --> 00:30:23,080 PATIENT DATA, CUTANEOUS MELANOMA 721 00:30:23,080 --> 00:30:29,240 AND SQUAMOUS CARS CARCINOMA. 722 00:30:29,240 --> 00:30:30,800 FINDINGS ARE PATHOLOGICALLY 723 00:30:30,800 --> 00:30:31,560 RELEVANT. 724 00:30:31,560 --> 00:30:33,440 WE'D LIKE TO UNDERSTAND 725 00:30:33,440 --> 00:30:36,280 MECHANISM BY WHICH THESE CELLS 726 00:30:36,280 --> 00:30:38,120 ARE SENSING, THESE CHANGING 727 00:30:38,120 --> 00:30:39,200 PHYSICAL PROPERTIES, POTENTIALLY 728 00:30:39,200 --> 00:30:41,440 COULD CREATE TARGETS FOR 729 00:30:41,440 --> 00:30:45,240 INTERVENTION IN THE FUTURE. 730 00:30:45,240 --> 00:30:47,400 PI3 KINASE GAMMA, MYELOID 731 00:30:47,400 --> 00:30:49,040 SPECIFIC VERSION OF PI3 KINASE 732 00:30:49,040 --> 00:30:50,800 IS WELL DESCRIBED TO GENERATE 733 00:30:50,800 --> 00:30:52,960 PUSHING FORCES IN THESE TYPES OF 734 00:30:52,960 --> 00:30:56,520 CELLS, HERE YOU ARE SEEING IN A 735 00:30:56,520 --> 00:30:58,880 NEUTROPHIL BASICALLY THE BRIGHT 736 00:30:58,880 --> 00:31:00,080 INDICATES HIGH PI3 KINASE 737 00:31:00,080 --> 00:31:02,640 ACTIVITY, YOU CAN APPRECIATE THE 738 00:31:02,640 --> 00:31:04,840 CELLS USING THIS BASICALLY 739 00:31:04,840 --> 00:31:05,760 MIGRATES DIRECTIONALLY. 740 00:31:05,760 --> 00:31:07,640 WE KNOW THAT AS I MENTIONED THAT 741 00:31:07,640 --> 00:31:09,400 THIS IS VERY IMPORTANT IN 742 00:31:09,400 --> 00:31:10,840 DEVELOPMENT OF PUSHING FORCES, 743 00:31:10,840 --> 00:31:13,000 THAT COULD ENABLE THE CELLS TO 744 00:31:13,000 --> 00:31:15,000 ACTUALLY SENSE THE SURROUNDING 745 00:31:15,000 --> 00:31:16,360 PHYSICAL PROPERTIES. 746 00:31:16,360 --> 00:31:17,720 SO KYLE DID A SCREEN WHERE HE 747 00:31:17,720 --> 00:31:20,240 LOOKED AT A VARIETY OF 748 00:31:20,240 --> 00:31:22,120 INHIBITORS OF DIFFERENT 749 00:31:22,120 --> 00:31:23,120 POTENTIAL MECHANOTRANSDUCTION 750 00:31:23,120 --> 00:31:25,280 PATHWAYS, IN THIS SCREEN WE DID 751 00:31:25,280 --> 00:31:27,160 A SIMPLE READOUT INITIALLY, 752 00:31:27,160 --> 00:31:30,200 WHICH IS JUST THE ASSEMBLY OF A 753 00:31:30,200 --> 00:31:35,240 CORTICAL F-ACTIN NETWORK. 754 00:31:35,240 --> 00:31:36,800 NORMAL CELLS WHEN WE PUT THEM 755 00:31:36,800 --> 00:31:39,920 INSIDE THE VISCOUS GELS WE DID 756 00:31:39,920 --> 00:31:42,920 NOT GET SIGNIFICANT ASSEMBLY OF 757 00:31:42,920 --> 00:31:44,760 F-ACTIN BUT IN GELS DID, USED 758 00:31:44,760 --> 00:31:48,280 THIS AS A SIMPLE SCREENING. 759 00:31:48,280 --> 00:31:51,280 WHEN WE USED AN INHIBITOR TO 760 00:31:51,280 --> 00:31:55,080 MYELOID KINASE, IN CLINICAL 761 00:31:55,080 --> 00:31:59,640 TRIALS FOR OTHER THINGS, IT 762 00:31:59,640 --> 00:32:01,080 ABROGATED ACTIN ASSEMBLY. 763 00:32:01,080 --> 00:32:03,960 WHEN WE TREATED IN VISCOUS OR 764 00:32:03,960 --> 00:32:07,320 ELASTIC GELS WITH INHIBITOR 765 00:32:07,320 --> 00:32:08,760 HERE, WITHOUT INHIBITOR WE GET 766 00:32:08,760 --> 00:32:11,240 UPREGULATION AS I PREVIOUSLY 767 00:32:11,240 --> 00:32:14,440 NOTED, AND ADDING INHIBITOR 768 00:32:14,440 --> 00:32:15,080 SIGNIFICANTLY ABROGATED EFFECTS 769 00:32:15,080 --> 00:32:18,040 OF THE CHANGE IN 770 00:32:18,040 --> 00:32:19,120 VISCOELASTICITY, SUGGESTING THIS 771 00:32:19,120 --> 00:32:21,000 IS A MECHANISM BY WHICH THE 772 00:32:21,000 --> 00:32:22,200 CELLS ARE SENSING 773 00:32:22,200 --> 00:32:23,840 VISCOELASTICITY AND TRANSDUCING 774 00:32:23,840 --> 00:32:25,800 THIS INTO CHANGES IN GENE 775 00:32:25,800 --> 00:32:27,120 EXPRESSION AND FATE. 776 00:32:27,120 --> 00:32:28,760 NOW, IF WE GO BACK TO THE 777 00:32:28,760 --> 00:32:32,280 STARTING POINT FOR THE STORY FOR 778 00:32:32,280 --> 00:32:33,720 KYLE, WHICH IS MYELOFIBROSIS, 779 00:32:33,720 --> 00:32:37,760 THIS IS A THE MOST AIMPRESSIVE 780 00:32:37,760 --> 00:32:41,840 FORM OF A -- AGGRESSIVE FORM, 781 00:32:41,840 --> 00:32:43,360 MEDIAN PATIENT, MEDIAN SURVIVAL 782 00:32:43,360 --> 00:32:45,280 WITH PRIMARY MF IS ABOUT 6 783 00:32:45,280 --> 00:32:45,640 YEARS. 784 00:32:45,640 --> 00:32:48,440 SO THERE'S CLEARLY AN UNMET NEED 785 00:32:48,440 --> 00:32:50,760 TO DEVELOP IMPROVED TREATMENTS 786 00:32:50,760 --> 00:32:51,680 FOR THESE PATIENTS. 787 00:32:51,680 --> 00:32:53,840 AND SO KYLE WANTED TO EXPLORE 788 00:32:53,840 --> 00:32:57,040 WHETHER THIS KNOWLEDGE WE GAINED 789 00:32:57,040 --> 00:32:59,320 COULD PROVIDE A TARGETABLE 790 00:32:59,320 --> 00:33:00,400 OUTCOME IN THIS CONTEXT. 791 00:33:00,400 --> 00:33:03,800 TO EXPLORE THIS WE WENT TO AN 792 00:33:03,800 --> 00:33:10,000 ANIMAL MODEL OF MYELOFIBROSIS IN 793 00:33:10,000 --> 00:33:10,960 COLLABORATION WITHMAN MULLALLY 794 00:33:10,960 --> 00:33:12,040 AT DANA-FARBER, DISEASES CAUSED 795 00:33:12,040 --> 00:33:15,000 BY MUTATION IN HEMATOPOIETIC 796 00:33:15,000 --> 00:33:16,200 STEM CELLS. 797 00:33:16,200 --> 00:33:20,040 SO WE TALK HEMATOPOIETIC STEM 798 00:33:20,040 --> 00:33:24,840 CELLS THAT WERE MUTATED, 799 00:33:24,840 --> 00:33:25,720 INTRODUCED INTO LETHAL IRRATE 800 00:33:25,720 --> 00:33:27,280 RADIATED RECIPIENTS TO TAKE UP 801 00:33:27,280 --> 00:33:29,880 RESIDENTS IN THE BONE MARROW, 802 00:33:29,880 --> 00:33:32,600 OVER TIME COURSE 6 TO 7 MONTHS 803 00:33:32,600 --> 00:33:33,800 LEADS TO MYELOFIBROSIS, AND THEN 804 00:33:33,800 --> 00:33:35,440 THE HALLMARKS OF THE DISEASE, 805 00:33:35,440 --> 00:33:39,160 FOR EXAMPLE, CHANGES IN BLOOD 806 00:33:39,160 --> 00:33:40,160 CELL COUNTS. 807 00:33:40,160 --> 00:33:42,560 WE WERE ABLE TO TAKE THE BONE 808 00:33:42,560 --> 00:33:48,120 MARROW AT THE ADVANCED STAGE, 809 00:33:48,120 --> 00:33:50,240 CHARACTERIZE MECHANICAL, WHEN WE 810 00:33:50,240 --> 00:33:53,640 INTRODUCE MUTATED CELLS AND 811 00:33:53,640 --> 00:33:55,160 CREATE MYELOFIBROSIS GET 812 00:33:55,160 --> 00:33:57,720 INCREASED STIFFNESS, WE GET 813 00:33:57,720 --> 00:33:58,880 DECREASE IN VISCOELASTICITY OF 814 00:33:58,880 --> 00:34:02,160 THE BONE MARROW INDICATING WE'RE 815 00:34:02,160 --> 00:34:03,840 INDEED GETTING SIGNIFICANT 816 00:34:03,840 --> 00:34:07,680 PHYSICAL CHANGES, NOW WHEN WE 817 00:34:07,680 --> 00:34:08,760 TOOK BASICALLY HISTOLOGICAL 818 00:34:08,760 --> 00:34:10,520 SAMPLES AND PROVIDED THOSE TO A 819 00:34:10,520 --> 00:34:13,440 PATHOLOGIST IN A BLINDED MANNER 820 00:34:13,440 --> 00:34:21,880 AND HAD THEM GRADE DEGREE OF 821 00:34:21,880 --> 00:34:22,640 MYELOFIBROSIS EVEN THOUGH 822 00:34:22,640 --> 00:34:23,640 STIFFNESS CHANGES WITH 823 00:34:23,640 --> 00:34:24,400 DEVELOPMENT THERE'S NO 824 00:34:24,400 --> 00:34:26,120 CORRELATION WITH THE MF GREAT. 825 00:34:26,120 --> 00:34:28,800 IN CONTRAST, THERE WAS A REALLY 826 00:34:28,800 --> 00:34:30,520 STRONG CORRELATION BETWEEN MF 827 00:34:30,520 --> 00:34:35,560 GRADE AND CHANGES IN 828 00:34:35,560 --> 00:34:35,920 VISCOELASTICITY. 829 00:34:35,920 --> 00:34:39,720 SO EXPERIMENT, WENT BACK TO THIS 830 00:34:39,720 --> 00:34:41,680 MODEL, PROVIDED BASICALLY THIS 831 00:34:41,680 --> 00:34:43,000 INHIBITOR, TO THE ANIMALS, WHAT 832 00:34:43,000 --> 00:34:45,080 WE FOUND IS WHEN THE INHIBITOR 833 00:34:45,080 --> 00:34:48,240 WAS PROVIDED TO THESE ANIMALS WE 834 00:34:48,240 --> 00:34:50,000 HAD A SIGNIFICANT DOWNREGULATION 835 00:34:50,000 --> 00:34:51,520 IN THE CIRCULATING INFLAMMATORY 836 00:34:51,520 --> 00:34:56,800 MONOCYTES AND DENDRITIC CELLS 837 00:34:56,800 --> 00:34:57,680 INDICATING ABROGATING ASPECTS OF 838 00:34:57,680 --> 00:34:59,640 THE DISEASE BY INTERVENING IN 839 00:34:59,640 --> 00:35:01,320 THE SIGNALING PATHWAY. 840 00:35:01,320 --> 00:35:02,440 SO HOPEFULLY WHAT I WILL SHOW IN 841 00:35:02,440 --> 00:35:06,600 THIS PART OF THE TALK IS THAT 842 00:35:06,600 --> 00:35:08,120 WHEN WE HAVE IMMATURE MONOCYTES 843 00:35:08,120 --> 00:35:10,440 AND THEY ARE IN A MORE 844 00:35:10,440 --> 00:35:11,520 VISCOELASTIC MATRIX WHAT WE 845 00:35:11,520 --> 00:35:13,360 BELIEVE HAPPENS IS THEY GENERATE 846 00:35:13,360 --> 00:35:16,560 PUSHING FORCES, BUT THE MATERIAL 847 00:35:16,560 --> 00:35:18,160 ITSELF WILL BASICALLY FLOW, 848 00:35:18,160 --> 00:35:20,240 DISSIPATE THE STRESSES, AND SO 849 00:35:20,240 --> 00:35:22,880 THE CELL DOESN'T BASICALLY GET 850 00:35:22,880 --> 00:35:23,480 STRESSED MECHANICALLY. 851 00:35:23,480 --> 00:35:27,040 IN CONTRAST IN THE MORE ELASTIC 852 00:35:27,040 --> 00:35:33,240 MATRIX WHEN THE CELL PUSHES, IT 853 00:35:33,240 --> 00:35:34,040 DOESN'T DISSIPATE, INSTEAD 854 00:35:34,040 --> 00:35:34,640 STORES THEM, BASICALLY PUSHES 855 00:35:34,640 --> 00:35:36,280 BACK ON THE CELL. 856 00:35:36,280 --> 00:35:38,320 THE CELL ACTUALLY SENSES THIS 857 00:35:38,320 --> 00:35:39,080 THROUGH THIS ONE PARTICULAR 858 00:35:39,080 --> 00:35:39,440 PATHWAY. 859 00:35:39,440 --> 00:35:42,920 SO WE THINK WE'VE IDENTIFIED A 860 00:35:42,920 --> 00:35:43,760 TARGETABLE MECHANICAL CHECKPOINT 861 00:35:43,760 --> 00:35:47,160 IN THE CONTEXT OF AT LEAST THIS 862 00:35:47,160 --> 00:35:48,040 PARTICULAR DISEASE. 863 00:35:48,040 --> 00:35:49,560 NOW, THE LAST PART OF WHAT I'D 864 00:35:49,560 --> 00:35:51,640 LIKE TO TALK TO YOU A LITTLE BIT 865 00:35:51,640 --> 00:35:53,840 ABOUT IS KIND OF THE MOST RECENT 866 00:35:53,840 --> 00:35:56,040 FORAY INTO THIS SPACE, NOW 867 00:35:56,040 --> 00:35:57,160 UNPUBLISHED DATA. 868 00:35:57,160 --> 00:35:59,440 WHERE WE'VE BEEN INTERESTED IN 869 00:35:59,440 --> 00:36:01,400 WHETHER ACTUALLY OTHER IMMUNE 870 00:36:01,400 --> 00:36:04,800 CELLS, PARTICULARLY T CELLS, MAY 871 00:36:04,800 --> 00:36:08,640 ALSO BE IMPACTED BY CHANGES IN 872 00:36:08,640 --> 00:36:11,040 MATRIX VISCOELASTICITY. 873 00:36:11,040 --> 00:36:15,960 WE'RE ALL FAMILIAR WITH 874 00:36:15,960 --> 00:36:17,040 LIMITATION OF T CELL 875 00:36:17,040 --> 00:36:17,800 IMMUNOTHERAPY IN CONTEXT OF 876 00:36:17,800 --> 00:36:19,360 SOLID TUMORS, BELIEVED TO BE A 877 00:36:19,360 --> 00:36:20,880 NUMBER OF BARRIERS TO THE 878 00:36:20,880 --> 00:36:27,160 EFFECTIVE INSIDE -- EFFECTIVEN, 879 00:36:27,160 --> 00:36:28,800 BASICALLY DIFFICULTIES IN CELLS 880 00:36:28,800 --> 00:36:30,200 ACCESSING TUMORS. 881 00:36:30,200 --> 00:36:31,240 YOU KNOW, DIVERSE 882 00:36:31,240 --> 00:36:32,840 IMMUNOSUPPRESSION THAT HAPPENS 883 00:36:32,840 --> 00:36:35,160 WITHIN THE TUMOR 884 00:36:35,160 --> 00:36:36,680 MICROENVIRONMENT, AS WELL AS 885 00:36:36,680 --> 00:36:37,920 ANTIGEN HETEROGENEITY. 886 00:36:37,920 --> 00:36:39,840 WHAT WE BEGAN TO EXPLORE, 887 00:36:39,840 --> 00:36:41,480 WHETHER ADDITIONAL FEATURE OF 888 00:36:41,480 --> 00:36:46,080 THIS COULD BE CHANGES IN THE 889 00:36:46,080 --> 00:36:48,200 MATRIX VISCOELASTICITY MAY ALSO 890 00:36:48,200 --> 00:36:52,400 ALTER T CELL PHENOTYPE AND 891 00:36:52,400 --> 00:36:53,120 EFFECTIVENESS DIRECTLY. 892 00:36:53,120 --> 00:36:57,600 TO DO A REALITY CHECK ON THIS 893 00:36:57,600 --> 00:36:58,480 CONCEPT, TO START WITH, A 894 00:36:58,480 --> 00:36:59,680 Ph.D. STUDENT IN THE 895 00:36:59,680 --> 00:37:01,080 LABORATORY SHOWN HERE WHO HAS 896 00:37:01,080 --> 00:37:03,600 TAKEN A STAFF POSITION AT THE 897 00:37:03,600 --> 00:37:04,800 WYSS INSTITUTE STARTED BASICALLY 898 00:37:04,800 --> 00:37:08,360 BY GOING BACK TO PATIENT DATA, 899 00:37:08,360 --> 00:37:10,080 SINGLE CELL RNAseq DATA, AND 900 00:37:10,080 --> 00:37:12,960 HE JUST DID SOMETHING RELATIVELY 901 00:37:12,960 --> 00:37:14,400 STRAIGHTFORWARD WHICH IS LOOKED 902 00:37:14,400 --> 00:37:16,120 AT BASICALLY THE GENE EXPRESSION 903 00:37:16,120 --> 00:37:18,520 OF T CELLS IN THREE CANCERS WE 904 00:37:18,520 --> 00:37:19,800 COULD OBTAIN DATA FOR, AND 905 00:37:19,800 --> 00:37:21,920 COMPARED THE GENE EXPRESSION OF 906 00:37:21,920 --> 00:37:24,000 THE T CELLS IN BLOOD, WHICH 907 00:37:24,000 --> 00:37:25,960 WOULD BE VISCOUS FLUID, AND 908 00:37:25,960 --> 00:37:27,840 NORMAL TISSUE, WHICH WE WOULD 909 00:37:27,840 --> 00:37:30,240 EXPECT TO BE A VISCOELASTIC 910 00:37:30,240 --> 00:37:31,560 SOLID, AND THEN IN TUMORS WHICH 911 00:37:31,560 --> 00:37:33,840 WE WOULD THINK WOULD BE MORE 912 00:37:33,840 --> 00:37:34,200 ELASTIC. 913 00:37:34,200 --> 00:37:37,280 AND WHAT HE FOUND WAS THAT 914 00:37:37,280 --> 00:37:39,000 BASICALLY THE PATTERNS OF GENE 915 00:37:39,000 --> 00:37:39,800 EXPRESSION WERE DRAMATICALLY 916 00:37:39,800 --> 00:37:42,440 ALTERED FOR T CELLS IN THESE 917 00:37:42,440 --> 00:37:43,200 THREE DIFFERENT ENVIRONMENTS. 918 00:37:43,200 --> 00:37:45,040 SO FOR EXAMPLE HERE WE'RE 919 00:37:45,040 --> 00:37:48,440 LOOKING AT ONE BASIC EXPRESSION 920 00:37:48,440 --> 00:37:49,880 OF A BASICALLY THE GENE SET 921 00:37:49,880 --> 00:37:51,960 INDICATIVE OF CELLS AND TUMORS, 922 00:37:51,960 --> 00:37:55,120 YOU CAN SEE IT'S UPREGULATED FOR 923 00:37:55,120 --> 00:37:59,080 ALL THREE OF THESE BASICALLY 924 00:37:59,080 --> 00:38:05,600 TYPE OFS CANCER CAN -- TYPES O. 925 00:38:05,600 --> 00:38:07,240 THE ONLY DIFFERENCE BETWEEN 926 00:38:07,240 --> 00:38:08,240 BLOOD AND TUMOR TISSUE, THERE'S 927 00:38:08,240 --> 00:38:14,160 A LOT OF DIFFERENCE IN PHYSICAL 928 00:38:14,160 --> 00:38:16,040 PROPERTIES BUT THIS SUGGESTS 929 00:38:16,040 --> 00:38:16,920 PERHAPS CHANGING PHYSICAL 930 00:38:16,920 --> 00:38:19,400 PROPERTIES COULD RELATE TO SOME 931 00:38:19,400 --> 00:38:21,280 ALTERATIONS IN T CELL PHENOTYPE. 932 00:38:21,280 --> 00:38:24,280 TO GET AT THIS MECHANISTICALLY 933 00:38:24,280 --> 00:38:27,520 WENT BACK TO 3D MODEL SYSTEM, 934 00:38:27,520 --> 00:38:29,280 AND HERE HE TOOK WHAT KYLE HAD 935 00:38:29,280 --> 00:38:31,560 DONE AND TOOK IT ONE STEP 936 00:38:31,560 --> 00:38:34,640 FURTHER FORWARD, WHICH IS HE 937 00:38:34,640 --> 00:38:38,560 USED THIS IDEA OF SMALL COVALENT 938 00:38:38,560 --> 00:38:40,200 CROSS-LINKING MOLECULES THAT 939 00:38:40,200 --> 00:38:41,200 COULD ONLY CROSS-LINK POLYMERS 940 00:38:41,200 --> 00:38:43,280 THAT WERE ALREADY IN CLOSE 941 00:38:43,280 --> 00:38:45,240 PROXIMITY, FOR EXAMPLE ALREADY 942 00:38:45,240 --> 00:38:47,600 ASSEMBLED, AND HE CREATED PURELY 943 00:38:47,600 --> 00:38:51,480 COLLAGEN GELS HERE, LET THE 944 00:38:51,480 --> 00:38:53,800 COLLAGEN BASICALLY FIBRIL 945 00:38:53,800 --> 00:38:57,400 ASSEMBLY OCCUR, WOULD DIFFUSE IN 946 00:38:57,400 --> 00:39:00,480 BASICALLY A VERY SMALL DIVALENT 947 00:39:00,480 --> 00:39:05,920 CROSS-LINKER TO CROSS-LINK 948 00:39:05,920 --> 00:39:10,880 COLLAGEN IN CLOSE PROXIMITY 949 00:39:10,880 --> 00:39:14,760 CREATING FAST OR SLOW GELS. 950 00:39:14,760 --> 00:39:16,560 THE ARCHITECTURE WAS UNALTERED. 951 00:39:16,560 --> 00:39:19,000 AND THE BASICALLY PORE SIZE WAS 952 00:39:19,000 --> 00:39:20,560 UNALTERED INDICATED BY IMAGING. 953 00:39:20,560 --> 00:39:22,920 HERE YOU'RE LOOKING AT 954 00:39:22,920 --> 00:39:24,160 QUANTIFICATION OF THICKNESS AND 955 00:39:24,160 --> 00:39:26,120 PORE DIAMETER SO WE CAN CHANGE 956 00:39:26,120 --> 00:39:27,840 JUST THE VISCOELASTICITY WITHOUT 957 00:39:27,840 --> 00:39:29,720 CHANGING THOSE OTHER FEATURES, 958 00:39:29,720 --> 00:39:34,400 AND WE CAN MATCH BASICALLY THE 959 00:39:34,400 --> 00:39:37,040 STIFFNESS AND HAVE VARYING RATES 960 00:39:37,040 --> 00:39:38,040 OF STRESS RELAXATION. 961 00:39:38,040 --> 00:39:41,960 HE WOULD ADD MORE COLLAGEN TO 962 00:39:41,960 --> 00:39:42,960 CHANGE STIFFNESS, COMPARING 963 00:39:42,960 --> 00:39:44,240 STIFFNESS LEVELS THERE'S THIS 964 00:39:44,240 --> 00:39:45,240 ADDITIONAL FEATURE BUT ONLY 965 00:39:45,240 --> 00:39:47,200 COMPARED MORE OR LESS VISCOUS 966 00:39:47,200 --> 00:39:50,280 THAT IS ACTUALLY INDEPENDENT OF 967 00:39:50,280 --> 00:39:52,000 ANY OTHER VARIABLES. 968 00:39:52,000 --> 00:39:53,560 AND THEN IN COLLABORATION WITH A 969 00:39:53,560 --> 00:39:56,280 CURRENT Ph.D. STUDENT IN THE 970 00:39:56,280 --> 00:39:59,600 LABORATORY ENCAPSULATED T CELLS 971 00:39:59,600 --> 00:40:01,880 WITHIN THESE GELS THAT WOULD BE 972 00:40:01,880 --> 00:40:04,960 EITHER SOFT OR STIFF, AND EITHER 973 00:40:04,960 --> 00:40:06,880 BASICALLY FAST RELAXING, MEANING 974 00:40:06,880 --> 00:40:08,040 MORE VISCOELASTIC, OR SLOW 975 00:40:08,040 --> 00:40:10,320 RELAXING, AND WHAT YOU CAN 976 00:40:10,320 --> 00:40:13,120 APPRECIATE FROM THESE PLOTS IS 977 00:40:13,120 --> 00:40:14,160 THEY NOTICE SIGNIFICANT 978 00:40:14,160 --> 00:40:15,600 ALTERATION IN PHENOTYPE OF T 979 00:40:15,600 --> 00:40:18,360 CELLS, AS HERE INDICATED BY 980 00:40:18,360 --> 00:40:21,400 EXPRESSION OF CD45 RA, CD62L, 981 00:40:21,400 --> 00:40:23,480 AND INDEED IF THEY LOOK AT A 982 00:40:23,480 --> 00:40:25,800 NUMBER OF DIFFERENT KEY FEATURES 983 00:40:25,800 --> 00:40:28,040 OF T CELL BIOLOGY, AND THEN 984 00:40:28,040 --> 00:40:31,360 LOOKED AT HOW THEY WERE 985 00:40:31,360 --> 00:40:32,680 EXPRESSED RELATIVELY IN THESE 986 00:40:32,680 --> 00:40:35,640 DIFFERENT SETTINGS, ONE CAN SEE 987 00:40:35,640 --> 00:40:38,040 ONE GETS DRAMATIC ALTERATION IN 988 00:40:38,040 --> 00:40:40,240 EXPRESSION OF THESE MARKERS AS 989 00:40:40,240 --> 00:40:42,520 ONE TRANSITIONS BETWEEN THE MORE 990 00:40:42,520 --> 00:40:45,720 ELASTIC AND MORE VISCOELASTIC 991 00:40:45,720 --> 00:40:46,560 SUBSTRATES. 992 00:40:46,560 --> 00:40:49,400 ACTUALLY EFFECTS OF 993 00:40:49,400 --> 00:40:50,960 VISCOELASTICITY WERE MUCH MORE 994 00:40:50,960 --> 00:40:52,160 SIGNIFICANT THAN EFFECTS OF 995 00:40:52,160 --> 00:40:53,560 CHANGING STIFFNESS. 996 00:40:53,560 --> 00:40:58,400 NOW, THEY ALSO DID SOME SINGLE 997 00:40:58,400 --> 00:40:59,360 CELL RNAseq, YOU CAN 998 00:40:59,360 --> 00:41:01,000 APPRECIATE THE T CELLS IN THE 999 00:41:01,000 --> 00:41:03,760 FAST RELAXING AND SLOW RELAXING 1000 00:41:03,760 --> 00:41:08,480 GELS OCCUPY DIFFERENT LOCATIONS 1001 00:41:08,480 --> 00:41:10,840 IN THIS UMAP REPRESENTATION. 1002 00:41:10,840 --> 00:41:12,080 IF WE PULL EXPRESSION IMPORTANT 1003 00:41:12,080 --> 00:41:13,840 IN T CELL BIOLOGY AND EFFECTOR 1004 00:41:13,840 --> 00:41:16,840 FUNCTION YOU CAN SEE THERE IS A 1005 00:41:16,840 --> 00:41:18,320 SIGNIFICANT ALTERATION IN GENE 1006 00:41:18,320 --> 00:41:23,240 EXPRESSION AS WE GO FROM FAST 1007 00:41:23,240 --> 00:41:25,360 RELAXING TO GELS. 1008 00:41:25,360 --> 00:41:28,000 IF WE DO CONSENSUS 1009 00:41:28,000 --> 00:41:29,960 FACTORIZATION, YOU CAN SEE WE 1010 00:41:29,960 --> 00:41:37,400 HAVE A VARIETY OF PATHWAYS 1011 00:41:37,400 --> 00:41:41,000 UPREGULATED, T-CELL RECEPTOR 1012 00:41:41,000 --> 00:41:42,400 SIGNALING, CYTOTOXIC RESPONSE, 1013 00:41:42,400 --> 00:41:45,280 MEDIATED CELL DEATH, WE'RE 1014 00:41:45,280 --> 00:41:46,560 GETTING ALTERATIONS IN MANY 1015 00:41:46,560 --> 00:41:48,280 GENES WE WOULD EXPECT WOULD BE 1016 00:41:48,280 --> 00:41:49,640 RELEVANT TO THE EFFECTIVENESS OF 1017 00:41:49,640 --> 00:41:54,680 T CELLS IN CONTEXT OF CANCER. 1018 00:41:54,680 --> 00:41:57,520 NOW, WE CAN ACTUALLY GENERATE 1019 00:41:57,520 --> 00:41:58,840 BASICALLY GENE EXPRESSION 1020 00:41:58,840 --> 00:42:01,920 MODULES, THAT REPRESENT CELLS IN 1021 00:42:01,920 --> 00:42:03,960 THE FAST OR SLOW RELAXING GELS, 1022 00:42:03,960 --> 00:42:06,960 FOR EXAMPLE THESE TWO MODULES 1023 00:42:06,960 --> 00:42:10,840 BASICALLY REPRESENT CELLS IN THE 1024 00:42:10,840 --> 00:42:12,200 FAST RELAXING GEL, THESE IN THE 1025 00:42:12,200 --> 00:42:12,400 SLOW. 1026 00:42:12,400 --> 00:42:14,440 WE CAN SEE THEY ARE 1027 00:42:14,440 --> 00:42:15,040 DIFFERENTIALLY EXPRESSED IN 1028 00:42:15,040 --> 00:42:16,560 POPULATIONS IN THE UMAP 1029 00:42:16,560 --> 00:42:20,480 REPRESENTATION, BUT THEN MORE 1030 00:42:20,480 --> 00:42:22,280 IMPORTANTLY, HE TOOK GENE 1031 00:42:22,280 --> 00:42:26,320 MODULES AND WENT BACK TO THAT 1032 00:42:26,320 --> 00:42:27,640 PRIMARY PATIENT DATA, WITH 1033 00:42:27,640 --> 00:42:29,840 DIFFERENT TYPES OF CANCER, IN 1034 00:42:29,840 --> 00:42:31,800 THIS CASE EXPANDED INCLUDING 1035 00:42:31,800 --> 00:42:32,920 BREAST CANCER DATASET THAT 1036 00:42:32,920 --> 00:42:34,120 BECAME AVAILABLE. 1037 00:42:34,120 --> 00:42:38,480 HE LOOKED FOR EXPRESSION OF THIS 1038 00:42:38,480 --> 00:42:40,000 SLOW MODULE IN THESE PATIENT 1039 00:42:40,000 --> 00:42:41,200 DERIVED T CELLS. 1040 00:42:41,200 --> 00:42:43,040 WHAT YOU CAN APPRECIATE IN ALL 1041 00:42:43,040 --> 00:42:44,800 FOUR TYPES OF CANCER THAT THIS 1042 00:42:44,800 --> 00:42:46,160 MODULE OF GENE EXPRESSION THAT 1043 00:42:46,160 --> 00:42:49,320 WE FOUND IN OUR IN VITRO MODEL 1044 00:42:49,320 --> 00:42:52,240 IN THE MORE ELASTIC GELS WAS 1045 00:42:52,240 --> 00:42:54,320 SIGNIFICANTLY OVEREXPRESSED IN T 1046 00:42:54,320 --> 00:42:55,480 CELLS WITHIN TUMORS THAT WE ALSO 1047 00:42:55,480 --> 00:42:57,240 WOULD EXPECT TO BE MORE ELASTIC 1048 00:42:57,240 --> 00:43:00,280 THAN IN THE BLOOD OR NORMAL 1049 00:43:00,280 --> 00:43:00,640 TISSUE. 1050 00:43:00,640 --> 00:43:01,840 AGAIN, SUPPORTING THE IDEA THAT 1051 00:43:01,840 --> 00:43:04,000 THERE MAY BE SOME REAL 1052 00:43:04,000 --> 00:43:05,360 PHYSIOLOGIC OR PATHOLOGICAL 1053 00:43:05,360 --> 00:43:09,280 RELEVANCE TO THESE CELL CULTURE 1054 00:43:09,280 --> 00:43:10,240 MODELS THAT WE'RE THEN 1055 00:43:10,240 --> 00:43:10,520 EXPLORING. 1056 00:43:10,520 --> 00:43:12,440 ANOTHER POSSIBILITY HERE FOR 1057 00:43:12,440 --> 00:43:13,800 THIS DATA, FOR ALL DATA 1058 00:43:13,800 --> 00:43:15,960 ACTUALLY, IS THAT INSTEAD OF 1059 00:43:15,960 --> 00:43:17,920 CHANGING THE GENE EXPRESSION OF 1060 00:43:17,920 --> 00:43:19,680 T CELLS, WE MIGHT BE SELECTING 1061 00:43:19,680 --> 00:43:23,080 FOR CERTAIN CLONES OF T CELLS IN 1062 00:43:23,080 --> 00:43:24,960 THE DIFFERENT MICROENVIRONMENTAL 1063 00:43:24,960 --> 00:43:25,640 CONDITIONS. 1064 00:43:25,640 --> 00:43:27,680 SO IF ONE REDOES THIS ANALYSIS 1065 00:43:27,680 --> 00:43:30,120 ON THE LEFT, BUT ACTUALLY DOES 1066 00:43:30,120 --> 00:43:35,560 IT ONLY FOR T CELLS OF SHARED 1067 00:43:35,560 --> 00:43:37,200 CLONOTYPE ONE SEES THE SAME 1068 00:43:37,200 --> 00:43:39,320 RESULT, NOT JUST A SELECTION 1069 00:43:39,320 --> 00:43:40,880 PROCESS FOR CERTAIN BASICALLY 1070 00:43:40,880 --> 00:43:43,000 CLONOTYPES OF T CELLS, I WON'T 1071 00:43:43,000 --> 00:43:44,520 GO THROUGH THE DATA, BUT NOW 1072 00:43:44,520 --> 00:43:46,400 THIS IS GOING BACK TO OUR CELL 1073 00:43:46,400 --> 00:43:48,160 CULTURE MODEL WITH T CELLS IN 1074 00:43:48,160 --> 00:43:51,520 THE FAST AND SLOW RELAXING GELS, 1075 00:43:51,520 --> 00:43:52,960 AND NET OUTCOME HERE IS THAT 1076 00:43:52,960 --> 00:43:55,600 WE'RE NOT GETTING ANY EFFECTS ON 1077 00:43:55,600 --> 00:43:57,480 SPECIFIC T CELL CLONES BY 1078 00:43:57,480 --> 00:43:58,640 ENCAPSULATING CELLS IN THESE 1079 00:43:58,640 --> 00:44:00,080 DIFFERENT GELS. 1080 00:44:00,080 --> 00:44:02,920 AGAIN, DOES NOT APPEAR WE'RE 1081 00:44:02,920 --> 00:44:04,760 CHANGING CLONOTYPES OR 1082 00:44:04,760 --> 00:44:06,400 PREFERRING CERTAIN CLONOTYPES 1083 00:44:06,400 --> 00:44:07,280 BUT ALTERING GENE EXPRESSION 1084 00:44:07,280 --> 00:44:13,880 ACROSS THE BOARD OF THESE T CELL 1085 00:44:13,880 --> 00:44:14,760 POPULATIONS. 1086 00:44:14,760 --> 00:44:15,400 WHAT WE'RE INTERESTED IN 1087 00:44:15,400 --> 00:44:19,120 UNDERSTANDING WHETHER THIS HAS 1088 00:44:19,120 --> 00:44:23,480 IMPACT ON FUNCTION OF T CELLS N 1089 00:44:23,480 --> 00:44:27,240 CONTEXT OF CANCER. 1090 00:44:27,240 --> 00:44:29,720 WE DID KILLING STUDDIE, T CELLS, 1091 00:44:29,720 --> 00:44:32,240 ACTIVATED, PUT INTO FAST OR SLOW 1092 00:44:32,240 --> 00:44:34,880 RELAXING GELS, LOOKED AT ABILITY 1093 00:44:34,880 --> 00:44:36,200 TO KILL THEIR TARGET CANCER 1094 00:44:36,200 --> 00:44:38,600 CELL, THIS IS IN CELL CULTURE 1095 00:44:38,600 --> 00:44:39,400 INITIALLY. 1096 00:44:39,400 --> 00:44:49,800 HERE LOOKING AT PERCENT 1097 00:44:55,640 --> 00:44:55,840 CYTOLYSIS. 1098 00:44:55,840 --> 00:44:59,040 THE CELLS BASICALLY IN THE STIFF 1099 00:44:59,040 --> 00:45:00,440 SLOW-RELAXING GELS WERE VERY 1100 00:45:00,440 --> 00:45:02,080 EFFECTIVE AT KILLING THE CANCER 1101 00:45:02,080 --> 00:45:04,280 CELLS, REGARDLESS OF THE LEVEL 1102 00:45:04,280 --> 00:45:07,480 OF STIMULATION, WHILE THE CELLS 1103 00:45:07,480 --> 00:45:09,120 BASICALLY IN THE FAST-RELAXING 1104 00:45:09,120 --> 00:45:12,360 GELS WERE LESS EFFECTIVE AT 1105 00:45:12,360 --> 00:45:12,680 KILLING. 1106 00:45:12,680 --> 00:45:14,680 IF WE LOOKED AT EXPRESSION OF A 1107 00:45:14,680 --> 00:45:17,200 NUMBER OF MARKERS OF THESE 1108 00:45:17,200 --> 00:45:21,040 CELLS, BASICALLY IN THIS ASSAY, 1109 00:45:21,040 --> 00:45:24,200 COMPARE AGAIN BASICALLY THE SLOW 1110 00:45:24,200 --> 00:45:25,520 AND FAST-RELAXING GELS, DURING 1111 00:45:25,520 --> 00:45:28,400 LEVELS OF STIMULATION, YOU CAN 1112 00:45:28,400 --> 00:45:30,640 AGAIN SEE DRAMATIC ALTERATIONS. 1113 00:45:30,640 --> 00:45:33,400 FOR EXAMPLE IN THE STIFF SLOW 1114 00:45:33,400 --> 00:45:37,800 RELAXING AND MORE ELASTIC GELS 1115 00:45:37,800 --> 00:45:39,440 YOU SEE UPREGULATION, AS 1116 00:45:39,440 --> 00:45:41,600 COMPARED TO THE CELLS BASICALLY 1117 00:45:41,600 --> 00:45:44,000 IN THE SAME STIFFNESS BUT FAST 1118 00:45:44,000 --> 00:45:46,520 RELAXING GEL. 1119 00:45:46,520 --> 00:45:50,200 AGAIN, SUPPORTING THAT BASICALLY 1120 00:45:50,200 --> 00:45:51,240 THE CYTOLYSIS DATA. 1121 00:45:51,240 --> 00:45:54,200 TO SEE IF THIS TRANSLATED IN 1122 00:45:54,200 --> 00:45:56,680 VIVO WE TOOK T CELLS, PUT THEM 1123 00:45:56,680 --> 00:45:59,200 INTO EITHER FAST OR SLOW 1124 00:45:59,200 --> 00:46:01,720 RELAXING GELS, FOR SEVERAL DAYS, 1125 00:46:01,720 --> 00:46:03,840 REMOVED THEM, AND DID AN 1126 00:46:03,840 --> 00:46:04,440 ADOPTIVE TRANSFER. 1127 00:46:04,440 --> 00:46:07,240 THIS WAS IN THE CONTEXT OF CAR T 1128 00:46:07,240 --> 00:46:09,520 CELLS. 1129 00:46:09,520 --> 00:46:11,920 HUMAN CAR T CELLS. 1130 00:46:11,920 --> 00:46:14,760 WE'RE BASICALLY PUTTING IN 1131 00:46:14,760 --> 00:46:16,400 IMMUNOCOMPROMISE THE ANIMALS 1132 00:46:16,400 --> 00:46:18,360 THAT RECEIVED RAW CELLS, CLASSIC 1133 00:46:18,360 --> 00:46:20,760 CAR T MODEL SYSTEM FOR 1134 00:46:20,760 --> 00:46:21,800 DEVELOPMENT OF THOSE PRODUCTS, 1135 00:46:21,800 --> 00:46:24,440 AND YOU CAN SEE IF WE DON'T DO 1136 00:46:24,440 --> 00:46:26,160 ANY ADOPTIVE TRANSFER OF THE CAR 1137 00:46:26,160 --> 00:46:28,760 T CELLS THE ANIMALS ALL RAPIDLY 1138 00:46:28,760 --> 00:46:32,400 SUCCUMB TO DISEASE, IF WE 1139 00:46:32,400 --> 00:46:36,640 INTRODUCE T CELLS THAT WERE IN A 1140 00:46:36,640 --> 00:46:38,200 MORE VISCOELASTIC SUBSTRATE, 1141 00:46:38,200 --> 00:46:40,160 THEY PROVIDE SOME CONTROL, BUT 1142 00:46:40,160 --> 00:46:44,680 THE CONTROL IS LOST, ANIMALS 1143 00:46:44,680 --> 00:46:45,680 WILL SUCCUMB. 1144 00:46:45,680 --> 00:46:46,960 IF THE HAVE THE SAME NUMBER OF T 1145 00:46:46,960 --> 00:46:51,320 CELLS IN A MORE ELASTIC 1146 00:46:51,320 --> 00:46:54,080 MICROENVIRONMENT BEFORE ADOPTIVE 1147 00:46:54,080 --> 00:46:56,800 TRANSFER THEY DO A MUCH BETTER 1148 00:46:56,800 --> 00:47:00,560 JOB OF CONTROLLING DISEASE 1149 00:47:00,560 --> 00:47:04,160 PROGRESSION AND ENHANCEMENT OF 1150 00:47:04,160 --> 00:47:05,440 SURVIVAL IN THIS SETTINGS. 1151 00:47:05,440 --> 00:47:06,800 CHANGES DO SEEM TO HAVE IMPACT 1152 00:47:06,800 --> 00:47:11,160 ON ABILITY OF T CELLS TO 1153 00:47:11,160 --> 00:47:12,160 ACTUALLY HAVE EFFECTIVE 1154 00:47:12,160 --> 00:47:14,320 PHENOTYPE AND FUNCTION IN AN 1155 00:47:14,320 --> 00:47:14,720 EFFECTIVE MANNER. 1156 00:47:14,720 --> 00:47:17,280 SO I'M GOING TO WRAP UP HERE. 1157 00:47:17,280 --> 00:47:21,440 HOPEFULLY WHAT I'VE BEEN ABLE TO 1158 00:47:21,440 --> 00:47:22,640 DEMONSTRATE IS THAT MATRIX 1159 00:47:22,640 --> 00:47:23,400 VISCOELASTICITY CAN INDEED 1160 00:47:23,400 --> 00:47:25,280 IMPACT THE FATE AND PHENOTYPE OF 1161 00:47:25,280 --> 00:47:29,200 MULTIPLE CELL TYPES THAT ARE 1162 00:47:29,200 --> 00:47:29,960 RELATIVE, RELEVANT FOR CANCER, 1163 00:47:29,960 --> 00:47:31,600 INCLUDING MANY FOUND IN TUMORS. 1164 00:47:31,600 --> 00:47:35,320 REMINDER, THIS IS WHAT WE MEAN 1165 00:47:35,320 --> 00:47:36,760 BY MORE VISCOUS, PERMANENT 1166 00:47:36,760 --> 00:47:37,960 DEFORMATION OF MATERIAL BECAUSE 1167 00:47:37,960 --> 00:47:39,600 THE MATERIAL FLOWS WHEN WE 1168 00:47:39,600 --> 00:47:41,440 BASICALLY PUSH OR PULL ON IT. 1169 00:47:41,440 --> 00:47:43,440 SO WHAT I'VE BEEN ABLE TO SHOW 1170 00:47:43,440 --> 00:47:44,400 HOPEFULLY IN THE DIFFERENT 1171 00:47:44,400 --> 00:47:54,880 ELEMENTS OF THE TALK IS THAT 1172 00:47:57,920 --> 00:47:59,120 MONOCYTE DIFFERENTIATION, 1173 00:47:59,120 --> 00:48:00,120 PRE-CANCEROUS CELLS AND CANCER 1174 00:48:00,120 --> 00:48:02,920 CELLS, ONE PIECE OF DATA, THEY 1175 00:48:02,920 --> 00:48:04,200 ARE IMPACTED AS WELL. 1176 00:48:04,200 --> 00:48:08,440 I DID NOT SHOW BUT WE'VE SEEN 1177 00:48:08,440 --> 00:48:11,640 SIMILAR EFFECTS WITH MSCs, 1178 00:48:11,640 --> 00:48:13,000 DRAMATIC CHANGE IN IMMUNOMONO 1179 00:48:13,000 --> 00:48:14,200 PHENOTYPE AS WE CHANGE 1180 00:48:14,200 --> 00:48:16,200 VISCOELASTICITY AND FINISHED BY 1181 00:48:16,200 --> 00:48:17,600 DEMONSTRATING HOW T EFFECTOR 1182 00:48:17,600 --> 00:48:19,880 CELL BIOLOGY IS ALSO 1183 00:48:19,880 --> 00:48:22,640 DRAMATICALLY IMPACTED BY THIS 1184 00:48:22,640 --> 00:48:23,600 ALTERATION IN MATRIX 1185 00:48:23,600 --> 00:48:23,960 VISCOELASTICITY. 1186 00:48:23,960 --> 00:48:25,800 I'LL FINISH HERE AND HOPEFULLY 1187 00:48:25,800 --> 00:48:30,600 THE TAKEHOME MESSAGE IS THAT 1188 00:48:30,600 --> 00:48:35,200 MATRIX VISCOELASTIC SUBSTRATE I 1189 00:48:35,200 --> 00:48:37,160 S -- MATRIX VISCOELASTICITY IS 1190 00:48:37,160 --> 00:48:38,440 SOMETHING WE WANT TO CONSIDER IN 1191 00:48:38,440 --> 00:48:39,080 CANCER BIOLOGY. 1192 00:48:39,080 --> 00:48:40,560 THANK YOU FOR YOUR ATTENTION, 1193 00:48:40,560 --> 00:48:42,200 AND I'D BE HAPPY TO TAKE ANY 1194 00:48:42,200 --> 00:48:42,480 QUESTIONS. 1195 00:48:42,480 --> 00:48:42,800 >>ALL RIGHT. 1196 00:48:42,800 --> 00:48:44,280 THANK YOU VERY MUCH. 1197 00:48:44,280 --> 00:48:48,560 EXCELLENT TALK. 1198 00:48:48,560 --> 00:48:51,840 SO LET'S GET TO IT FOR THE Q&A 1199 00:48:51,840 --> 00:48:55,880 PART OF OUR SESSION. 1200 00:48:55,880 --> 00:48:57,480 SO, IN YOUR TUNEABLE ALGINATE 1201 00:48:57,480 --> 00:49:00,480 MODEL TO WHAT EXTENT CAN YOU 1202 00:49:00,480 --> 00:49:02,240 VARY CALCIUM CONCENTRATION TO 1203 00:49:02,240 --> 00:49:04,760 NOT AFFECT THE CELLS WHETHER 1204 00:49:04,760 --> 00:49:06,400 CALCIUM IS TIGHTLY REGULATED FOR 1205 00:49:06,400 --> 00:49:08,360 ELECTRICAL ACTIVITY IN MANY CELL 1206 00:49:08,360 --> 00:49:08,560 TYPES? 1207 00:49:08,560 --> 00:49:09,120 >>YEAH, THAT'S ALWAYS A 1208 00:49:09,120 --> 00:49:10,960 QUESTION THAT COMES UP WITH THE 1209 00:49:10,960 --> 00:49:11,400 SYSTEM. 1210 00:49:11,400 --> 00:49:13,840 YEAH, SO IF ONE VARIES CALCIUM, 1211 00:49:13,840 --> 00:49:15,240 THAT CAN IMPACT CELLS, MANY 1212 00:49:15,240 --> 00:49:16,040 DIFFERENT WAYS. 1213 00:49:16,040 --> 00:49:17,800 IN ALL THESE EXPERIMENTS I'M 1214 00:49:17,800 --> 00:49:19,080 DESCRIBING TODAY, WE HAVE A 1215 00:49:19,080 --> 00:49:20,840 VARIETY OF CONTROL CONDITIONS I 1216 00:49:20,840 --> 00:49:22,680 DIDN'T SHOW HERE. 1217 00:49:22,680 --> 00:49:24,480 SO, FOR EXAMPLE, WE ADD 1218 00:49:24,480 --> 00:49:27,000 BASICALLY MORE CALCIUM TO THE 1219 00:49:27,000 --> 00:49:28,160 MEDIA TO SHOW BASICALLY OVER THE 1220 00:49:28,160 --> 00:49:29,480 RANGES WE'RE TALKING ABOUT HERE 1221 00:49:29,480 --> 00:49:32,560 WE DON'T SEE IMPACT OF THE 1222 00:49:32,560 --> 00:49:33,240 CALCIUM ITSELF. 1223 00:49:33,240 --> 00:49:36,120 ONE THING TO KEEP IN MIND IS 1224 00:49:36,120 --> 00:49:39,880 CALCIUM HERE IS BOUND BY 1225 00:49:39,880 --> 00:49:40,880 POLYSACCHARIDES, NOT FREE 1226 00:49:40,880 --> 00:49:42,360 CALCIUM AVAILABLE FOR UPTAKE. 1227 00:49:42,360 --> 00:49:45,200 WE BASICALLY FIND THAT THESE 1228 00:49:45,200 --> 00:49:48,560 EFFECTS WE'RE DESCRIBE ARE ARE 1229 00:49:48,560 --> 00:49:51,040 INDEPENDENT OF ANY MINOR CHANGES 1230 00:49:51,040 --> 00:49:52,600 IN CALCIUM, IN THE MEDIA. 1231 00:49:52,600 --> 00:49:54,000 BUT IT'S ALWAYS SOMETHING ONE 1232 00:49:54,000 --> 00:49:59,920 DOES NEED TO CHECK, ONE DOES 1233 00:49:59,920 --> 00:50:00,840 NEED TO CONFIRM. 1234 00:50:00,840 --> 00:50:01,080 >>GREAT. 1235 00:50:01,080 --> 00:50:05,080 SO I HAVE A QUESTION FOR THE 1236 00:50:05,080 --> 00:50:06,880 COLLAGEN INCORPORATING MODEL. 1237 00:50:06,880 --> 00:50:15,560 NOW, HOW IS THAT INTERACTING 1238 00:50:15,560 --> 00:50:18,880 WITH YOUR ALGINATE HYDRAGEL 1239 00:50:18,880 --> 00:50:22,040 NETWORK, IS IT ASSEMBLING, 1240 00:50:22,040 --> 00:50:26,200 FORMING FIBRILS, ARE THEY 1241 00:50:26,200 --> 00:50:36,720 INTERCONGESTION -- INTERDIG 1242 00:50:37,680 --> 00:50:37,800 TATE? 1243 00:50:37,800 --> 00:50:39,800 >>IN THAT CONFECTION AS LONG AS 1244 00:50:39,800 --> 00:50:41,760 WE CONTROL THE KINETICS IT'S 1245 00:50:41,760 --> 00:50:43,840 COMPLICATED BECAUSE WE HAVE 1246 00:50:43,840 --> 00:50:46,040 KINETICS OF THE ALGINATE 1247 00:50:46,040 --> 00:50:47,880 CROSS-LINKING, ALSO HAVE 1248 00:50:47,880 --> 00:50:58,400 KINETICS OF THE COLLAGEN FIBRIL 1249 00:51:02,280 --> 00:51:03,440 ASSEMBLY, FORMATION HAPPENS 1250 00:51:03,440 --> 00:51:06,400 EQUIVALENTLY IN ALL THE GELS 1251 00:51:06,400 --> 00:51:08,840 BEFORE YOU GET THE ALGINATE 1252 00:51:08,840 --> 00:51:10,000 CROSS-LINKING HAPPENING AROUND 1253 00:51:10,000 --> 00:51:10,560 IT. 1254 00:51:10,560 --> 00:51:13,920 IF WE HAVE COVALENT FIRST THAT 1255 00:51:13,920 --> 00:51:15,480 CAN INHIBIT COLLAGEN ASSEMBLY, 1256 00:51:15,480 --> 00:51:20,320 SO WE CONTROL THE KINETICS OF 1257 00:51:20,320 --> 00:51:24,760 THESE THREE ASPECTS, THE 1258 00:51:24,760 --> 00:51:30,240 QUESTION EQUIVALENT FIBRIL 1259 00:51:30,240 --> 00:51:31,800 COLLAGEN FORMATION, IT'S 1260 00:51:31,800 --> 00:51:35,160 EQUIVALENT, BUT ALGINATE MORE OR 1261 00:51:35,160 --> 00:51:36,600 LESS MECHANICALLY SUPPORTS THE 1262 00:51:36,600 --> 00:51:39,240 COLLAGEN, AND IT DICTATES 1263 00:51:39,240 --> 00:51:40,200 CHANGES IN STIFFNESS AND 1264 00:51:40,200 --> 00:51:43,400 VISCOELASTICITY BY CONTROLLING 1265 00:51:43,400 --> 00:51:46,680 THE CROSS-LINKING, IONIC VERSUS 1266 00:51:46,680 --> 00:51:47,480 COVALENT CROSS-LINKING. 1267 00:51:47,480 --> 00:51:48,720 >>BASICALLY ALGINATE IS 1268 00:51:48,720 --> 00:51:49,840 DOMINATING MECHANICAL PROPERTIES 1269 00:51:49,840 --> 00:51:50,680 IN THAT INSTANT? 1270 00:51:50,680 --> 00:51:52,720 >>YES, ABSOLUTELY. 1271 00:51:52,720 --> 00:51:53,000 YEP. 1272 00:51:53,000 --> 00:51:56,080 AND THAT'S ONE -- IN RELATION TO 1273 00:51:56,080 --> 00:51:57,160 EARLIER QUESTION, IN THOSE 1274 00:51:57,160 --> 00:52:00,560 STUDIES AS WE VARY THE EXTENT OF 1275 00:52:00,560 --> 00:52:01,440 VISCOELASTICITY ACTUALLY THE 1276 00:52:01,440 --> 00:52:02,440 CALCIUM CONTENT IN GELS IS 1277 00:52:02,440 --> 00:52:04,760 EXACTLY THE SAME BETWEEN ONE AND 1278 00:52:04,760 --> 00:52:05,880 THE NEXT, WE'RE BASICALLY 1279 00:52:05,880 --> 00:52:09,480 VARYING -- ADDING A LITTLE BIT 1280 00:52:09,480 --> 00:52:17,120 OF CLICK CHEMISTRY TO ALTER THE 1281 00:52:17,120 --> 00:52:18,880 BASICALLY VISCOELASTICITY. 1282 00:52:18,880 --> 00:52:22,720 >>ANOTHER QUESTION REGARDING 1283 00:52:22,720 --> 00:52:31,040 THE DYNAMICS BETWEEN YOUR HYDRA 1284 00:52:31,040 --> 00:52:31,160 G 1285 00:52:31,160 --> 00:52:33,200 EL SYSTEM ARE THEY 1286 00:52:33,200 --> 00:52:34,400 CHANGING THE MECHANICS OF THE 1287 00:52:34,400 --> 00:52:35,560 MATRIX, IF YOU TEST PROPERTIES 1288 00:52:35,560 --> 00:52:41,840 AFTER CELLS HAVE BEEN IN THERE, 1289 00:52:41,840 --> 00:52:42,480 DOES THAT CHANGE? 1290 00:52:42,480 --> 00:52:45,040 >>IT'S A HARD THING TO 1291 00:52:45,040 --> 00:52:46,360 CHARACTERIZE, LOOKING AT VERY 1292 00:52:46,360 --> 00:52:47,240 LOCALIZED EFFECTS. 1293 00:52:47,240 --> 00:52:50,080 WE KNOW THERE'S NO GROSS EFFECT. 1294 00:52:50,080 --> 00:52:51,480 IF WE MONITOR MACROSCALE 1295 00:52:51,480 --> 00:52:53,480 PROPERTIES OVER TIME, THEY DON'T 1296 00:52:53,480 --> 00:52:53,800 CHANGE. 1297 00:52:53,800 --> 00:52:54,880 BUT WE WOULDN'T EXPECT THAT. 1298 00:52:54,880 --> 00:52:57,720 I THINK THE QUESTION IS MORE 1299 00:52:57,720 --> 00:52:57,960 LOCALLY. 1300 00:52:57,960 --> 00:52:59,800 NOW, ONE THING WE DO KNOW, IT'S 1301 00:52:59,800 --> 00:53:02,440 VERY IMPORTANT, IS THE CELLS ARE 1302 00:53:02,440 --> 00:53:04,840 ACTIVELY REMODELING THE 1303 00:53:04,840 --> 00:53:05,360 MATERIALS. 1304 00:53:05,360 --> 00:53:06,720 FOR EXAMPLE, ACTUALLY SOME VERY 1305 00:53:06,720 --> 00:53:10,000 EARLY WORK WITH THESE SYSTEMS 1306 00:53:10,000 --> 00:53:12,520 GOING BACK TO LIKE 2015 OR 1307 00:53:12,520 --> 00:53:15,600 SOMETHING LIKE THIS, WE 1308 00:53:15,600 --> 00:53:18,320 DEMONSTRATED THAT THE RGD 1309 00:53:18,320 --> 00:53:19,720 LIGANDS ON POLYMERS GET 1310 00:53:19,720 --> 00:53:21,360 CLUSTERED BY CELLS, REACHING OUT 1311 00:53:21,360 --> 00:53:25,760 AND GRABBING, PULLING, AND SINCE 1312 00:53:25,760 --> 00:53:26,880 THE MATERIAL CAN FLOW, CELLS 1313 00:53:26,880 --> 00:53:29,720 DEFORM IT AND DO CHANGE IT. 1314 00:53:29,720 --> 00:53:31,680 ONE EARLY QUESTION WAS, SO IF 1315 00:53:31,680 --> 00:53:34,400 THEY ARE REMODELING, ARE THEY 1316 00:53:34,400 --> 00:53:37,920 REALLY JUST PULLING ENOUGH 1317 00:53:37,920 --> 00:53:39,640 POLYMER AROUND THEMSELVES THAT 1318 00:53:39,640 --> 00:53:41,520 MAYBE THEY ARE STIFFENING, MAYBE 1319 00:53:41,520 --> 00:53:43,800 WE'RE LIKING AT STIFFENING VIA 1320 00:53:43,800 --> 00:53:44,600 DIFFERENT MECHANISM. 1321 00:53:44,600 --> 00:53:47,000 SOME OTHER DATA I SHOWED YOU 1322 00:53:47,000 --> 00:53:49,720 TODAY INDICATES THAT THAT'S 1323 00:53:49,720 --> 00:53:51,720 LIKELY NOT -- STRONGLY INDICATES 1324 00:53:51,720 --> 00:53:53,440 IT'S NOT HAPPENING. 1325 00:53:53,440 --> 00:53:54,360 WE'VE DONE SOME INDIRECT 1326 00:53:54,360 --> 00:53:55,960 ANALYSIS OF THAT. 1327 00:53:55,960 --> 00:53:59,800 FOR EXAMPLE, WE LOOK AT OVERALL 1328 00:53:59,800 --> 00:54:02,400 GENE EXPRESSION, RNAseq, THAT 1329 00:54:02,400 --> 00:54:04,360 IF THE EFFECTS OF 1330 00:54:04,360 --> 00:54:06,000 VISCOELASTICITY WERE REALLY TO 1331 00:54:06,000 --> 00:54:07,960 ALLOW LOCAL STIFFENING, THEN YOU 1332 00:54:07,960 --> 00:54:10,280 WOULD EXPECT THE PATTERN OF GENE 1333 00:54:10,280 --> 00:54:11,360 EXPRESSION TO BE SIMILAR WHETHER 1334 00:54:11,360 --> 00:54:13,360 WE START WITH GELS THAT HAVE 1335 00:54:13,360 --> 00:54:14,760 DIFFERENT STIFFNESS OR WHETHER 1336 00:54:14,760 --> 00:54:17,400 THE CELLS MAKE THEM INTO 1337 00:54:17,400 --> 00:54:19,360 SOMETHING THAT HAS DIFFERENT 1338 00:54:19,360 --> 00:54:21,000 STIFFNESS AND FIND PATTERNS OF 1339 00:54:21,000 --> 00:54:21,880 GENE EXPRESSION AND DIFFERENTIAL 1340 00:54:21,880 --> 00:54:22,960 GENE EXPRESSION INDUCED BY 1341 00:54:22,960 --> 00:54:25,480 CHANGES IN STIFFNESS AND CHANGES 1342 00:54:25,480 --> 00:54:26,600 IN VISCOELASTICITY ARE LARGELY 1343 00:54:26,600 --> 00:54:27,800 ORTHOGONAL TO EACH OTHER. 1344 00:54:27,800 --> 00:54:29,640 WE'RE NOT GETTING MUCH OVERLAP 1345 00:54:29,640 --> 00:54:30,640 IN TERMS OF GENES GETTING 1346 00:54:30,640 --> 00:54:32,600 IMPACTED, HOW THEY ARE GETTING 1347 00:54:32,600 --> 00:54:34,000 IMPACTED, YOU KNOW, AGAIN 1348 00:54:34,000 --> 00:54:35,200 SUPPORTING VISCOELASTICITY IS 1349 00:54:35,200 --> 00:54:38,880 REALLY ACTING BY A DIFFERENT 1350 00:54:38,880 --> 00:54:46,480 MECHANISM, AND ONE OF THE FORMER 1351 00:54:46,480 --> 00:54:48,360 POSTDOCS HAS DOCUMENTED 1352 00:54:48,360 --> 00:54:50,080 SIGNALING PATHWAYS RELATED TO 1353 00:54:50,080 --> 00:54:51,080 VISCOELASTICITY THAT ARE 1354 00:54:51,080 --> 00:54:52,800 DISTINCT FROM CHANGES IN 1355 00:54:52,800 --> 00:54:53,080 STIFFNESS. 1356 00:54:53,080 --> 00:54:56,440 >>YEAH, A RELATED QUESTION THAT 1357 00:54:56,440 --> 00:54:58,840 JUST CAME IN ACTUALLY. 1358 00:54:58,840 --> 00:55:00,960 THE CELLS THEMSELVES ARE 1359 00:55:00,960 --> 00:55:01,440 VISCOELASTIC, CORRECT? 1360 00:55:01,440 --> 00:55:02,240 >>OH, YEAH. 1361 00:55:02,240 --> 00:55:02,440 YES. 1362 00:55:02,440 --> 00:55:07,160 >>YOU KNOW, HOW DOES THAT 1363 00:55:07,160 --> 00:55:08,120 COMPLICATE THIS MODELING OF 1364 00:55:08,120 --> 00:55:09,480 THIS -- TRYING TO UNDERSTAND 1365 00:55:09,480 --> 00:55:10,200 WHAT'S GOING ON HERE? 1366 00:55:10,200 --> 00:55:12,520 >>YEAH, SO THE CELLS THEMSELVES 1367 00:55:12,520 --> 00:55:16,160 ARE VISCOELASTIC, AND WE KNOW 1368 00:55:16,160 --> 00:55:18,160 THAT CELL STIFFNESS IS ALTERED 1369 00:55:18,160 --> 00:55:28,520 AS ONE PUTS CELLS INTO 1370 00:55:30,240 --> 00:55:30,640 ENVIRONMENTS, MATRICES. 1371 00:55:30,640 --> 00:55:38,960 TO THE BEST OF MY KNOWLEDGE NO 1372 00:55:38,960 --> 00:55:40,480 ONE LOOKED AT VISCOELASTIC 1373 00:55:40,480 --> 00:55:41,800 BEHAVIOR BUT I EXPECT IT WILL 1374 00:55:41,800 --> 00:55:42,080 BE. 1375 00:55:42,080 --> 00:55:46,760 AT THIS POINT IT'S UNKNOWN. 1376 00:55:46,760 --> 00:55:47,080 >>GOTCHA. 1377 00:55:47,080 --> 00:55:49,680 OKAY. 1378 00:55:49,680 --> 00:55:56,000 AND SO A QUESTION FOR THE 1379 00:55:56,000 --> 00:55:58,000 MONOCYTE DIFFERENTIATION 1380 00:55:58,000 --> 00:56:00,600 EXPERIMENTS, ELASTIC VERSUS 1381 00:56:00,600 --> 00:56:02,160 VISCOUS ENVIRONMENTS, WAS THERE 1382 00:56:02,160 --> 00:56:05,640 ANY PUSH TOWARDS THAT M1/M2 1383 00:56:05,640 --> 00:56:06,800 PHENOTYPE IN THE CELLS? 1384 00:56:06,800 --> 00:56:10,040 >>YEAH, NO, WE REALLY DIDN'T 1385 00:56:10,040 --> 00:56:12,920 SEE MUCH MACROPHAGE 1386 00:56:12,920 --> 00:56:13,800 DIFFERENTIATION IN THAT SETTING. 1387 00:56:13,800 --> 00:56:17,280 >>GOTCHA. 1388 00:56:17,280 --> 00:56:18,720 AND -- GREAT. 1389 00:56:18,720 --> 00:56:22,840 SO A QUESTION LATER ABOUT THE T 1390 00:56:22,840 --> 00:56:26,720 CELLS AND SPECIFICALLY THE HUMAN 1391 00:56:26,720 --> 00:56:28,680 DATASETS THAT YOU COMPARED. 1392 00:56:28,680 --> 00:56:32,400 IS THERE A WAY TO DISSECT OUT 1393 00:56:32,400 --> 00:56:35,360 THE OTHER MICROENVIRONMENTAL 1394 00:56:35,360 --> 00:56:37,640 FACTORS SUCH AS CYTOKINE MILIEU 1395 00:56:37,640 --> 00:56:41,040 WHEN COMPARING DIFFERENT TISSUES 1396 00:56:41,040 --> 00:56:41,440 LIKE THAT? 1397 00:56:41,440 --> 00:56:42,800 >>SO, WE MADE NO EFFORT TO DO 1398 00:56:42,800 --> 00:56:43,120 IT. 1399 00:56:43,120 --> 00:56:44,720 AS I HAD MENTIONED DURING THE 1400 00:56:44,720 --> 00:56:47,080 TALK THERE'S A LOT OF 1401 00:56:47,080 --> 00:56:48,880 DIFFERENCES BETWEEN BLOOD AND 1402 00:56:48,880 --> 00:56:50,120 NORMAL TISSUE, TUMORS. 1403 00:56:50,120 --> 00:56:53,400 SO WE DON'T TAKE THAT DATA AS 1404 00:56:53,400 --> 00:56:54,920 SHOWING CAUSE AND EFFECT. 1405 00:56:54,920 --> 00:56:57,800 BUT IT'S QUITE STRIKING THAT THE 1406 00:56:57,800 --> 00:56:59,760 CHANGES IN GENE EXPRESSION WE 1407 00:56:59,760 --> 00:57:02,160 SEE WHEN WE KEEP EVERYTHING 1408 00:57:02,160 --> 00:57:03,680 CONSTANT, ONLY CHANGE THE 1409 00:57:03,680 --> 00:57:05,760 VISCOELASTICITY, WE GET SIMILAR 1410 00:57:05,760 --> 00:57:07,200 CHANGES IN GENE EXPRESSION AS 1411 00:57:07,200 --> 00:57:09,680 YOU LOOK AT CELLS TRANSITIONING 1412 00:57:09,680 --> 00:57:11,240 BETWEEN THE THREE COMPARTMENTS 1413 00:57:11,240 --> 00:57:12,240 IN THE BODY. 1414 00:57:12,240 --> 00:57:14,520 CERTAINLY A LOT OF THINGS IMPACT 1415 00:57:14,520 --> 00:57:16,040 THE CELLS. 1416 00:57:16,040 --> 00:57:20,280 BUT THAT DATA SUGGESTS THAT 1417 00:57:20,280 --> 00:57:20,880 VISCOELASTICITY, EFFECTS OF 1418 00:57:20,880 --> 00:57:23,080 VISCOELASTICITY, YOU KNOW, MAY 1419 00:57:23,080 --> 00:57:24,600 BE MIRRORED IN PATIENTS AND 1420 00:57:24,600 --> 00:57:25,480 PATIENT SAMPLES AS WELL. 1421 00:57:25,480 --> 00:57:27,880 IN TERMS OF HOW YOU CAN DO THAT, 1422 00:57:27,880 --> 00:57:29,520 YOU CERTAINLY COULD ATTEMPT TO 1423 00:57:29,520 --> 00:57:31,000 DO THAT, YOU KNOW, WITH THE 1424 00:57:31,000 --> 00:57:31,960 HUMAN PATIENT DATA, I DON'T 1425 00:57:31,960 --> 00:57:33,600 THINK YOU COULD, BUT YOU COULD 1426 00:57:33,600 --> 00:57:36,360 CERTAINLY, YOU KNOW, TRY TO DO 1427 00:57:36,360 --> 00:57:38,600 THAT KIND OF DECOUPLING IN 1428 00:57:38,600 --> 00:57:42,800 MURINE MODELS, YOU KNOW, WITH 1429 00:57:42,800 --> 00:57:43,360 VARIOUS TRANSGENICS. 1430 00:57:43,360 --> 00:57:44,560 >>THAT'S THE BEAUTY OF IN VITRO 1431 00:57:44,560 --> 00:57:45,760 MODEL, RIGHT? 1432 00:57:45,760 --> 00:57:48,640 YOU CAN TAKE OUT A LOT OF THOSE 1433 00:57:48,640 --> 00:57:49,080 VARIABLES. 1434 00:57:49,080 --> 00:57:49,480 >>YES. 1435 00:57:49,480 --> 00:57:53,400 AND REALLY THE NEED HERE IS 1436 00:57:53,400 --> 00:57:55,840 ESPECIALLY WHEN TALKING ABOUT 1437 00:57:55,840 --> 00:57:59,120 IMPACT OF PHYSICAL PROPERTIES, 1438 00:57:59,120 --> 00:58:00,920 EXTRACELLULAR MATRIX, NO WAY I'M 1439 00:58:00,920 --> 00:58:05,240 AWARE OF TO PERTURB 1440 00:58:05,240 --> 00:58:05,760 VISCOELASTICITY WITHOUT 1441 00:58:05,760 --> 00:58:06,680 SIMULTANEOUSLY CHANGING 1442 00:58:06,680 --> 00:58:08,760 STIFFNESS AND MOST LIKELY 1443 00:58:08,760 --> 00:58:09,480 IMPACTING BIOCHEMICAL 1444 00:58:09,480 --> 00:58:10,960 COMPOSITION OF EXTRACELLULAR 1445 00:58:10,960 --> 00:58:13,120 MATRIX. 1446 00:58:13,120 --> 00:58:15,320 SO IT'S NOT THAT WE PREFER IN 1447 00:58:15,320 --> 00:58:16,720 THESE IN VITRO MODELS OVER IN 1448 00:58:16,720 --> 00:58:18,480 VIVO, BUT IF YOU WANT TO GET A 1449 00:58:18,480 --> 00:58:19,680 CAUSE AND EFFECT I THINK THE 1450 00:58:19,680 --> 00:58:21,840 ONLY WAY YOU CAN DO THAT IS BY 1451 00:58:21,840 --> 00:58:22,760 USING THESE TYPES OF IN VITRO 1452 00:58:22,760 --> 00:58:25,920 MOD 1453 00:58:25,920 --> 00:58:27,680 MODELS WITH TIGHT AND 1454 00:58:27,680 --> 00:58:28,320 INDEPENDENT CONTROL OVER 1455 00:58:28,320 --> 00:58:31,920 VARIABLES, LOOK TO SEE IF 1456 00:58:31,920 --> 00:58:34,520 THERE'S SUPPORT FOR FINDINGS IN 1457 00:58:34,520 --> 00:58:36,120 PATIENT-DERIVED SAMPLES AND IN 1458 00:58:36,120 --> 00:58:36,640 VIVO MODELS. 1459 00:58:36,640 --> 00:58:36,920 >>GREAT. 1460 00:58:36,920 --> 00:58:40,800 WE HAVE TIME FOR ONE MORE 1461 00:58:40,800 --> 00:58:41,360 QUESTION. 1462 00:58:41,360 --> 00:58:42,240 I'LL TAKE THIS OPPORTUNITY AND 1463 00:58:42,240 --> 00:58:47,840 BEAR WITH ME AS I ACCESS OLD 1464 00:58:47,840 --> 00:58:48,440 COURSE KNOWLEDGE. 1465 00:58:48,440 --> 00:58:48,680 >>OKAY. 1466 00:58:48,680 --> 00:58:55,240 >>SO, HAVE YOU THOUGHT ABOUT 1467 00:58:55,240 --> 00:58:56,040 OTHER VISCOELASTIC PROPERTIES 1468 00:58:56,040 --> 00:58:58,480 SUCH AS CREEP AND THING LIKE 1469 00:58:58,480 --> 00:58:59,880 THAT WHERE, YOU KNOW, WHEN YOU 1470 00:58:59,880 --> 00:59:02,720 THINK, AS I'M THINKING ABOUT 1471 00:59:02,720 --> 00:59:06,680 THIS, YOU KNOW, IS THE CELL 1472 00:59:06,680 --> 00:59:08,120 TRYING TO KEEP TENSION CONSTANT 1473 00:59:08,120 --> 00:59:09,640 OR SHAPE OR COMBINATION OF BOTH? 1474 00:59:09,640 --> 00:59:11,840 WHAT ARE YOUR THOUGHTS ON THOSE 1475 00:59:11,840 --> 00:59:12,360 OTHER PROPERTIES? 1476 00:59:12,360 --> 00:59:14,920 >>YEAH, NO, IT'S A REALLY 1477 00:59:14,920 --> 00:59:15,880 INTERESTING AND IMPORTANT 1478 00:59:15,880 --> 00:59:16,200 QUESTION. 1479 00:59:16,200 --> 00:59:17,840 YOU KNOW, CREEP IS BASICALLY FOR 1480 00:59:17,840 --> 00:59:20,800 THOSE WHO ARE NOT FAMILIAR, 1481 00:59:20,800 --> 00:59:23,320 CREEP IS THE FLIP SIDE OF STRESS 1482 00:59:23,320 --> 00:59:25,960 RELAXATION. 1483 00:59:25,960 --> 00:59:28,480 IN A CREEP STUDY YOU MAINTAIN 1484 00:59:28,480 --> 00:59:29,880 STRESS AND FOLLOW DEFORMATION. 1485 00:59:29,880 --> 00:59:31,760 THEN IN A VISCOELASTIC MATERIAL 1486 00:59:31,760 --> 00:59:32,920 THE DEFORMATION WILL THEN 1487 00:59:32,920 --> 00:59:34,480 CONTINUE TO INCREASE WITH TIME 1488 00:59:34,480 --> 00:59:35,880 IN ESSENCE AS MATERIAL FLOWS 1489 00:59:35,880 --> 00:59:38,520 UNDER THAT STRESS OR FORCE. 1490 00:59:38,520 --> 00:59:41,600 YEAH, THE QUESTION IS DO CELLS 1491 00:59:41,600 --> 00:59:44,880 KEEP A CONSTANT -- DO THEY APPLY 1492 00:59:44,880 --> 00:59:47,520 CONSTANT FORCE OR CONSTANT 1493 00:59:47,520 --> 00:59:47,760 STRAIN? 1494 00:59:47,760 --> 00:59:49,440 IT'S NOT CLEAR. 1495 00:59:49,440 --> 00:59:51,960 YOU KNOW, WHICH IS BASICALLY 1496 00:59:51,960 --> 00:59:53,440 PROBABLY MORE RELEVANT. 1497 00:59:53,440 --> 00:59:54,400 IT'S QUITE STRAIGHTFORWARD. 1498 00:59:54,400 --> 00:59:56,360 ACTUALLY I MEAN THE BEHAVIOR IS 1499 00:59:56,360 --> 00:59:58,760 LARGELY MIRRORED BETWEEN THE 1500 00:59:58,760 --> 01:00:01,200 STRESS RELAXATION IN A CREEP 1501 01:00:01,200 --> 01:00:02,040 TEST. 1502 01:00:02,040 --> 01:00:03,920 SO WE FIND BASICALLY 1503 01:00:03,920 --> 01:00:04,800 CHARACTERIZATION VIA HALFTIME 1504 01:00:04,800 --> 01:00:06,880 FOR STRESS RELAXATION TO BE A 1505 01:00:06,880 --> 01:00:09,160 VERY CONVENIENT WAY OF 1506 01:00:09,160 --> 01:00:10,120 CHARACTERIZING VISCOELASTIC 1507 01:00:10,120 --> 01:00:11,120 BEHAVIOR AND COMPARING IT. 1508 01:00:11,120 --> 01:00:14,760 SO WE DO THAT BUT WHETHER IT 1509 01:00:14,760 --> 01:00:16,520 TRULY IS THE APPROPRIATE METRIC 1510 01:00:16,520 --> 01:00:17,960 OR WHETHER CREEP MIGHT BE MORE 1511 01:00:17,960 --> 01:00:20,760 RELEVANT I THINK WE DON'T KNOW. 1512 01:00:20,760 --> 01:00:22,520 THERE'S ACTUALLY SOME DATA, YOU 1513 01:00:22,520 --> 01:00:24,400 KNOW, IN CELL CULTURE STUDIES 1514 01:00:24,400 --> 01:00:27,120 FOR BOTH BEING RELEVANT. 1515 01:00:27,120 --> 01:00:28,640 >>ALL RIGHT. 1516 01:00:28,640 --> 01:00:31,040 WELL, THAT'S ABOUT IT FOR TIME. 1517 01:00:31,040 --> 01:00:32,040 THANK YOU AGAIN. 1518 01:00:32,040 --> 01:00:33,120 I REALLY ENJOYED THE TALK TODAY. 1519 01:00:33,120 --> 01:00:34,280 AND A ROUND OF APPLAUSE TO YOU. 1520 01:00:34,280 --> 01:00:35,360 I'M SURE EVERYONE WATCHING FROM 1521 01:00:35,360 --> 01:00:36,640 YOUR LAB. 1522 01:00:36,640 --> 00:00:00,000 >>MY PLEASURE.