>>WELCOME TO A COMBINED
WEDNESDAY AFTERNOON LECTURE
SERIES AND DEMYSTIFYING MEDICINE
LECTURE TODAY.
THIS IS THE 12TH DEMYSTIFYING
MEDICINE TOPIC OF THE YEAR, AND
WE'RE IN OUR 21ST YEAR.
SO THE GOAL OF BOTH OF THESE
ACTIVITIES, THE WALS AND THE
DEMYSTIFYING MEDICINE, IS TO
BRIDGE AND EXCITE YOU WITH
DEVELOPMENTS IN BIOLOGY, AND
TODAY, THE TOPIC IS ENGINEERING,
EXCITING BRIDGING THIS WITH
MEDICINE.
THIS IS THE LOGO, THE BROOKLYN
BRIDGE.
WE AS ALWAYS ARE LIKE THE
INDIVIDUALS ON THE CATWALK, AND
TODAY, WE'RE GOING TO HEAR FROM
A LEADING BIOENGINEER, AND WE'RE
INTERESTED IN ITS RELATIONSHIP
OF HER WORK TO MEDICINE, AND
THAT'S THE TOPIC.
THIS IS A COURSE IN BRIDGE
BUILDING.
NEXT SLIDE.
ANOTHER WAY OF EXPRESSING THE
SAME IDEA WAS BY PROFESSOR
KOLLATH, A EUROPEAN BIOCHEMIST
IN THE EARLY 20TH CENTURY WHO
SAID, TRANSLATED: MUCH IS
KNOWN, BUT UNFORTUNATELY IN
DIFFERENT HEADS.
SO ONE OF THE PURPOSES OF
DEMYSTIFYING MEDICINE IS TO
EXCHANGE INFORMATION AND BRING
TOGETHER KNOWLEDGE INTO AREAS
THAT OTHERWISE WE WOULDN'T KNOW.
TODAY WE ARE FORTUNATE TO HAVE
WITH US SANGEETA BHATIA, WHO IS
TREUL LIE AN IS
A EXTRAORDINARY BRIDGE BUILDER.
HER RESEARCH GOAL HAS BEEN TO
ENGINEER MICRO AND
NANOTECHNOLOGIES TO ADDRESS
COMPLEX CHALLENGES IN HUMAN
HEALTH INCLUDING CANCER, LIVER
DISEASE, AND ACQUIRED
INFECTIONS.
THE NEXT SLIDE.
SOMETHING ABOUT SANGEETA, SHE IS
A PERSON OF EXTRAORDINARY
ACCOMPLISHMENT.
I THINK OF HER SOMETIMES AS A
COLLECTOR.
FOR EXAMPLE, SHE HAS
COLLECTED DEGREES LISTED ON THE
TOP OF THE SLIDE.
AND HAS A PH.D. IN BIOMEDICAL
ENGINEERING FROM THE HEALTH
SCIENCE TECHNOLOGY PROGRAM.
TENURED AT UCSD, THEN RETURNED
TO MIT, WHERE SHE IS THE WILSON
PROFESSOR OF HEALTH SCIENCE AND
TECHNOLOGY, THE DIRECTOR OF THE
MARBLE CENTER FOR CANCER STUDIES
WITH NANOMEDICINE.
SHE'S A HOWARD HUGHES
INVESTIGATOR, AND A MEMBER OF
THE BROAD AND THE WYSS
INSTITUTES.
SANGEETA HAS RECEIVED
EXTRAORDINARY RECOGNITION.
I'LL JUST MENTION A FEW.
SHE RECEIVED THE LEMELSON-MIT
AWARD REFERRED TO AS THE OSCAR
FOR INVENTORS, AND THE HEINZ
AWARD FOR INVENTIONS IN
ADVOCACY.
SANGEETA IS A POWERFUL ADVOCATE
FOR WOMEN, FOR DIVERSITY AND FOR
HIGH STANDARDS IN ALL OF OUR
ACTIVITIES.
EXTRAORDINARILY ENOUGH, SHE'S
THE ONLY PERSON I KNOW WHO'S
BEEN ELECTED TO ALL FIVE
NATIONAL ACADEMIES: OF SCIENCE,
ENGINEERING, MEDICINE, ARTS AND
SCIENCE, AND INVENTORS.
IN ADDITION, SHE HAS CRITICAL
BOARD MEMBERSHIPS, ADVISORY
COMMITTEES AND CONSULTING, AND
WE ARE REALLY MOST PLEASED AND
DELIGHTED TO HAVE YOU WITH US
TODAY, SANGEETA, AND SHE WILL
SPEAK TO US ABOUT TINY
TECHNOLOGIES AND MEDICINE: FROM
HEPATIC TISSUE ENGINEERING TO
CANCER NANOTECHNOLOGY.
SANGEETA?
>> THANK YOU, WIN.
I JUST WANTED TO THANK WIN
AND THE ORGANIZERS FOR THIS
DOUBLEHEADER TODAY, DOING BOTH
WALS AND DEMYSTIFYING MEDICINE.
IT'S A REAL TREAT TO SHARE MY
PERSPECTIVES AND TO SEE YOU ALL
VIRTUALLY, AND I'M LOOKING
FORWARD TO THE DAY WHEN WE CAN
ALL MEET IN PERSON.
BUT TECHNOLOGY HAS SOME
ADVANTAGES, WHICH IS THAT WE GET
TO REACH A WIDER AUDIENCE.
SO THE STORY I'LL BE TELLING YOU
TODAY IS, AS WIN DESCRIBED, A
STORY ABOUT USING ENGINEERING
TOOLS TO TACKLE PROBLEMS IN
BIOMEDICAL RESEARCH, AS WELL AS
NEW POTENTIAL INVENTIONS TO
ADDRESS UNMET MEDICAL NEEDS.
AND I'LL BE TELLING YOU ABOUT
OUR WORK IN LIVER TISSUE
ENGINEERING AND CANCER
NANOTECHNOLOGY.
THESE ARE MY REQUIRED
DISCLOSURES.
I DO WANT TO HIGHLIGHT THAT I'LL
BE SHOWING DATA FROM TWO
STARTUPS: GLYMPSE AND SAT LIE
BIOTHAT RELATE TO MY WORK AND I
AM AN EQUITY HOLDER IN THOSE
ESTABLISHMENTS.
OKAY.
SO MY KIND OF PLAY SAND BOX HAS
BEEN THE WORLD OF TINY
TECHNOLOGIES.
AND JUST TO SORT OF GET US ALL
ON THE SAME PAGE ABOUT WHAT THAT
MEANS, WHAT I'M REFERRING TO ARE
THE TECHNOLOGIES OF MICRO AND
NANOTECHNOLOGY THAT REALLY GREW
OUT OF THE SEMICONDUCTOR
INDUSTRY.
SO HERE YOU CAN SEE ONE MARBLE
THAT THIS HAS GIVEN US, AND THAT
IS THAT ONE TRANSISTOR USED TO
BE THE SIZE THAT YOU SEE ON THE
LEFT.
AND WE CAN NOW FIT A BILLION OF
THOSE ON THE SAME FOOTPRINT.
AND THAT'S THROUGH AGGRESSIVE
MINIATURIZATION OF SEMICONDUCTOR
TECHNOLOGY.
THAT HAS, OF COURSE,
MINIATURIZED COMPUTATION AND
CHANGE TO ALL OF OUR LIVES,
REALLY.
SO IF WE LOOK BACK AND THINK
ABOUT HOW THAT HAPPENED, YOU
KNOW, BEGINNING IN THE 1960s
UP TO THE 2000s, THE CIRCUITS
THAT ARE WRITTEN ON SILICON
SEMICONDUCTOR CHIPS WITH LIGHT
HAVE GOTTEN SMALLER AND SMALLER.
AND STARTING IN THE YEAR 2000,
WE STARTED TO BE ABLE TO MAKE
FEATURES ON THESE CHIPS THAT
WERE SMALLER THAN 100
NANOMETERS.
AND ACTUALLY IN 2020, IN THE
LATEST SMARTPHONE, THEY'RE
SMALLER THAN 5 NANOMETERS.
SO WE CAN DRAW INCREDIBLY TINY
FEATURES IN WHAT'S CALLED
TOP-DOWN FABRICATION.
START WITH A BIG THING AND YOU
WRITE SMALL THINGS ON IT.
NOW THIS ADVANCE HAS BEEN
COUPLED BY ANOTHER ADVANCE ON
THE RIGHT HERE, WHICH COMES FROM
THE WORLD OF -- REALLY FROM
CHEMISTRY AND MACROMOLECULAR
CHEMISTRY.
AND HERE, THERE'S A GROUP OF
INVESTIGATORS THAT HAVE BEEN
ASSEMBLING MOLECULES AND COAXING
THEM INTO MAKING NANOMATERIALS.
YOU SEE A VARIETY OF THEM ON THE
SIDE HERE, INCLUDING, FOR
EXAMPLE, LIPID NANOMATERIALS
WHICH ARE, OF COURSE, HOW COVID
MRNA VACCINES ARE DELIVERED, AS
WELL AS SOME OTHER VERY FAMOUS
ONES, FOR EXAMPLE, BUT KEY
BALLS. BUCKY BALLS.
SO WE HAVE TWO DIFFERENT SETS OF
TECHNOLOGY THAT HAVE CONVERGED
OND A SCALE, WE THINK OF HUMAN
HARRAH'S ABOUT 100 MICRONS, AND. AS
INVENTORS INTERESTED IN HUMAN
HEALTH, IF YOU KIND OF SPLAY
THESE TECHNIQUES ACROSS A RULER,
THIS INDUSTRY HAS GIVEN US TOOLS
THAT ARROW US TO MA MANIPULATE
EVERYTHING FROM THE LINK SCALE
OF A RECEPTOR UP TO GROUPS OF
CELLS WHICH REALLY FORM
FUNCTIONAL UNITS IN OUR TISSUES
AROUND SORT OF HUNDREDS OF
MICRONS.
SO WHAT I'D LIKE TO TELL YOU
TODAY IS ABOUT TWO TISSUE MICRO
ENVIRONMENTS, THE LIVER
MICROENVIRONMENT AND TUMOR MICRO
ENVIRONMENTS.
AND HOW WE CAN CREATE TOOLS THAT
ALLOW US TO DISSECT THESE
MICROENVIRONMENT OR ASSEMBLE
THEM FOR THERAPEUTIC PURPOSES.
I'LL TELL YOU TWO STORIES ABOUT
THE LIVER, IN HONOR OF WIN, AND
ONE STORY ABOUT TEU TUMORS.
SO STARTING WITH HEPATIC MICRO
ENVIRONMENTS, THEN, JUST A
LITTLE ORIENTATION ON THE LIVER.
THIS IS AN IMAGE FROM A FAMOUS
ANATOMIST OF THE LIVER.
YOU CAN SEE IT HAS THIS GORGEOUS
MICRO ARCHITECTURE WITH MANY
INTERACTING CELL TYPES, AND THIS
GIVES RISE TO SOME 500
FUNCTIONS.
THE THE LIVER IS VITAL FOR LIFE.
PABLO NARUTA DESCRIBED IT AS THE
MODEST ORGANIZED UNDERGROUND
WORKER OF OUR BODY.
IT'S UNDERAPPRECIATED.
IT CAN DO REMARKABLE THINGS.
IT'S UNFORTUNATELY -- ITS
DYSFUNCTION TOUCHES 500 MILLION
PATIENTS WORLDWIDE, AND IT HAS
REMARKABLE CAPABILITIES WHERE IT
CAN REGENERATE UNDER CERTAIN
CIRCUMSTANCES.
SO IT'S JUST A FASCINATING
ORGAN.
I'VE STUDIED IT MOST OF MY
CAREER AND I KNOW WIN HAS
STUDIED IT MUCH LONGER THAN ME.
SO YOU THINK ABOUT WHAT CAN YOU
STUDY ABOUT THIS ARCHITECTURE OF
THIS ORGAN WITH THESE TOOLS.
SO I'M GOING TO START WITH AN
EXAMPLE OF WHAT ONE CAN STUDY BY
CREATING AN ARTIFICIAL HUMAN
MICROENVIRONMENT IN TWO
DIMENSIONS.
SO ON A FLAT SURFACE.
AND HERE WHAT WE DO IS WE
PATTERN SURFACES WITH LIGHT FROM
THE SEMICONDUCTOR TOOL INDUSTRY,
AND WE PATTERN BIOMOLECULES ON
THOSE SURFACES THAT WILL CONFER
THE ADHESION OF CELLS.
SO HERE YOU CAN SEE WORK FROM MY
COLLEAGUES WHERE YOU CAN PATTERN
A SINGLE CELL ON AN ISLAND OF
FIBRANECTIN OR A BOW TIE OF TWO
CELLS OR AN ASYMMETRIC
MULTICELLULAR ISLAND.
SO THESE TOOLS ARE VERY GENERIC,
WE CAN ESSENTIALLY PRECISELY
PLACE SELLS KRELS ON CELLS ON A SURFACE
AND STUDY THE ARCHITECTURE OF
THAT COMMUNITY.
JUST TO GIVE YOU A SENSE OF HOW
GENERIC THIS TOOL IS, THIS IS AN
IMAGE OF A SURFACE THAT HAD BEEN
PATTERNED WITH COLLAGEN TYPE
1 BY A FORMER POSTDOC OF MINE.
THIS IS ACTUALLY PART OF A
TRAVELING ART EXHIBIT AND WIN
HAS A COPY OF THIS ON HIS WALL
ACTUALLY.
THESE ARE RAD HEPATOCYTES
PATTERNED IN COLLABORATION WITH
AN ARTIST.
IF YOU ZOOM IN ON THESE, YOU CAN
SEE THESE STRUCTURES WHICH ARE
SPECIFIED BY LIGHT-BASED PA
PATTERNING OF COLLAGEN ARE
INCREDIBLY PRECISE AND REALLY
WHAT'S COMPOSED OF THEM IS RAD
HEPATOCYTES SPREAD ON THAT
SURFACE.
SO THESE ARE VERY GENERIC TOOLS.
SO I'D LIKE TO TELL YOU NOW WHAT
ONE COULD STUDY IN A
TWO-DIMENSIONAL SYSTEM LIKE
THIS.
IT MAY SURPRISE YOU THAT THIS
VIGNETTE IS GOING TO BE ACTUALLY
ABOUT A HUMAN PATHOGEN THAT WE
THINK OF AS A DISEASE OF THE
BLOOD.
THAT'S PLASMODIUM VIVAX.
AS I'LL SHOW YOU IN A MOMENT,
THIS ORGANISM HAS AN OBLIGATE
STAGE OF ITS LIFE CYCLE IN THE
LIVER, WHICH UNTIL VERY
RECENTLY, WE HAVE NOT KNOWN MUCH
ABOUT.
SO PLASMODIUM VIVAX REALLY
AFFECTS MANY PEOPLE GLOBALLY,
AND UNLIKE ITS COUSIN, IT TURNS
OUT TO BE A RELAPSING FORM OF
MALARIA, AND BECAUSE OF THAT,
IT'S QUITE DIFFICULT TO
ERADICATE.
SO LET ME SHOW YOU A LITTLE BIT
MORE ABOUT ITS LIFE CYCLE.
AND WHY THE LIVER PART OF IT IS
SO INTERESTING.
SO HERE IS A SPORE ZOITE COMING
FROM AN INFECTED MOSQUITO.
THAT WILL TRAVEL TO THE LIVER,
WHERE IT INFECTS HEPATOCYTES,
UNIQUELY.
IT WILL MULTIPLY OVER SEVEN TO
10 DAYS.
AND THEN BURST OUT OF THE LIVER,
WHERE IT WILL INFECT YOUNG RED
BLOOD CELLS, RETICULOCYTES, AND
THEN START THE PATTERN OF CYCLIC
FEVER THAT WE ASSOCIATE WITH
MALARIA.
NOW WHAT'S INTERESTING AND
SPECIAL ABOUT THE LIVER STAGE OF
THIS ORGANISM IS THAT THIS IS A
BOTTLENECK IN THE LIFE CYCLE, IF
YOU WILL.
SO WHEN YOU START OUT WITH
RELATIVELY FEW SPORE ZOITES AND
THE ORGANISM MULTIPLIES.
SO FROM A THERAPEUTIC
PERSPECTIVE, IF YOU COULD TARGET
IT IN THE LIVER, YOU WOULD
PREVENT SYMPTOMS, YOU WOULD
PREVENT TRANSMISSION, WHICH WILL
HAPPEN LATER IN THE BLOOD STAGE,
AND YOU WOULD PREVENT THIS
AMPLIFICATION OF BIOMASS OF THE
ORGANISM.
SO THERE'S BEEN A LOT OF
INTEREST IN TARGETING AT THIS
STAGE, AND THERE'S ONLY ONE DRUG
SO FAR THAT'S ABLE TO DO IT, AND
THAT'S A VERY OLD DRUG CALLED
PRIMOQUINN.
THE REASON THIS CAN RELAPSE EVEN
AFTER IT'S CLEARED IS BECAUSE OF
THIS GUY HERE.
THIS IS CALLED THE HYPNOZOITE
FOR HYPNOTIZE.
IT CAN STAY IN THE LIVER AS A
DORMANT -- IT STARTS TO MULTIPLY
AND IT CAN START THE WHOLE LIFE
CYCLE AGAIN.
SO THERE HAVE BEEN MANY GAPS IN
OUR UNDERSTANDING OF THIS LITTLE
ORGANISM.
WE DON'T KNOW ITS INCIDENCE
BECAUSE THERE ARE NO CLINICAL
BIOMARKER, WE DON'T KNOW ABOUT
HOW LONG IT CAN SURVIVE IN VIVO,
WE DON'T KNOW ABOUT THE
PERSISTENCE, WE DON'T KNOW WHAT
THE REACTIVATION QUEUES ARE, WE
DON'T KNOW WHAT DRUG TARGETS IT
EXPRESSES AND WHAT DRUGS IT
MIGHT BE SENSITIVE TO.
SO WE SET OUT TO DEVELOP AN IN
VITRO MODEL OF THIS ORGANISM IN
OUR TWO-DIMENSIONAL LIVERS THAT
I SHOWED YOU EARLIER.
SO THE MODEL SYSTEM THAT WE
DEVELOPED USING HUMAN
HEPATOCYTES LOOKS A LOT LIKE THE
PICTURE I SHOWED YOU EARLIER BUT
IT HAS ONE ADDITIONAL CELL TYPE.
AND SO HERE WHAT WE'VE DONE IS
PATTERN HUMAN HEPATOCYTES FROM
ORGAN DONORS ON COLLAGEN TYPE 1,
AND NOW WE SURROUND THEM WITH
FEEDER CELLS, WITH FIBROBLASTS
THAT SUPPORT THEIR PHENOTYPE.
AND USING THIS MANIPULATION,
WE'RE ABLE TO MAINTAIN THE HUMAN
HEPATOCYTE PHENOTYPE IN A
TWO-DIMENSIONAL CONSTRUCT IN THE
BOTTOM OF A WELL FOR ABOUT FOUR
TO SIX WEEKS.
DEPENDING ON THE DONOR.
AND WHAT'S INTERESTING AND WHAT
WIN AND I SPENT A LOT OF TIME
TALKING ABOUT OVER THE YEARS IS
THESE CELLS ACTUALLY POLARIZE IN
THIS CONFIGURATION.
EVEN THOUGH THEY'RE IN A
TWO-DIMENSIONAL MONO LAYER.
SO FOR EXAMPLE, IF YOU ADD A
FLOOR SEEN DAIS TATE INTO THIS
CULTURE, YOU CAN SEE THAT IT'S
TAKEN UP AND PUT OUT INTO THE
BIOCANULICULI JUST LIKE THEY DO
IN VIVO.
THEY ALSO EXPRESS DRUG
METABOLIZING ENZYMES AND THEY
HAVE LOTS OF UTILITY FOR MANY
APPLICATIONS IN ADDITION TO
STUDYING THE LIVER STAGE OF
PATHOGENS.
SO IN ORDER TO MAKE THIS USEFUL
TO THE BIOMEDICAL RESEARCH
COMMUNITY, WE MINIATURIZE THESE
MICRO PATTERNED CO-CULTURES IN A
WAY THAT WE COULD PUT THEM
INSIDE OF MULTIPLE PLATES.
SO WE'RE NO LONGER USING THE
EXACT TECHNIQUES OF THE
SEMICONDUCTOR INDUSTRY WHERE YOU
PATTERN A SURFACE WITH LIGHT.
INSTEAD HERE WE'RE BASICALLY
MAKING STAMPS AND THEN WE'RE
STAMPING INTO MULTI-WELL PLATES.
AND THAT'S ALLOWED US TO MAKE
DIFFERENT FORMATS OF THIS TOOL.
A 24-WELL VERSION, A 96-WELL
VERSION, AND A 384-WELL VERSION.
SO YOU CAN DO LOTS OF BIOLOGY
WITH VERY FEW HUMAN HEPATOCYTES.
OKAY.
SO NOW I WANTED TO DO THE
EXPERIMENT WITH VIVAX, AND I HAD
A VERY ADVENTUROUS GRADUATE
STUDENT AND THIS IS HOW HER
THESIS WENT.
SHE WOULD PATTERN THESE PLATES
IN BOSTON, WAIT FOR THE RAINY
SEASON IN THAILAND, WHERE VIVAX
IS ENDEMIC, FLY WITH THE CELLS
FROZEN AND THE PLATES TO OUR
COLLABORATOR LAB IN THAILAND,
WHERE THE LAB HAD COLLECTED
BLOOD FROM INFECTED VIVAX
PATIENTS IN THE FIELD AND FED
THOSE TO MOSQUITOES AND THEN
ISOLATED SPORE ZOITES FROM THOSE
MOSQUITOES THAT WE COULD PUT
INTO THE CULTURE.
SO WE WOULD THEN PUT THESE INTO
OUR MOO CROW PATTERN COCULTURES,
DO THE EXPERIMENT, TYPICALLY IT
LASTED 21 DAYS, TAKE SOME OF THE
PLATES AND FIX THEM, BRING THEM
BACK TO BOSTON TO THE BROAD
INSTITUTE, WHERE WE WOULD USE
MACHINE ALGORITHMS TO STUDY THE
PARASITES OVER THE COURSE OF
THEIR LIFE CYCLE, AND WITH THE
OTHER PLATE, WE WORKED WITH ALEX
SHALAK TO DO SINGLE CELL
SEQUENCING OF THE INFECTED
HEPATOSITES.
SO
HEPATOCYTES.
SO WE WOULD DISPERSE THOSE
CULTURES AND PUT THEM INTO A
FORMAT THAT ALEX HAS INVENTED
CALLED SEQ-WELL WHERE EVERY --
YOU CAN BARCODE THE RNA ON A
PER-WELL BASIS.
IF IT CONTAINED A HEPATOCYTE --
IF IT HAD BOTH THE HEPATOCYTE
AND A PATHOGEN, IT COULD CARRY
BOTH OF THEM ON THE SAME
BARCODE.
SO WHAT DID WE LEARN?
LET ME JUST SHOW YOU SOME
PICTURES OF THIS KIND OF ELUSIVE
PARASITE BECAUSE WE WERE SO
HAPPY TO HAVE GROWN IT AFTER 10
YEARS OF WORK ON WORKING ON IT.
SO WHAT YOU'RE LOOKING AT NOW IS
A CULTURE, AND THIS IS A
HISTOGRAM OF THE PARASITES
INSIDE THAT CULTURE.
AND HERE WE'RE STAINING THE
VACUOLE, SO THIS IS A MEMBRANE
THAT SURROUNDS A PARASITE INSIDE
THE HEPATOCYTE.
THIS IS THE HEPATOCYTE NUCLEI
WITH UIS4, AND WE'RE MARKING ITS
GENOME WITH THIS HISTONE
ACETYLATION MARKER.
YOU CAN SEE IN THE BEGINNING ALL
THE PARASITES ARE QUITE SMALL.
AS WE LET THESE GROW, LOOKING AT
DAY 8, WE SEE SOME OF THE SMALL
FORMS AND WE SEE SOME THAT HAVE
BEEN HIGHLY MULTINUCLEATED.
SO THESE HAVE REPLICATED.
IN PATIENT BIOPSIES, THE BIGGEST
ONE OF THESE THAT HAD BEEN NOTED
PREVIOUSLY WAS ABOUT 40 MICRONS.
IN OUR CULTURES, WE SEE THEM TO
BE UP TO 130 MICRONS.
YOU CAN SEE THEY JUST TAKE UP
THE WHOLE HEPATOCYTE CYTOPLASM.
THEN IF YOU WAIT A LITTLE
LONGER, ON DAY 10, THIS IS THE
FIRST TIME WE BELIEVE ANYONE HAD
EVER SEEN THIS IN VITRO, YOU CAN
SEE THE STRUCTURE BURSTING OUT,
AND THESE MARAZOITES COMING OUT
OF THE HEPATOCYTES, STREAMING
OUT
>>, AND THIS IS WHEN THEY WOULD
ENTER INTO THE BLOOD STAGE IN
THE BODY.
THIS IMAGE, I SHOULD SAY NEIL
WAS SO HAPPY TO SEE THIS, SHE
TOOK THIS IMAGE THROUGH THE
MICROSCOPE OBJECTIVE WITH HER
IPHONE BECAUSE WE HAVE NO VIDEO
MY
MICROSCOPY.
SO IF WE OVERLAY RETICULOCYTES,
YOUNG RED BLOOD CELLS ON TOP OF
THESE CULTURES, IN FACT, THEY
CAN COMPLETE THEIR FULL LIFE
CYCLE AND INFECT THE RED BLOOD
CELLS.
AND THEN IF WE LOOK AT WHAT'S
LEFT IN THE CULTURE AFTER
21 DAYS, ALL WE SEE ARE THESE
SMALL PERSISTENT FORMS, WHICH WE
THINK ARE HYPNOZOITES.
THERE ARE NO BIOMARKERS
DEFINITIVE FOR THEM, SO WE
WANTED TO SEE IF THEY REALLY
MIGHT CARRY ALL OF THE HALL
MARKS THAT ARE KNOWN CLINICALLY
TO DESCRIBE HYPNOZOITES, AND
THERE ARE FOUR OF THEM.
SO THE FIRST IS THAT THEY ARE
SMALL, QUIESCENT, MONO NUCLEATE,
AND PERSISTING.
WHICH WE FOUND.
THE SECOND IS THAT WHILE THEY DO
EXPRESS MARKERS LIKE UIS4, THEY
SHOULD NOT EXPRESS MATURE
MARKERS LIKE MARAZOITE SURFACE
PROTEIN, WHICH IS ON THE SURFACE
OF THESE REPLICATING FORMS THAT
ARE ABOUT TO COME OUT INTO THE
BLOOD, AND YOU SEE THEY ARE MSP1 NEGATIVE.
THE THIRD, AND THIS IS VERY
IMPORTANT, WE LEARNED THIS FROM
PATIENTS, IS THAT THESE
ORGANISMS SHOULD BE
DIFFERENTIALLY DRUG-SENSITIVE.
THAT IS THAT THEY SHOULD BE
SENSITIVE TO A DRUG LIKE
PRIAQUINE, AND YOU SEE THEY ARE,
BUT THEY SHOULD BE INSENSITIVE
TO A DRUG THAT ONLY KILLS
REPLICATING FORMS LIKE
ATOVAKWAN.
THE SMALL FORMS PERSIST.
THIS IS THE THIRD HALLMARK.
THE FOURTH HALLMARK SHOULD BE
THAT THE DORMANT FORMS ARE
CAPABLE OF REACTIVATING.
HERE WE GOT LUCKY, SOMETIMES IN
SCIENCE YOU GET LUCKY, WHICH IS
THAT IN SOME OF THE CULTURES, WE
WAITED, AND AFTER THEY WERE
CLEARED COMPLETELY OF THOSE
LARGE FORMS THAT BURST OUT ON
DAY 10, WE CAME BACK A WEEK OR
TWO LATER AND SAW THE DORMANT
NUMBER HAD DECREASED AND WE NOW
FOUND THESE LARGE REACTIVATED
FORMS.
SO WE HAVE ESSENTIALLY ALL FOUR
HALLMARKS OF HYPNOZOITES IN
VITRO THAT WE BELIEVE TO BE
CONSISTENT WITH CLINICAL DATA,
SO WE WERE BRAVE ENOUGH TO CALL
THIS A HYPNOZOITE WHEN WE
PUBLISHED OUR PAPER IN 2018.
NOW WE'VE SEEN IT MANY, MANY
TIMES, THERE'S LOTS TO STUDY
ABOUT IT, AND FOR THOSE OF YOU
WHO ARE INTERESTED IN NEW
EXCITING RESEARCH PROJECTS,
THESE ARE JUST SOME OF THE
THINGS THAT WE'VE BEEN DOING
WITH THIS MODEL SYSTEM AND
SHARING IT WITH THE COMMUNITY.
YOU CAN DO THE TRANSCRIPTIONAL
PROFILE OF THIS ORGANISM AND
I'LL SHOW YOU SOME OF THAT IN A
SECOND, YOU CAN STUDY THE
MECHANISMS OF DORMANCY AND
REACTIVATION, SEXUAL COMMITMENT
IN THE ORGANIZE ORGANISM, WHICH IS
THOUGHT TO HAPPEN IN THE BLOOD
STAGE.
NOW THAT WE HAVE THIS TOOL TO
STUDY THIS FORM IN VITRO,
THERE'S LOTS TO DO.
SO LET ME TELL YOU ONE OF THE
NEWER STORIES QUICKLY ABOUT THIS
ORGANISM THAT'S ABOUT TO BE
PUBLISHED THAT HAS TO DO WITH
THIS DUAL SEQUENCING.
SO I DESCRIBED THIS TO YOU
EARLIER, WHERE WE DISPERSED THE
CULTURE INTO SINGLE WELLS AND
EVERY WELL IS BARCODED.
AND WHAT WE DID WHEN WE DID THIS
EXPERIMENT WAS WE FOUND 1400
PARASITE GENOMES AND 33,000
HEPATOCYTES.
SOME WERE INFECTED, SOME WERE
UNINFECTED.
WE COULD TELL WHICH WERE
UNINFECTED BECAUSE THEY HAD THE
SAME BARCODE.
THESE ARE SOME OF THE THINGS
THAT WE'VE LEARNED IN THIS
STUDY.
SO ONE OF THEM IS THAT WE COULD
SEE THE PARASITE MATURING OVER
THE FIRST TWO WEEKS OF LIFE.
SO WHAT WE DID WAS WE TOOK THE
TRANSCRIPTOME THAT WE PREVIOUSLY
HAD DONE IN THE INITIAL
EXPERIMENT AND CREATED A 10-GENE
SIGNATURE FOR THE HYPNOZOITE,
THE DORMANT FORM, BASED OFF OF
THE ORIGINAL DATA.
AND THEN WE APPLIED IT TO THE
SINGLE CELL DATA.
AND THERE'S SOME VERY
INTERESTING GENES HERE.
ONE OF THEM IS A TRANSLATIONAL
REPRE SER, WHICH SEEMS TO BE
IMPORTANT FOR QUIESCENCE.
TWO OF THEM ARE ACTUALLY
PROTEASES, AND THERE'S SOME
SUGGESTION THAT PROTEOLYSIS OF
HOST PROTEINS IS IMPORTANT FOR
THE PARASITE TO PERSIST.
AND THEN ONE OF THEM IS ACTUALLY
MDR2, WHICH MAKES ONE WONDER
ABOUT RESISTANCE TO DRUGS.
SO THIS IS A SIGNATURE FOR THE
HYPNOZOITE.
AND NOW, WHEN YOU FOLLOW THE
PARASITE AROUND ITS LIFE CYCLE
OVER TIME IN THE LIVER, YOU SEE
THAT THE DAY ONE FORMS CLUSTER
TOGETHER.
THESE ARE THOSE SPORE ZOITES
THAT CAME OUT OF THE MOSQUITO
INTO THE LIVER.
THE MIDDLE FORMS HAVE TWO
CLUSTERS, AND THIS CLUSTER HERE
CARRIES ALL THOSE HYPNOZOITE
GENES, AND AS THEY MATURE,
THERE'S A FORM THAT'S STILL IN
HEPATOCYTES HERE AND THIS THAT'S
BURST OUT.
SO YOU CAN ANNOTATE THESE AS WE
GO.
WHAT'S REALLY INTERESTING ABOUT
THIS, AND I'LL SHOW YOU AT THE
END, IS THAT YOU CAN EVEN ASK
WHETHER ANY OF THESE HAVE
COMMITTED ALONG THE SEXUAL
DIFFERENTIATION PATH, WHICH
AGAIN WAS THOUGHT TO OCCUR ONLY
IN THE BLOOD STAGE.
SO WE'RE STARTING TO GET A SENSE
FOR THE LIFE CYCLE OF THIS
ORGANISM, AND THIS IS JUST THE
PARASITE.
THEN YOU MIGHT ASK, HOW IS THE
HEPATOCYTE RESPONDING TO THIS
INFECTION?
SO HERE NOW, THESE ARE THE
33,000 HEPATOCYTES.
YOU CAN SEE HOW THEY CLUSTER
LARGELY TOGETHER.
WE HAVE EIGHT DIFFERENT SUBTYPES
IN THIS SAMPLE.
WHAT'S INTERESTING TO ASK HERE
IS, WHICH CELLS ARE INFECTED?
SO IF YOU LOOK IN THESE EIGHT
DIFFERENT CLUSTERS, WHICH ARE
INFECTED, YOU SEE ACTUALLY ALL
THE CLUSTERS CARRY INFECTION.
SO THERE'S NO PREDOMINANT
HEPATOCELLULAR PHENOTYPE THAT'S
MORE PERMISSIVE.
THE ONLY THING THAT ABOUT 60% OF
THESE SHARES SOLD HAD IN COMMON WAS
SRD1, AND WE CONFIRMED THAT IN
OUR DATA AND VALIDATED THAT
RESULT.
SO THE ONE THING THAT CAME UP IN
IN MANY OF THE CULTURES WERE
INTERFERON PATHWAY-RELATED
GENES, OR SO CALLED ISG OR
INTERFERON STRESS GENES.
SO HERE YOU CAN SEE TWO OF THEM,
IFI6 AND IFI-T1, AND THEY'RE
SORT OF SCATTERED AMONG THE
NAIVE HEPATOCYTES AND THOSE THAT
HAVE JUST BEEN EXPOSED WITH
MALARIA SALIVARY GLAND MATERIAL.
THAT'S CALLED A MOCK EXPOSURE.
YOU CAN SEE WHEN YOU EXPOSE A
CULTURE TO VIVAX ITSELF, THAT
MANY OF THE HEPATOCYTES LIGHT UP
WITH THESE ISGs.
NOT JUST THE INFECTED
HEPATOCYTES, AND, IN FACT, THE
INFECTED HEPATOCYTES, THE
PARASITE SEEMS TO SUPPRESS THE
RESPONSE TO INFECTION, BUT THE
BYSTANDER HEPATOCYTES ACTUALLY
UPREGULATE ALL OF THESE
INTERFERON RESPONSES.
SO THIS IS A LOT OF DATA, IT'S
ABOUT TO COME OUT.
I JUST WANTED TO GIVE YOU A
SNIPPET AND TO SUMMARIZE THE TWO
THINS THAT WE'RE LEARNING AND
THE CONVERSATION BETWEEN THE
HOST AND THE PARASITE THAT THIS
SYSTEM, I HOPE, WILL ALLOW US TO
UNWIND.
AS ON THE HEPATOCYTE SIDE, THE
INFECTED HEPATOSIDE DOWN
REGULATES THE INTERFERON
RESPONSE.
AND THE BYSTANDER HEPATOCYTES
UPREGULATE THE RESPONSE.
BASED ON SOME OTHER DATA THAT
HEPATOCYTES ACTUALLY MEDIATED BY
GAP JUNCTIONS.
THIS IS SOMETHING SIMILAR THAT
CHARLIE RICE AND I SAW WHEN
LOOKING AT HEPATITIS C, SO
THERE'S SOMETHING VERY
INTERESTING HAPPENING HERE JUST
ON THE HOST RESPONSE SIDE.
IF YOU ADD INTERFERON GAMMA INTO
THIS CULTURE, YOU ACTUALLY CAN
USE TO CLEAR HYPNOZOITES.
ON THE PARASITE SIDE, I
MENTIONED TO YOU THAT THERE ARE
THESE VARIOUS SUBSTRUCTURES IN
THE DATA, ZOITES ARE HERE.
IF YOU ACTUALLY LOOK, WE'VE
FOUND A MASTER REGULATOR SEXUAL
DIFFERENTIATION CALLED AP2G,
THOUGHT TO ONLY BE UPREGULATED
IN THE BLOOD STATE YOUR NAME.
WE STAGE.
WE FOUND IT HERE IN THE LIVER
FROM THE VERY BEGINNING, FROM
DAY ONE.
WE SEE THAT SOME OF THE
HYPNOZOITES ACTUALLY CARRY THIS
AND SOME OF THE REPLICATED
FORMS.
AND THIS IS ACTUALLY REALLY
INTARIQING BECAUSE THERE ARE
SOME DATA IN THE MALARIA
COMMUNITY IN CHALLENGE
EXPERIMENTS WHERE PATIENTS HAVE
SHOWN THE ABILITY TO BE
TRANSMISSIBLE AT DAY 9 AFTER
INFECTION.
WHICH EVERYONE ALWAYS THOUGHT
WAS WAY TOO EARLY, BECAUSE
THEY'RE SUPPOSED TO COME OUT OF
THE LIVER AT DAY 10 AND THEN GO
INTO THE BLOOD STAGE AND THEN
UNDERGO SEXUAL DIFFERENTIATION
BEFORE YOU COULD BE TRANS
MISSABLE.
THESE DATA SUGGEST IT'S
DEVIATING SEXUALLY EVEN IN THE
LIVER STAGE.
SO FROM A TRANSLATIONAL
PERSPECTIVE, IT MAY SUGGEST THAT
SOME OF THE DRUGS THAT ARE BEING
DEVELOPED AGAINST THE SEXUAL
STAGES OF THE ORGANISM MIGHT
ACTUALLY BE USEFUL FOR TARGETING
THE LIVER STAGE.
OKAY.
SO THIS IS MY FIRST VIGNETTE.
IT'S AN EXAMPLE OF WHAT A 2D
MICROENVIRONMENT OF HUMAN
HEPATOCYTES IN VITRO MIGHT ALLOW
YOU TO DO FOR INFECTIOUS
DISEASE.
THE LAST THING I'D LIKE TO
MENTION FROM A TOOL PERSPECTIVE
IS THAT THE DEVELOPMENT OF TOOLS
CAN REALLY OPEN UP NEW DOORS.
SO WE STARTED THIS IN 2008, AND
IN THE BEGINNING, WE WORKED ON
HEPATITIS C AND HEPATITIS B WITH
CHARLIE RICE.
AND THEN VALCIPRIN AND VIVAX,
AND THIS TOOL HAS BEEN USINGED
BY A VARIETY OF LABS REALLY
AROUND THE WORLD, AS I MENTIONED
TO STUDY MANY, MANY TOPICS,
INCLUDING VACCINES, AND WE'RE
NOW JUST GETTING TO THE NOVEL
THERAPEUTIC ACTIVITY, THINGS
LIKE RNA INTERFERENCE AND
CRISPR, AND GENE DELIVERY.
SO THIS VERY SIMPLE TOOL, I
THINK ACTUALLY HAS A LOT TO
OFFER.
SO THAT'S MY FIRST VIGNETTE.
THE SECOND ONE I'D LIKE TO
MENTION IS ABOUT
THREE-DIMENSIONAL HEPATIC MICRO
ENVIRONMENTS.
SO I SHOWED YOU BEFORE THAT
SEMICONDUCTOR TOOLS ALLOWED US
TO WRITE ON SURFACES.
THOSE SAME TOOLS CAN BE USED TO
MOLD AND TEMPLATE AND PRINT
THREE-DIMENSIONAL MATERIALS.
SO WHAT YOU SEE HERE ARE SOME
IMAGES OF A VARIETY OF DIFFERENT
STRUCTURES MADE USING MICRO
FABRICATION TOOLS BUT IN THREE
DIMENSIONAL FORMS.
FOR EXAMPLE, THIS IS A MICRO
FLUIDIC STRUCTURE THAT'S MAKING
LITTLE HEPATIC 3D MICRO TISSUES.
SO WHAT I'D LIKE TO DO IS TELL
YOU A STORY ABOUT 3D MICRO
ENVIRONMENTS IN THE CONTEXT OF
ANOTHER REALLY FASCINATING
MEDICAL CHALLENGE, WHICH IS
LIVER REGENERATION.
SO JUST TO KIND OF ORIENT YOU
HERE, THIS IS A STORY WHICH AS
FAR AS I KNOW START IN 1930s,
ALTHOUGH WIN MAY KNOW AN OLDER
STORY, WHERE ONE CAN DO A
PARTIAL HEPATECTOMY IN WHICH THE
LIVER REGENERATES WITHIN WEEKS.
THERE'S MANY FASCINATING THINGS
ABOUT THIS, BUT ONE THAT'S
ALWAYS FASCINATED OUR WORK HAS
BEEN THE WORK OF NANCY BOOKER,
WHICH DATES BACK TO THE 1950s.
A PARABIOSIS EXPERIMENT, WHERE
THE CIRCULATION OF TWO ANIMALS
WAS CONNECTED AND A PARTIAL HELP
TECT MEE WAS DONE IN THE ONE AND
THE OTHER LIVER COULD ACTUALLY
RESPOND TO THAT INJURY.
THAT SUGGESTED IN PART THAT THE
SIGNALS INVOLVED WITH HEPATIC
REGENERATION MUST BE BLOODBORNE
OVER THE YEARS, GEORGE AND MANY
OTHERS HAVE DUG INTO THIS, AND
WHAT THEY'VE FOUND IS THAT IN
PART, THE QUEUES IN HEPATIC
REGENERATION ARE A CONVERSATION
BETWEEN HEPATOCYTES IN THE LIVER
AND THEIR NEIGHBORING CELLS, THE
SINUSOIDAL AND EPITHELIAL CELLS.
I'M KIND OF BLOWN UP WHERE YOU
SEE THAT CONVERSATION HERE WHERE
YOU SEE EPITHELIAL CELLS AND
HEPATOCYTES, PART RESPOND TO
INJURY, PART RESPOND TO FLUID
FLOW, THESE CELLS START
PRODUCING PARAFFIN FACTORS, SO
FOR COMPACT, ENDOTHELIAL CELLS
MAKE THINGS, AND THE HEPATOCYTES
IN TURN MAKE GROWTH FACTORS.
AND THAT ALLOWS THE HEPATOCYTES
AND THE ENT THEEL YELL CELLS TO
COORDINATE THEIR REPLICATION AS
THE LIVER REGROWS.
SO WE WANTED TO STUDY THE HUMAN
ANALOG OF THIS.
IT HAD BEEN REALLY WELL STUDIED
IN RODENTS AND NOT WELL STUDIED
IN HUMANS, SO WE WANTED TO SEE
IF WE COULD MAKE A PATTERN OF
INTERACTIONS AS THEY RELATE TO
REGENERATION USING SOME OF THESE
PD TOOLS.
SO THIS IS HOW WE DID IT.
THE FIRST STEP WAS TO TAKE HUMAN
HEPATOCYTES AND MAKE SPHEROIDS
OUT OF THEM.
WE DO THIS USING A MICRO FABL
KATEED MOLDS, THEY FORM THESE
AGGREGATES OF ABOUT 150 MICRONS
IN DIAMETER.
IN THIS STRUCTURE, THEY'RE
STABLE IN CULTURE FOR WEEKS.
THE FULL PHENOTYPE THAT I
DESCRIBED.
AND THEN WE WANTED TO PUT THEM
CLOSE IN TRACKS WITH ENDOTHELIAL
CELLS, AND IN ORDER TO DO THIS
WORK, WE WORKED WITH MY
COLLEAGUE, CHRIS CHEN AND BOSTON
UNIVERSITY, WHO'S AN EXPERT IN
VASCULAR BIOENGINEERING.
WHAT CHRIS AND HIS LAB HAD DONE,
AND AS YOU SEE HERE, IS TAKEN
ENDOTHELIAL CELLS, HUMAN VEIN
ENDOTHELIAL CELLS, SO THEY'RE
NOT SIGN SOY DAL ENDOTHELIAL
CELLS BUT THEY ARE HUMAN CELLS,
AND PUT THEM IN A CHANNEL, MICRO
FABRICATED CHANNEL INSIDE A
HYDROGEL.
SO THIS IS A FIBRIN HYDROGEL.
YOU CAN SEE THEY FORM THESE
LOVELY JUNCTIONS THAT YOU COULD
PUT FLOW THROUGH THIS CHANNEL,
AND KRILS AND HIS LAB HAVE USED
THIS TO STUDY ANGIOGENIC
SPROUTING AND ANY NUMBER OF
VASCULAR QUESTIONS.
SO WE WANTED TO PUT THESE TWO
SYSTEMS TOGETHER AND GET THE
HEPATOCYTES TO TALK TO THE
ENDOTHELIAL CELLS AND SEE IF WE
COULD STUDY LIVER REGENERATION.
SO WE MADE A LITTLE CHIP, WE
CALLED IT SHEER, WHERE THERE'S A
PANEL IN THE MIDDLE THAT HAS THE
HUMAN ENDOTHELIAL CELLS AND THE
SPHEROIDS AROUND THEM AND ASK
HOW THEY RESPONDED TO VARIOUS
STIMULI.
AND TO TAKE THIS CONVERSATION
THAT WE WERE INTERROGATING
BEFORE AND SEE WHETHER WE COULD
LEARN ANYTHING NEW ABOUT IT IN A
HUMAN CONTEXT.
SO WE DID THESE EXPERIMENTS, WE
CAN ADD THINGS LIKE FLOW, YOU
CAN SEE THAT THE CELLS THEN WILL
PRODUCE A VARIETY OF DIFFERENT
FACTORS IN THE PRESENCE OF FLOW
BECAUSE THE ENDOTHELIAL CELLS
ARE TOO SENSITIVE TO SHARE, THEN
WE COULD ADD INFLAMMATORY
CYTOKINES LIKE THOSE THAT YOU
MIGHT SEE IN INJURY, LIKE IL-1
BETA.
NOW YOU SEE A WHOLE BUNCH OF
FACTORS COMING UP IN THE MEDIA,
AND ONE THING THAT WE WERE
REALLY INTRIGUED BY WAS THIS
ONE, PROSTAGLANDIN E2.
OUR COLLEAGUE HAD PREVIOUSLY
REPORTED THAT THIS WAS INVOLVED
ACTUALLY IN ZEBRAFISH LIVER
REGENERATION.
SO WE'RE VERY INTERESTED TO SEE
IT HERE.
SO THE QUESTION BECAME FOR US,
WHO IS MAKING THE PGE2 IN THIS
SYSTEM, AND HOW IS IT WORKING IN
THIS SORT OF CONVERSATION
BETWEEN HEPATOCYTES AND
ENDOTHELIAL CELLS?
SO RE WE PUT A CELL CYCLE REPORTER
AND LOOKED AT CYCLING
HEPATOCYTES IN RESPONSE TO THESE
SIGNALS, AND WE COULD SEE THAT
IN THE PRESENCE OF IL-1 BETA, WE
SAW THEM ENTERING THE CELL
CYCLE, AND IN THE PRESENCE OF
ENTERING THE CYCLE.
SO THE QUESTION WE HAD WAS,
WHETHER THIS PROSTAGLANDIN E IT
WAS
E2 WAS BEING PRODUCED BY THE
ENDOTHELIAL CELLS AND ACTUALLY
MEDIATING THIS ENTRY INTO THE
CELL CYCLE.
SO BECAUSE WE'RE IN AN IN VITRO
SYSTEM, WE CAN JUST MANIPULATE
THE CELLS GENETICALLY
INDIVIDUALLY, SO WE DID THAT.
WE TOOK THE ENDOTHELIAL CELLS,
WE USED CRISPR, WE MAPPED OUT
PGE SYNTHASE WHICH ALLOWS US TO
PRODUCE PGE2 IN THE ENDOTHELIAL
CELLS AND DID THE SAME
EXPERIMENT AND ASKED WHAT
HAPPENS, AND SO WHAT YOU SEE IS,
HERE'S A CONTROL EXPERIMENT, SO
NOW IN THE PRESENCE OF IL-1
BETA, THE CELLS ARE CYCLING.
AND NOW IN THE PRESENCE OF IL-1
BETA, WITH THE ABSENCE OF PGE IN
ENDOTHELIAL CELLS, THE CELLS NO
LONGER CYCLE.
SO ALL OF THE IL-1 BETA INDUCED
CYCLING IN THIS SYSTEM SEEM TO
BE DEPENDENT ON PGE2 FROM THE
ENDOTHELIAL CELLS.
SO THIS ALLOWS US NOW TO HAVE A
WORKING MODEL WHERE WE THINK
THAT THE ENDOTHELIAL CELLS IN
HUMAN LIVER REGENERATION ARE
MAKING PGE2 AND CONTRIBUTING TO
HEPATOCYTE CELL CYCLE ENTRY.
THE TRANSLATIONAL IMPLICATIONS
ARE VERY INTERESTING BECAUSE OF
COURSE THE PROSTAGLANDINS HAVE A
SET OF GPCR RESPEP RECEPTORS AND
TARGETING THEM COULD ACTUALLY
PRODUCE HEPATOCYTE PROLIFERATION
THERAPEUTICALLY, SO THAT'S THE
IMPLICATION OF THIS WORK.
SO THAT WAS IN VITRO EXPERIMENT.
WE WANTED TO GO BACK THEN AND
ASK HOW THIS WORKS RELATES TO
WHAT NANCY BOOKER SAW IN VIVO.
SO HOW WOULD THESE TYPES OF
CONSTRUCTS REACT TO A REAL IN
VIVO LIVER INJURY.
AND IN ORDER TO DO THAT, WE MADE
AN IMPLANTABLE VERSION OF THESE
CHIPS.
SO NOW WE HAVE A MULTICHANNEL
SYSTEM, AND WE SURROUND THOSE
MULTIPLE CHANNELS WITH THE
HEPATOCYTE SPHEROIDS, AND WE
EMBED THE WHOLE THING IN FIBRIN,
WHICH IS A HYDROGEL, AND WE CAN
MAKE IMPLANTABLE STRUCTURES THAT
LOOK LIKE THIS IN THE MICROSCOPE
AND LOOK LIKE THIS ON THE TIP OF
YOUR GLOVE.
SO THIS IS ABOUT A 1 CENTIMETER
IMPLANT.
AND WE PUT THEM IN THE
INTRAPERITONEAL SPACE OF A
MOUSE, WHERE WE CAN MANIPULATE
THE LIVER AND ASK HOW THESE
GRAPHS RESPOND.
SO HERE YOU CAN SEE THE
EXPERIMENT.
THESE GRAPHS NOW CARRY A
REPORTER FOR HEPATOCYTE HEALTH,
SO THIS IS DRIVEN BY THE ALBUMEN
GENE, AND IT'S LUCIFERASE.
SO ESSENTIALLY WHAT YOU SEE IS
THAT THE GRAPHS WILL ENGRAFT IN
THE PERITONEAL SPACE BY
RECRUITING VASCULATURE, AND THAT
RECRUITMENT OF VASCULATURE IS
REALLY DEPENDENT ON THE
ENDOTHELIAL CELLS IN OUR
CONSTRUCT.
AND THEY PERSIST FOR ABOUT 90
DAYS IN THESE ANIMALS, WHICH IS
PLENTY OF TIME TO DO SORT OF A
SURGICAL OR CHEMICAL INJURY TO
THE LIVER.
SO WHEN WE DO THAT SAME
EXPERIMENT, THE PARTIAL
HEPATECTOMY TO THE MOUSE LIVER
AND ASK WHAT HAPPENS TO THIS
GRAFT IN THE PERITONEAL SPACE,
WHAT WE SEE IS THAT THE
HEPATOCYTES, A FEW PERCENT OF
THEM, ABOUT 5% OF THEM, ENTER
INTO CELL CYCLE.
WE SEE THAT BY USING AN ANALOG
WE GIVE THE ANIMALS, AND YOU CAN
SEE THIS IN THE HEPATOCYTES.
SO THIS IS VERY INTERESTING, BUT
IT WAS A TRANSIENT EFFECT,
BECAUSE WHEN THE MOUSE LIVER
REGROWS, THE REGENERATIVE
STIMULUS WENT AWAY.
SO WE WANTED TO ASK WHETHER WE
COULD GET THESE ECTOPIC LIVERS,
IF YOU WILL, TO PROLIFERATE EVEN
FURTHER BY CREATING A SUSTAINED
INJURY SIGNAL IP IN VIVO.
WE DID THAT USING THE SO CALLED
FAH MOUSE, WHICH IS A MOUSE
MODEL OF A HUMAN DISEASE.
IT'S A TYROSINEMIA.
THIS HAS BEEN POPULARIZED BY THE
GROUP.
AND IF YOU FEED THE MOUSE A
PROTECTIVE DRUG, NTBC, THE
ANIMALS ARE FINE.
IF YOU TAKE THEM OFF THE DRUG,
THEY DEVELOP TOXIC LEVELS OF
TYROSINE, WHICH IS A LIVER
INJURY, AND YOU CAN CONTINUE
THAT PROCESS WHICH WILL MAINTAIN
A STEADY STATE OF LIVER INJURY.
SO WE ASK WHAT WOULD THE
RESPONSE OF OUR HUMAN GRAFTS TO
THIS CHRONIC LIVER INJURY BE,
AND WHAT YOU SEE HERE IS YOU
ESSENTIALLY EXPAND PRETTY
DRAMATICALLY, SO ABOUT 50 FOLD.
SO HERE ON THE LEFT, YOU'RE
LOOKING AT HEPATOCYTES STAINED
FOR ARNLG ARGENASE, YOU CAN SEE THE
HEPATOCYTES HAVE EXPANDED.
INTERESTINGLY, REORGANIZED.
IF YOU LOOK NE BLOOD OF THOSE
ANIMALS, YOU CAN TRACK HUMAN
ALBUMIN AT ABOUT A 50 FOLD
INCREASE.
SO WE'VE BEEN REALLY INTERESTED
IN THIS SORT OF CONCEPT NA A CONCEPT -- WE 'VE
STARTED TO THINK ABOUT WHETHER
THIS MIGHT BE THERAPEUTICALLY
USEFUL.
SO JUST TO SORT OF WALK YOU
THROUGH OUR THINKING, ESPECIALLY
FOR DISEASES, FOR EXAMPLE,
SINGLE GENE DEFECTS THAT DON'T
REQUIRE MUCH ENZYME TO BE
THERAPEUTICALLY IMPORTANT, EVEN
TODAY WHAT WE DO IS WHOLE ORGAN
TRANSPLANTATION.
SO YOU TAKE THE UREA CYCLE
DISORDERS, THOSE PEDIATRIC
PATIENTS ARE TRANSPLANTED WITH
LIVERS.
SO IT'S REALLY A WHOLE
REPLACEMENT APPROACH.
SO THE FIELD HAS BEEN INTERESTED
IN A LONG TIME WHETHER WE COULD
ACTUALLY JUST INFUSE HEPATOCYTES
THEMSELVES WITHOUT REMOVING THE
LIVER AND REPLACING IT
COMPLETELY, AND THESE
EXPERIMENTS, THERE'VE BEEN ABOUT
100 CASE STUDIES IN PATIENTS
THAT HAVE LARGELY BEEN
DISAPPOINTING, THAT WE'VE
LEARNED A LOT FROM THIS FIELD,
BUT INJECTING CELLS INTO THE
LIVER HAS A VARIETY OF
CHALLENGES.
ONE OF THEM IS THAT THEY DON'T
ENGRAFT EFFICIENTLY.
SO WE LOSE 90-PLUS PERCENTAGE OF
THOSE HEPATOCYTES ALONG THE WAY.
SO OUR THINKING HAS BEEN TO
BUILD OFF OF OUR PRE-CLINICAL
DATA.
PERHAPS WE CAN JUST LEAVE THE
LIVER IN PLACE AND ADD A
PERITONEAL GRAFT OF HUMAN
HEPATOCYTES THAT HAVE BEEN ENG
FEARED TO BE IMPLANTED AND
RECRUIT VASCULATURE AND SUPPORT
THE PATIENT, KIND OF LIKE A
BOOSTER.
SO WE ARE ACTUALLY -- WE HAVE A
STARTUP COMMITTEE I MENTIONED
EARLIER THAT IS ATTEMPTING TO DO
THAT, WHICH WE'LL BE FILING AN
IND FOR FIRST PATIENT TRIALS, WE
HOPE IN ABOUT A YEAR.
SO WHAT I'VE TOLD YOU ABOUT THE
LIVER IS THAT WE CAN STUDY IT IN
TWO DIMENSIONS, AND THAT CAN
ENABLE THE INVESTIGATION OF
HUMAN PATHOGENS LIKE P. VIVAX.
WE CAN STUDY IT IN THREE
DIMENSIONS, FOR EXAMPLE, WE CAN
STUDY REGENERATION THAT'S
PATHWAYS THAT ARE SPECIFIC TO
THE HUMAN.
AND THAT WE ARE STARTING TO
THINK ABOUT WAYS TO TRANSLATE
SOME OF THESE THINGS TO
PATIENTS, AND THIS IS JUST AN
IMAGE OF A GRAFT THAT WE'RE
WORKING ON THE MANUFACTURING OF
THESE TO SCALE THEM UP.
SO MY LAST VIGNETTE, I WANT TO
TELL YOU A LITTLE BIT ABOUT
DISREGULATED TISSUE ENVIRONMENT
LIKE THE TUMOR MICROENVIRONMENT.
AND NOT REALLY BUILDING IT UP SO
MUCH WITH TOOLS LIKE ON A
TWO-DIMENSIONAL PATTERN OR
THREE-DIMENSIONAL PATTERN, BUT
INSTEAD MAKING MATERIALS THAT
ARE SO SMALL THAT THEY CAN
ACTUALLY ENTER INTO THAT TISSUE
MICROENVIRONMENT AND MAKE
MEASUREMENTS THAT WOULD INFORM
US SCIENTISTS.
SO HERE WHAT WE'VE DONE IS MAKE
NANOMATERIALS THAT CAN ENTER
INTO THE TUMOR MICROENVIRONMENT
TO QUERY IT.
SO TO SORT OF SET THE STAGE FOR
THIS WORK, AND I KNOW I'M
RUNNING SHORT ON TIME SO I WON'T
BE AS LONG WITH THIS EXAMPLE,
WE'VE BEEN REALLY INTERESTED IN
OFFERING PHYSICIANS TOOLS TO
MAKE INFORMED DECISIONS ABOUT
PATIENT CARE.
SO IF YOU JUST SORT OF THINK
ABOUT THE LANDSCAPE OF CANCER
CARE, YOU NEED TO ASSESS RISK,
DETECT EARLY, MAKE A DIAGNOSIS,
ASSESS TREATMENT RESPONSE, AND
THEN MONITOR FOR SURVEILLANCE.
SO THERE'S OBVIOUSLY MANY, MANY
POINTS ALONG A PATIENT JOURNEY
THAT WE NEED BETTER INFORMATION.
AND IN PARTICULAR, WITH REGARD
TO OUTCOMES, WE KNOW THAT EARLY
DETECTION ACROSS A WIDE VARIETY
OF TUMORS LEADS TO BETTER
OUTCOMES, SO THIS HAS BEEN A
REAL AREA OF INTEREST FOR THE
FIELD.
HISTORICALLY WE HAVE SCREENED
THINGS LIKE MAMMOGRAMS AND
COLONOSCOPY, PRETTY HIGH
INFRASTRUCTURE APPROACHES.
SO THERE'S A FIELD EMERGING THAT
YOU MAY WELL KNOW ABOUT, WHICH
IS CALLED LIQUID BIOPSY, AND IN
THIS FIELD, WHAT'S BEEN
INTERESTING HAS BEEN TO TAKE A
BLOOD SAMPLE AND TO TRY AND
ESSENTIALLY -- TO LOOK AT SHED
PRODUCTS OF CANCER IN THE
CIRCULATION, FOR EXAMPLE,
CELL-FREE NUCLEIC ACIDS.
WHILE THIS IS A VERY EXCITING
FIELD, IT HAS MANY LIMITATIONS
SO FAR AND IN PARTICULAR, IT'S
VERY HARD TO DETECT TO DETECT
TUMORS EARLY, WHEN THEY'RE
SMALL.
SO WE CAN AMPLIFY THOSE SIGNALS
BY USING SOME OF THESE
NANOMATERIAL APPROACHES.
SO I'LL SHOW YOU WHAT I MEAN.
IN PARTICULAR, WE'RE INTERESTED
IN USING A CLASS OF ENZYMES THAT
ARE KNOWN TO BE CANCER
DISREGULATED AND THOSE ARE
CALLED THE PROTEASES.
SO THERE'S ABOUT 500 OF THEM IN
THE HUMAN GENOME AND THERE ARE
FIVE MAJOR CLASSES, AND THESE
HAVE BEEN ASSOCIATED WITH REALLY
ALL THE CANCER HALLMARKS.
SO THEY'RE KNOWN TO BE
DISREGULATED WITH CANCER TUMOR
INITIATION, SURVIVAL,
ANGIOGENESIS INNOVATION AND THE
IMMUNE SYSTEM.
AND REALLY MOST FAMOUSLY, I
THINK, MMP9 IS THE POSTER CHILD
FOR THIS FIELD AS ONE THAT IS
INVOLVED WITH THIS ANGIOGENIC
SWITCH.
SO DESPITE THEIR INVOLVEMENT
WITH TUMOR PATHOGENESIS, THEY'VE
BEEN REALLY DIFFICULT TO STUDY.
THEY'RE EXPRESSED IN PRO FORMS,
THEY'RE TYPICALLY ACTIVE
LOCALLY, AND THEY ACTUALLY CAN
EXIST WITH LOCAL INHIBITORS.
SO WE'RE REALLY INTERESTED TO
SEE WHETHER WE COULD MAKE SOME
SORT OF MULTIPLEX TOOL TO
PROFILE THEIR ACTIVITY IN TUMORS
IN A WAY THAT COULD BE AMPLIFIED
AND GIVE US A WINDOW INTO TUMOR
BIOLOGY.
SO WE DID THAT BY INVENTING A
CLASS OF MATERIALS THAT ARE WHAT
WE CALL ACTIVITY-BASED SENSORS.
SO HERE WHAT YOU'RE LOOKING AT
IS A SOLID TUMOR SURROUNDING A
BLOOD VESSEL.
IN THIS BLOOD VESSEL, WE'RE
DELIVERING NANOMATERIALS THAT
ARE ABOUT 100 NANOMETERS IN
SIZE, AND THEY ARE EXTRAVASATING
FROM THE VESSEL, SO THEY'RE
LEAKING OUT OF THAT VESSEL.
AND THEY ARE DESIGNED TO BE
ACTIVATED BY PROTEASES THAT ARE
IN THE TUMOR MICROENVIRONMENT.
SO FOR EXAMPLE, MMP9, WHICH IS A
PROTEASE WHICH CAN CATALYZE THE
CLEAVAGE OF A PEPTIDE.
SO ONE COPY OF THE PROTEASE
COULD LIBERATE MANY, MANY
PEPTIDES FROM A NANOMATERIAL.
AND WE DESIGN THESE PEPTIDES SO
THAT THEY ARE RESISTANT TO
DEGRADATION IN THE BLOODSTREAM,
WE DO THAT BY MAKING THEM OUT OF
D AMINO ACIDS, AND THEN WE
DESIGN THEM SO THAT THEY CAN BE
CONCENTRATED BY THE KIDNEY INTO
THE URINE AFTER ABOUT ONE HOUR.
SO WHAT YOU FIND IS THAT ONE
COULD ADMINISTER THIS MATERIAL,
COLLECT THE URINE IN AN HOUR,
AND ONE WOULD HAVE THE CLEAVAGE
PRODUCTS ASSOCIATED WITH -- IN
THE TUMOR INSTEAD NOW IN THE
URINE SAMPLE.
SO SORT OF NONINVASIVE WINDOW TO
THE TUMOR MICROENVIRONMENT.
SO WE INVENTED THIS TOOL AND
FIRST IN VITRO, HERE'S FOR
EXAMPLE ONE OF THESE SENSORS
SENSITIVE TO THROMBIN.
WE THEN STARTED TO MAKE A WHOLE
LIBRARY OF THESE MATERIALS SO WE
COULD QUERY PROTEASES ACROSS
MANY OF THE DIFFERENT CLASSES,
WHEN I
WHAT I MENTIONED.
WHEN I PUT THEM IN VIVO, THEY
WORKED AS I DESCRIBED.
FOR EXAMPLE, THIS IS A MATERIAL
THAT'S SENSITIVE TO MMP2, AND IN
A MOUSE MODEL OF LIVER FIBROSIS.
SO THESE MATERIALS HAVE BEEN
ADMINISTERED INTRAVENOUSLY IN
OUR LIVER TARGETED, AND IN THIS
MOUSE MODEL OF FIBROSIS, WHERE
THERE'S MMP2, THE MATERIALS ARE
ACTIVATED.
YOU CAN SEE IN AN HOUR THAT THE
BLAH DIDDER IS LIGHTING
BLADDER IS LIGHTING UP AS I
SHOWED YOU IN THE VIDEO.
SO THAT'S ONE THING.
YOU CAN MAKE A HIGHLY SPECIFIC
AND SENSITIVE TEST SO WE
BARCODED THE SENSORS USING MASS
SPECTROMETRY.
WE MAKE DIFFERENT MATERIALS WITH
DIFFERENT TETHERS, AND EACH OF
THE TETHERS, WHEN CLEAVED, WILL
RELEASE A DIFFERENT BARCODE.
SO YOU COLLECT THE URINE, AND
THEN YOU CAN MASS SPEC THE URINE
AND THAT GLIF YOU GIVE YOU A QUANTITATIVE
READOUT OF EACH DIFFERENT SENSOR
IN VIVO.
OKAY.
THAT'S A LOT TO DIGEST, BUT THIS
IS BASICALLY HOW IT WORKS.
YOU GIVE AN ENSEMBLE OF
MATERIALS, THEY GO TO THE
MICROENVIRONMENT OF INTEREST,
THEY'RE ACTIVATED BY RESIDENT
PROTEASES, AND THE FRAGMENTS,
THE BARCODES, COME OUT AN HOUR
LATER IN THE URINE.
AND YOU CAN USE THIS POTENTIALLY
AS A WINDOW INTO BIOLOGY IN THE
BODY THAT WOULD BE DIFFICULT TO
ACCESS OTHERWISE, AND BECAUSE OF
THE AMPLIFICATION, WE'RE HOPEFUL
THIS WILL ALLOW US EARLIER
DETECTION OF THE DISEASE.
SO I'M GOING TO SKIP THE DETAILS
ON THIS EXAMPLE WHERE WE'VE DONE
IT FOR LUNG CANCER, BECAUSE I'M
RUNNING SHORT ON TIME.
AND JUST SORT OF SUMMARIZE THAT
THIS IS A PRETTY LARGE BODY OF
WORK THAT WE'VE NOW PUBLISHED,
AND WHAT WE'VE LEARNED IS THAT
THIS IS A HIGHLY SENSITIVE TOOL
SO FAR IN MOUSE MODELS.
SO IN MICE, WE CAN DETECT
LESIONS THAT ARE ABOUT
THREE CUBIC MILLIMETERS, AND SO
FAR THIS IS QUITE A BIT MORE
SENSITIVE THAN BOTH PROTEIN AND
CIRCULATING DNA.
IT'S HIGHLY SPECIFIC.
NOW OF COURSE ANIMALS ARE
VERY -- WHEN WE GET INTO HUMAN
POPULATIONS, WE HAVE TO SEE HOW
MANY PROBES WE NEED REALLY TO
MAKE THIS BOTH SENSITIVE AND
SPECIFIC, BUT SO FAR WE CAN
MULTIPLEX TO 19 PROBES AND WE'VE
BEEN ABLE TO CLASSIFY THINGS
VERY READILY.
THEN WE'VE MADE A BUNCH OF
DIFFERENT VERSIONS OF THESE SO
YOU CAN HAVE NOT JUST A MASS
SPEC-BASED TEST BUT AS I'LL SHOW
YOU IN A MINUTE, YOU CAN DO THE
READ YOWLT ON PAPER OR OUT ON PAPER OR BY
BREATHALYZER, WHICH WE THINK
MIGHT HAVE CLINICAL UTILITY.
AS BEFORE, THIS WORK IS BEING
TAKEN FORWARD BY A STARTUP,
WHICH JUST FINISHED ITS PHASE
1 CLINICAL TRIAL OVER THE
PANDEMIC AND IS POISED TO MOVE
FORWARD TO ACTUALLY TRY AND
REPLACE LIVER BIOPSY OR A
DISEASE CALLED NASH,
NON-ALCOHOLIC SEATTLE HEPATITIS.
SO I KNOW I WENT QUICKLY THROUGH
THAT EXAMPLE.
I JUST WANT TO TALK TO YOU A
LITTLE BIT ABOUT HOW ONE MIGHT
THINK ABOUT BUILDING ON THIS AND
INTERFACING WITH CLINICIANS.
SO IT'S POSSIBLE THAT URINE IS
SUCH AN AMAZING BIOFLUID THAT WE
COULD ENVISION MAKING A PAPER
DIAGNOSTIC IN THE WAY YOU'VE ALL
SEEN COVID DIAGNOSTICS.
SO IN FACT, WE HAVE THE FOURPLEX
VERSION OF THIS THAT WE'VE PUT
ON PAPER.
THAT WE ENVISION COULD BE USED
AT THE POINT OF CARE.
IT STILL TAKES ABOUT AN HOUR TO
DEVELOP.
SO THE OTHER THING THAT WE WERE
CHALLENGED TO DO BY ONE OF OUR
CLINICAL COLLABORATORS WAS MAKE
A BREATHALYZER FOR THE LUNG
CANCER APPLICATION.
SO WE'VE DONE THAT AND PUBLISHED
THAT A COUPLE YEARS AGO NOW, AND
WE'RE WORKING WITH A COMPANY IN
THE U.K. CALLED ALSTONE.
IN THIS USE CASE, WHAT'S DONE IS
YOU INHALE THE SENSORS, AND WHEN
THEY'RE ACTIVATED, INSTEAD OF
TURNING FOO A URINE INTO A URINE READOUT,
YOU EXHALE A VOLATILE, AND THE
VOLATILE HAS ZERO BACKGROUND
BECAUSE IT'S COMPLETELY
SYNTHETIC.
SO IT'S VERY SENSITIVE AND THE
PEAKS COME UP AT ABOUT 10
MINUTES, SO IT'S A 10-MINUTE
TEST.
AGAIN, WE'RE JUST GETTING
STARTED, BUT WE ENVISION THAT
THIS MIGHT BE A WAY FORWARD FOR
SORT OF CHANGING DIAGNOSTICS.
THEN THE LAST EXAMPLE I'LL GIVE
IS, IF ONE, IN FACT, IDENTIFIES
CANCER EARLY IN A PATIENT'S
JOURNEY, THE VERY NEXT QUESTION
AS A CLINICIAN, OR ONE NEXT
QUESTION WOULD BE TO IDENTIFY
WHERE THE LESIONS ARE.
SO WHAT'S THE TISSUE OF ORIGIN
AND HAS THE TUMOR SPREAD.
SO IN RECOGNITION OF THAT, WE
MADE A VERSION OF THE SENSOR
THAT NOT ONLY ALLOWS LONGITUDAL
URINARY MONITORING, BUT WHEN THE
URINE SIGNAL TURNS POSITIVE, YOU
COULD LOAD THIS MATERIAL WITH A
PET PROBE, SO THIS IS COPPER 64.
AND IN THIS CASE, THEN, YOU CAN
SEE THAT YOU CAN, IN THIS CASE
IDENTIFY LIVER METASTASES WITH
THE VERY SAME PROBE AFTER THE
URINE TEST.
SO THE IDEA HERE IS THAT
MULTIMODAL AGENTS MAY BE HELPFUL
TO CLINICIANS THAT ARE TRYING TO
MAKE DECISIONS FOR PATIENTS.
SO ON THE NANOSIDE, I'M SHOWING
YOU THAT I THINK ENSEMBLES OF
NANOSENSORS COULD BE USEFUL FOR
MONITORING DISEASE.
I SHOWED YOU A CASE STUDY IN
LUNG CANCER, AND SOME PRODUCT
CONCEPTS THAT WE'RE TRYING TO
TAKE FORWARD TO MAKE THIS USEFUL
FOR OUR CLINICAL COLLEAGUES.
I'D LIKE TO JUST CLOSE UP WITH
SOME THOUGHTS ABOUT HOW TOOLS
COULD BE USEFUL MORE BROADLY TO
THE FIELD, AND JUST SORT OF
OBSERVE THE MOMENT THAT WE'RE AT
IN TIME.
SO IN ORDER FOR THE TOOLS REALLY
TO MAKE AN IMPACT ON MODERN
MEDICINE, WE NEED DIFFERENT
FIELDS TO COME TOGETHER.
YOU NEED TO CROSS THAT BRIDGE
THAT WIN WAS ALLUDING TO.
AND IN THE EXAMPLE I'VE GIVEN
YOU, THE MINIATURIZATION
REVOLUTION AND NUCLEIC ACID
THERAPEUTICS AND MANY DIFFERENT
STRANDS OF BIOLOGY HAVE COME
TOGETHER, AND REALLY WE'RE
POISED NOW, I THINK, IN THIS
DECADE TO TACKLE SOME OF THE
HARDEST PROBLEMS IN CANCER
RESEARCH.
EARLY DETECTION, RECALCITRANT
TUMOR THERAPY, METASTATIC
DISEASE, EVEN THINKING ABOUT
GLOBAL ONCOLOGY.
SO IT A REALLY EXCITING TIME TO
THINK ABOUT BRIDGE BUILDING AND
BRINGING THINGS TOGETHER TO
TACKLE SOME OF THESE GRAND
CHALLENGES.
MYSELF AND MY COLLEAGUES AT MIT
WELCOME YOU TO COME VISIT US.
WE THINK ABOUT THIS ALL THE
TIME.
WE HAVE ABOUT 200 TRAINEES IN
OUR CENTER FOR NANOMEDICINE,
THINKING ABOUT THIS SORT OF
CONVERGENCE OF IDEAS.
AND THE LAST IMPORTANT
INGREDIENT, I THINK, FOR MAKING
AN IMPACT IS HAVING ALL THE
RIGHT PEOPLE AT THE TABLE.
SO THAT'S SOMETHING THAT I'VE
REALLY WORKED ON OVER MY CAREER,
AND I'LL JUST SHOW YOU SOME
PICTURES IN THIS LAST MINUTE OR
SO TO SHARE SOME OF THE THINGS
THAT WE DO AT MIT ALONG THESE
LINES.
SO THIS IS AN OUTREACH WORKSHOP
RUN BY THE SOCIETY OF WOMEN
ENGINEERS FOR MIDDLE SCHOOL
GIRLS TO BRING THEM TO MIT.
THESE ARE ACTUALLY MY TWO
DAUGHTERS.
THEY'RE A LITTLE BIT OLDER NOW,
ONE OF THEM IS IN COLLEGE.
THIS IS A SOCIAL MEDIA CAMPAIGN
WITH TWO DEPARTMENT HEADS AT
MIT.
#I LOOK LIKE AN ENGINEER, TO
CHANGE PERCEPTIONS OF
ENGINEERING.
THIS IS A POSTDOC PROGRAM TO
DEVELOP LEADERS IN OUR POSTDOC
COMMUNITY THAT WE RUN AND WE
CALL IT THE CONVERGENCE SCHOLAR
PROGRAM.
AND I'VE BEEN MOST RECENTLY
WORKING ON WOMEN
ENTREPRENEURSHIP, WOMEN FACULTY
ENTREPRENEURSHIP AFTER HAVING
COLLABORATED WITH SUSAN HOTFIELD
AND NANCY HOPKINS AT MIT TO NOTE
THAT WOMEN ARE UNDERFOUNDING
COMPANIES IN THE LIFE SCIENCES.
IF WE JUST LOOK AT MIT IN THE
LAST 18 YEARS, THERE COULD HAVE
BEEN 40 MORE COMPANIES FROM
WOMEN FACULTY LABS.
SO THIS IS AN OBSERVATION THAT
WE'RE SHARING, AND WE HAVE LOTS
OF IDEAS ABOUT HOW TO IMPROVE
THAT, INCLUDING SOMETHING THAT
I'M VERY PROUD OF THAT'S ONGOING
NOW CALLED THE MIT FUTURE
FOUNDER PRIZE COMPETITION.
THEY HAVE THESE NINE AMAZING
WOMEN PARTICIPATING.
AND WE'LL BE STREAMING A
SHOWCASE WITH THEIR PITCHES
ONLINE ON MAY 5TH AS THEY START
TO THINK ABOUT HOW TO BRING
THEIR IDEAS FORWARD TO PATIENTS.
SO WITH THAT, THANK YOU VERY
MUCH FOR YOUR ATTENTION.
HOPEFULLY I'VE CONVINCED YOU
THAT MAKING NEW TOOLS IS AN
IMPORTANT PART OF FUTURE, AND I
REALLY COULDN'T THANK MY LAB AND
MY ALUMNI AND MY COLLABORATORS
AND OUR FUNDING SOURCES ENOUGH.
THANK YOU.
>> SANGEETA, ON BEHALF OF
EVERYONE, REALLY, THANK YOU FOR
INTRODUCING MOST OF US TO THIS
EXCITING NEW WORLD OF ENORMOUS
POTENTIAL, GREAT EXCITEMENT AND
GREAT OPPORTUNITY FOR BRIGHT
YOUNG PEOPLE TO CONTINUE AND
EXPAND THIS.
WE HAVE SEVERAL QUESTIONS THAT
HAVE COME UP.
ARE THERE SPECIFIC PROTEASES
ASSOCIATED WITH SPECIFIC KINDS
OF TUMORS, SO THAT THE ANALYSIS
GIVES SOME CLUE AS TO THE
IDENTITY OF THE TUMOR?
>> YES, THIS IS A GREAT
QUESTION.
AND ONE THAT I GLOSSED OVER OUR
KIND OF PIPELINE.
SO THERE ARE TUMOR-SPECIFIC --
THERE ARE BOTH TUMOR-SPECIFIC
PROTEASES AND THERE ARE ALSO
SORT OF PANCANCER PROTEASES.
THE WAY WE FIND THE
TUMOR-SPECIFIC ONES TYPICALLY IS
TO START WITH THE CANCER GENOME
ATLAS, WHICH IS A GREAT
RESOURCE.
AND JUST CLASSIFY THOSE 550.
SO FAR EXAMPLE, IN THE LUNG
CANCER MODEL THAT I SHOWED YOU,
WE PICKED THE TOP 20
DISREGULATED CANCERS, PROTEASES,
AND THEN ANOTHER FILTER THAT WE
NEEDED TO ADD WAS ACTUALLY
COMMON COMORBIDITIES THAT LUNG
CANCER PATIENTS MAY HAVE, FOR
EXAMPLE, IF THEY'RE SMOKERS OR
THEY HAVE COPD, THOSE ALSO HAVE
PROTEASES ASSOCIATED WITH THEM,
SO WE DELETE THOSE FROM THE
SIGNATURE SO THAT THEY'RE SORT
OF SPECIFIC TO, IN THIS CASE,
NON-SMALL CELL LUNG CANCER.
>> ANOTHER INTERESTING QUESTION
IS, CAN YOU VISUALIZE PERHAPS
THAT NANOSENSORS BE DEVELOPED TO
HELP MONITOR THE PROGRESSION OF
TISSUE REGENERATION?
FOR EXAMPLE, I'M SURE YOU KNOW
THAT ONE OF THE BIG PROBLEMS IN
LIVER INJURY IS TO DECIDE
WHETHER A PATIENT NEEDS AN
EMERGENCY TRANSPLANT OR WHETHER
THE LIVER IS REALLY BEGINNING TO
REGENERATE.
THIS IS STILL A VERY DIFFICULT
QUESTION TO ANSWER.
DO YOU THINK THERE IS SOME
POSSIBLE ROLE OF NANOSENSORS IN
A SITUATION LIKE THAT?
>> I HAVEN'T THOUGHT EXACTLY
ABOUT THAT USE CASE.
SO IT WOULD BE FUN TO TALK MORE
ABOUT IT, WIN.
BUT I THINK WHAT WE'VE SEEN, FOR
EXAMPLE, IN JUST REJECTION, FOR
EXAMPLE, WHICH IS T-CELL
MEDIATED, BUT T-CELLS KILL BY
GRANZYME, AND GRANZYME ACTUALLY
IS A PROTEASE.
SO MY FORMER POSTDOC PUBLISHED A
VERY NICE PAPER COLLEAGUES AT
EMORY SHOWING THEY COULD DETECT
REJECTION EARLY USING A PROTEASE
SENSOR.
SO I DO THINK WITH 550 TO CHOOSE
FROM, IT OFTEN THE CASE THAT WE
CAN POINT IT AT A DISEASE.
>> THERE WAS ALSO A QUESTION
ABOUT IN STUDIES FROM THE PAST
WHERE PEOPLE HAVE PUT
HEPATOCYTES IN DIFFERENT MEDIA,
COLLAGEN AND WHATNOT AND PLANTED
THEM IN THE PERITONEUM, THAT
WITHIN A SHORT PERIOD OF TIME,
GUY PRO CYST OCCURS AND THE
BLOOD SUPPLY IS CHOKED OFF AND
THEY DON'T LIVE VERY LONG, AND I
GUESS THE OTHER PART OF IT IS,
THEY'RE SECRETING A DETERGENT
PRESUMABLY OF BIOACID, WHICH
ISN'T SO HEALTHY TO HAVE JUST
FLOATING AROUND.
SO WHAT IS THERE ABOUT YOUR
PREPARATIONS THAT APPARENTLY
THOSE EVENTS DON'T HAPPEN?
WHY NOT?
>> YEAH.
THAT'S A GREAT QUESTION AND
ACTUALLY THE -- I THINK YOU
KNOW, THE BILE DUCT QUESTION
HAUNTED ME EARLIER IN MY CAREER.
WE ARE TRYING TO BUILD A BILE
DUCT BUT I THOUGHT WE HAD TO DO
THAT FIRST UNTIL JIM BOIL AT
YALE POINTED OUT TO ME THE
HEPATOCYTES THAT PERSIST IN THE
SPLEEN WHEN WE DO THOSE
INJECTIONS ACTUALLY DON'T HAVE A
BILE DUCT EITHER AND THEY DON'T
BECOME CHOLESTATIC.
THAT GAVE ME HOPE.
SO ACTUALLY OUR INTRAPERITONEAL
HEPATOCYTES ARE DOWNREGULATING
THE BIOACID PRODUCTION AXIS, AND
THE TRANSCRIPTIONAL DATA KIND OF
SUPPORTS THAT, SO I THINK THAT'S
WHY THEY'RE NOT TOX GUYING
THEMSELVES WITH DETERGENT.
THE REASON I THINK THEY'RE NOT
FIBROSING IS BECAUSE OUR
MATERIAL IS A DEGRADABLE
MATERIAL, SO ONCE THE
HEPATOCYTES GET VASCULARIZED,
THE MATERIAL DEGRADES OVER THE
COURSE OF A COUPLE OF WEEKS.
THERE'S NO FOREIGN BODY
REACTION.
>> THAT'S VERY INTERESTING.
WE HAVE SOME QUESTIONS ABOUT THE
MALARIA PROJECT.
IS THE HYPNOZOITE IN A SPECIAL
COMPARTMENT, A MEMBRANE-LIMITED
COMPARTMENT OR SOMETHING, AND
WHAT MAKES IT DIFFERENT FROM THE
OTHER SORT OF VACUOLES OR
WHATEVER YOU CALL THEM, WHERE
THE VIVAX IS THAT'S ACTUALLY
BECOME ACTIVE?
IS THERE SOMETHING SPECIAL ABOUT
THE CELL BIOLOGY OF THE HIP
ZOITE?
>> THAT'S A GREAT QUESTION.
SO FAR WE'VE STAINED ONLY FOR A
COUPLE OF MARKERS OF THE VACUOLE
AND SEEN NO DIFFERENCES IN THE
MEMBRANE AROUND THE HYPNOZOITE
VERSUS THE REPLICATING FORM.
BUT AS I SORT OF BRIEFLY ALLUDED
TO, IT DOES SEEM THAT THE
HYPNOZOITE IS MAKING PROTEASES
CALLED VIVOPANES.
THEY SEEM IMPORTANT IN DIGESTING
HOST PROTEINS AND MAINTAINING
QUIESCENCE.
IF YOU INHIBIT THOSE, ACTUALLY
THE PARASITE DIES, SO IT'S NOT
CLEAR TO ME IF THAT SAME PROCESS
IS LAPPING IN THE REPLICATING
FORMS.
>> VERY INTERESTING.
I SEEM TO REMEMBER BUT I MAY BE
WRONG ABOUT THIS, THAT THERE
WERE PEOPLE INFECTED WITH VIVAX
WHO RECOVERED FROM SEVERAL
EPISODES AND THEN SEEM TO BE
PERFECTLY NORMAL AND THEN MAYBE
AS LONG AS FIVE YEARS, 10 YEARS
LATER, FOR ONE REASON OR
ANOTHER, THEY WERE GIVEN A
CORTICOSTEROID FOR SOME --
DISEASE AND BINGO, THE VIVAX
RETURNED IN ITS VARYING FORM.
IS THERE SOME RELATIONSHIP
BETWEEN THAT CLINICAL EVENT AND
WHAT YOU'RE DESCRIBING IN THE
CULTURED CELLS?
>> YEAH, I THINK THESE ARE THE
QUESTIONS WE CAN NOW ASK.
THE OTHER ONE I'VE BEEN -- THE
OTHER DATASET THAT'S REALLY
FASCINATING IS THAT FROM OLD
SORT OF MILITARY MOVEMENTS THAT
VIVAX CLEARED SOLDIERS WHO WERE
INFECTED WITH VALCIFIRIM, WOULD
HAVE THEIR VIVAX FLARE.
SO THERE'S A LOT OF INTERESTING
HYPOTHESES I THINK WE COULD NOW
TEST.
>> WELL, THAT'S VERY
INTERESTING.
WHY DID YOU PICK VIVAX AND NOT
VALCIPIR MI OR ANY OF THE
OTHERS?
IS THERE SOME REASON?
>> WE WANTED TO DO ANY OF THE
HUMAN MALARIAS, SO ACTUALLY WE
ACHIEVED VALCIPIRIM FIRST, BUT
WE WANTED TO DO -- WE ALWAYS ARE
TRYING TO DO SOMETHING WITH OUR
TOOLS THAT HAD NEVER BEEN DONE,
THAT NO OTHER TECHNIQUE COULD
APPROACH.
SO WE DID THAT AND OTHERS HAD
DONE IT ACTUALLY PREVIOUSLY AND
WE SORT OF MADE IT HIGH
THROUGHPUT, BUT NOBODY HAD EVER
DONE VIVAX.
I HAVE TO SAY, IT WAS INCREDIBLY
DIFFICULT.
IT TOOK US 10 YEARS.
BUT THAT'S WHY WE CLOSE TO DO IT
BECAUSE WE FELT LIKE WE REALLY
COULD OPEN SOME NEW BIOLOGY
DOORS THERE.
>> HOW DOES -- ANOTHER QUESTION,
HOW DOES THE PARASITE GET FROM
THE BLOOD THROUGH THE SIGH SINUSOIDAL
IF HENESS TRAL BARRIER TO THE
HEPATOCYTE?
>> SO THE SPORE ZOITE TRAVERSES
ALONG FREU THE FENESTRATED
EPITHELIUM AND IT GLIDES, THIS
HAS BEEN STUDIED BY MARIA MODA
AND OTHERS.
IT ACTUALLY CAN BREAK THROUGH
SEVERAL HEPATOCYTES BEFORE IT
SETS UP SHOP IN ONE.
SO IT HAS A GLIDING MECHANISM.
YOU CAN ACTUALLY SEE IT IN CULL
FEWER IF YOU PUT
CULTURE, IF YOU PUT A SPORE SEW
IETD ON A GLASS SLIDE, IT WILL
LEAVE THESE LITTLE SPIRALS.
>> BUT ISN'T IT TOO BIG TO GO
THROUGH THE --
>> IT IS, IT IS BIG.
>> LIKE 100-NANOMETERS AT BEST.
>> THAT'S A GOOD QUESTION.
SO FOR A WHILE, THERE WAS A
THEORY THAT THEY WERE ACTUALLY
FIRST INVADING KUFER CELLS AND
THEY WERE SHEPPARDING ACROSS THE
SINUSOID.
I THINK THERE'S DATA ON BOTH
SIDES OF THAT, AND ONLY IN
RODENTS, SO I'M NOT SURE ANYONE
IS CONVINCED THAT THE KUFER
CELLS ARE REQUIRED.
>> DO YOU HAVE KUFER CELLS IN
YOUR OPERATION?
>> I DON'T.
BUT I WILL SAY THAT OUR
INFECTION RATES ARE VERY LOW
COMPARED TO WHAT YOU EXPECT.
WE KNOW THAT VERY FEW -- I MEAN,
ONE PARASITE CAN CAUSE A
PRODUCTIVE INFECTION, AND IN
OURS, WE PUT THOUSANDS OF
PARASITES IN SO THE EFFICIENCY
IS MUCH LOWER.
>> SO HERE'S A PROVOCATIVE
QUESTION FOR YOU.
WHAT DO YOU THINK THE NEXT
DEVELOPMENT IN SEMICONDUCTORS IS
GOING TO BE THAT'S GOING TO
INFLUENCE WORK SUCH AS WHAT
YOU'RE DOING.
WHERE DO YOU THINK THAT WHOLE
FIELD -- I MEAN, WE'VE GOTTEN
DOWN TO THE POINT NOW OF
NANOMETERS, MY KNEE CHIPS.
MINI CHIPS.
WHAT DO YOU SEE HAPPENING NEXT
HAPPENING IN THAT FIELD THAT
SEEMS TO BE DRAMATICALLY MOVING
ALL OVER THE WORLD?
>> THAT'S A GOOD QUESTION.
I MEAN, I THINK WHAT'S
INTERESTING NOW IS NOT JUST THE
ADVANCEMENTS THAT WILL HELP IN
HARDWARE, AND SO THE MAIN WAYS
THE FIELD IS THINKING ABOUT IT
IS TO MAKE THREE-DIMENSIONAL
COMPUTERS, SO INSTEAD OF 2D, 3D,
AND THEN ALSO QUANTUM COMPUTING,
WHICH IS A COMPLETELY DIFFERENT
WAY OF DOING COMPUTATION.
BUT THE OTHER REALLY INTERESTING
THING NOW IS THAT IT'S NOT JUST
HARDWARE, IT'S ALSO WHAT
COMPUTATION ENABLES US IN
BIOLOGY.
AND SO THAT -- I MEAN, JUST FOR
EXAMPLE THE SINGLE CELL DATA, WE
COULDN'T HAVE DONE THAT KIND OF
ANALYSIS 10 YEARS AGO, JUST
BECAUSE OF THE SHEER VOLUME OF
THE DATA OR THE MACHINE LEARNING
IN OUR DIAGNOSTIC SIGNATURES.
SO I THINK WHAT'S COMING NOW IN
THIS CHAPTER IS MACHINE LEARNING
AND ARTIFICIAL INTELLIGENCE ARE
REALLY CHANGING THE WAY WE HAS
HANDLE DATA AS BIOLOGISTS
BECAUSE THERE'S MORE DATA THAN
WE CAN COMPREHEND SO WE NEED
THOSE TOOLS.
>> WELL, IT WOULD BE VERY
EXCITING TO SEE WHAT'S GOING TO
HAPPEN IN THE NEXT YEARS TO PUSH
THIS FURTHER.
LISTEN, ON BEHALF OF EVERYBODY,
WE WANT TO REALLY THANK YOU
ENORMOUSLY, AND LOOK FORWARD TO
SEEING YOU IN THE NEAR FUTURE.
>> THANK YOU.
>> SO THANKS AGAIN, AND WE
GREATLY APPRECIATE YOU SPENDING
YOUR TIME GIVING THIS COMBINED
WALS DEMYSTIFYING SESSION.
IT WAS SUPERB.
>> THANK YOU.
IT WAS GREAT TO SPEND THE
AFTERNOON WITH YOU.
AS ALWAYS.
>> YES, THANK YOU, EVERYONE.