>> GOOD AFTERNOON.
THANKS FOR COMING IN PERSON.
IT'S A PLEASURE TO INTRODUCE
JAKOB, UNDERGRADUATE AT
DARTMOUTH, UC-BERKELEY FOR
GRADUATE STUDIES, DEVELOPED THE
SYSTEM DELIVERING FLAGELLAN INTO
THE CYTOSOL AND SHOWING THEY ARE
AN IMPORTANT OUTPIT OF
ACTIVATION.
HE WENT TO UCSF, POSTDOC WORK
WITH RICH LOCKSLY, PUBLISHED
WHAT'S A SEMINAL STUDY
IDENTIFYING MURKY CHEMOSENSORY
EPITHELIAL CELLS AS DOMINANT
SOURCE OF INTERLEUKIN 25 THAT
ACTIVATES TYPE 2 INNATE LYMPHOID
CELLS IN THE INTESTINE, THE
FIRST LINK BETWEEN INTESTINAL
SPECIFIC CELL TYPE AND
ACTIVATION OF TYPE 2
INFLAMMATION.
FROM THERE HE STARTED
INDEPENDENT LAB AT UNIVERSITY OF
WASHINGTON IN SEATTLE,
CONTINUING TO STUDY INITIATORS
OF TYPE 2 INFLAMMATION,
INDEPENDENT GROUP MADE ONE OF
THE -- ANOTHER IMPORTANT
CONTRIBUTION TO TRY TO
UNDERSTAND HOW THE TUFTS CELLS
SENSE EXOGENOUS STIMULI AND
EXTENDING FROM OUR CANONICAL
RECOGNITION PARADIGM THE SHOW
METABOLITE IS A TRIGGER FOR CELL
ACTIVATION THAT TRIGGERS TYPE 2
INFLAMMATION, CONTINUING TO
STUDY IMPORTANT DETAILS IN THIS
BIOLOGY, REALLY EMERGED AS THE
KEY FIGURE IN OUR UNDERSTANDING
OF TUFT CELL TYPE 2 INTERFACE,
WE'RE IN FOR AN INTERESTING
TALK.
WELCOME, JAKOB.
[APPLAUSE]
>> OKAY.
THANK YOU VERY MUCH FOR THE
INTRODUCTION.
THANK YOU FOR COMING.
THIS IS MY FIRST TIME ON THE NIH
CAMPUS, REALLY EXCITING.
IT'S BEEN A FUN DAY.
AND FEELS LIKE COMING TO THE
MOTHER SHIP.
SO I'M PLEASED TO BE HERE.
I'M GOING TO TALK PRETTY MUCH
ENTIRELY ABOUT TUFT CELLS, WE
HAVE PROJECTS DEVELOPING IN THE
LAB NOW THAT ARE HEADING IN NEW
DIRECTIONS, AND REALLY LET ME
JUST SAY INITIALLY THAT THE
THEME OF THE LAB AND UNIFYING
INTEREST IS TYPE 2 IMMUNITY, THE
IMMUNE RESPONSE GENERATED BY
PARASITIC WORMS AND ALLERGYINS.
THERE HAVE BEEN DECADES OF
SEMINAL STUDIES TO UNDERSTAND
TYPE 2 IMMUNITY.
ANYBODY WHO SUFFERS FROM
ALLERGIES KNOWS CLINICAL
MANIFESTATIONS AND WE KNOW A LOT
OF CELLS DRIVING THAT, ADAPTIVE
CELLS, MORE RECENTLY THERE WAS
ADDITION OF THESE INNATE
LYMPHOID CELLS DISTINGUISHED BY
BEING RESIDENT IN THE TISSUE AND
THEREFORE READY TO RESPOND
ANYTIME.
AND WE KNOW THE DOMINANT
CYTOKINES THAT ARE DRIVING ALL
OF THIS.
BUT WHERE A LOT OF LACK OF
UNDERSTANDING REMAINS STILL IS
HOW YOU GET FROM THESE STIMULI,
DIVERSE SET OF STIMULI, TO
ACTIVATING CELLS IN THE
UNDERLYING TISSUE.
A LOT OF TIMES THESE STIMULI ARE
NOT INVASIVE, HOW DO YOU
TRANSMIT SIGNAL FROM THE OUTSIDE
WORLD TO INSIDE WORLD?
THE BARRIER OF COURSE IS A KEY
PART, EPITHELIUM, AND WHAT WE'VE
FOCUSED ON IS THIS ROLE OF
EPITHELIAL TUFT CELLS IN THIS
PROCESS.
SO, LET ME SAY -- TELL WHERE YOU
WE'RE GOING TODAY.
FIRST THING I THINK AT THIS
POINT PEOPLE HAVE MAYBE HEARD OF
TUFT CELLS BUT THEY ARE STILL --
I FIND PEOPLE DON'T NECESSARILY
KNOW THE HISTORY THAT WELL.
WE'LL TAKE TIME TO TELL YOU THE
BACKGROUND, BOTH OF OTHER
PEOPLE'S WORK AND WHERE WE SORT
OF HAVE TAKEN OVER AND WHAT WE
FOUND.
AND THEN I'LL TELL YOU ONE
RECENTLY PUBLISHED STORY THAT
HIGHLIGHTS THE WAY TUFT CELLS
INTERACT WITH THE EPITHELIUM TO
REGULATE ITS PHYSIOLOGY AND HOW
THAT LINKS WITH TYPE 2 IMMUNITY.
AND THEN UNPUBLISHED STUDY WHERE
WE'RE SORT OF EXTENDING THE TIME
SCALE IN WHICH WE THINK ABOUT
THIS, TO THINK ABOUT CHRONIC AND
ADAPT
ADAPTIVE RESPONSES AND ROLE OF
TUFT CELLS ESPECIALLY
INTERSECTING WITH Th2s.
TUFT CELLS HAVE BEEN KNOWN ABOUT
FOR MORE THAN 60 YEARS BECAUSE
WHEN PEOPLE STARTED TAKING
ELECTRON MICROSCOPY IMAGES, THEY
IMMEDIATELY SAW THAT EVERY ONCE
IN A WHILE, RARELY, THEY WOULD
FIND A CELL THAT LOOKED
DIFFERENT, DEFINED BY A TUFT AT
THE TOP.
SCANNING E.M. SHOWS I THE WAY
THE TUFT OF THE TUFT CELL
CONVERGES UP OUT OF THE
EPITHELIAL BARRIER AND REACHES
INTO THE LUMEN OF THE TISSUE
THAT IT'S IN.
AND SO THERE WAS REALLY
BEAUTIFUL EARLY E.M. WORK THAT
LOOKED AT THE CELL BIOLOGY OF
THESE THINGS, A LOT OF
PHENOTYPING, JUST IDENTIFYING
WHERE THEY WERE.
THEY FOUND THEY WERE RARE CELLS
AND THEY WERE IN LOTS OF MUCOSAL
BARRIERS, UP AND DOWN THE
INTESTINAL TRACT, PARTS OF
AIRWAY, TRACKA, NASAL PASSAGE
BUT NOT THE LUNG.
INTERESTINGLY IN THE THYMUS.
THE THING LACKING WAS ANY
UNDERSTANDING OF FUNCTION.
THIS WAS JUST NOTICING THERE ARE
UNUSUAL CELLS.
AND THAT STARTED TO CHANGE IN
THE LATE '90s, EARLY 2000s,
REALLY BECAUSE OF PEOPLE WHO
WERE STUDYING TASTE
TRANSDUCTION, AND THEY REALIZE
THE THE TOOLS THEY WERE BUILDING
WERE LIKE THE ANTIBODIES AND
REPORTER MICE WERE ALSO MARKING
THESE RARE CELLS IN THE
INTESTINE, AND IN OTHER PLACES,
THESE TUFT CELLS.
AND SO ONCE WE HAD THE FIRST
TRANSCRIPTOME FOR TUFT IT BECAME
CLEAR THE SHARED PROGRAM BETWEEN
TYPE 2 TASTE RECEPTOR CELLS AND
BETWEEN THE TUFT CELLS, AND THIS
IS PARTICULARLY TRUE FOR KIND OF
THE INTERNAL WORKINGS OF THE
CELL AND TRANSDUCTION PATHWAYS.
SO THEY BOTH SHARE THESE
SPECIALIZED SIGNAL THROUGH PLC
BETA2, MOST IMPORTANTLY THIS
TRPM 5 CHANNEL, CALCIUM GATED
SODIUM CHANNEL THAT DEPOLARIZES
CELLS, HOW TASTE SIGNALING
THROUGH RECEPTORS IS CONVERTED
INTO A NEURONAL SIGNAL DOWN
BELOW.
SO TUFT CELLS HAVE THESE THINGS.
TURNS OUT ALSO THERE'S THAT
MASTER TRANSCRIPTION FACTOR FOR
THE TYPE 2 LINEAGE AND FOR TUFT
CELLS SO MICE LACKING THIS DON'T
HAVE ANY TUFT CELLS.
THE FIRST KIND OF UNDERSTANDINGS
OF FUNCTION EMENTIONED SOON
AFTER THAT, AND THIS WAS WORK
DONE IN THE AIRWAYS, RECOGNIZING
TUFT CELLS COULD BE ACTIVATED BY
SOME BACTERIA DERIVED LIGANDS
LIKE SENSING MOLECULES, FOR
EXAMPLE, THROUGH CANONICAL TASTE
RECEPTORS, THE FOCUS THAT HE
COULD TALK TO NEURONS IN THE
AIRWAYS AND INDUCE NEUROGENIC
INFLAMMATION AND STUFF LIKE
THAT.
WHAT REMAINS MYSTERIOUS WHAT
THEY WERE DOING IN THE
INTESTINE.
I STUMBLED INTO THIS AS A
POSTDOC, WE KNOW IL-25 WAS
IMPORTANT FOR TYPE 2 IMMUNE
RESPONSES, ESPECIALLY IN THE
INTESTINE, DIDN'T KNOW WHERE
CYTOKINE WAS COMING FROM, MADE A
REPORTER MOUSE, INSERTED
DOWNSTREAM AND LOOKED FOR RED
CELLS, FOUND THEM IN BARRIER
SITES, RARE, GREEN IS MARKING
THE EPCAM BARRIER IN THIS CASE
OF THE DUODENUM, MAYBE ONE IN
100 OR FEWER OF THE CELLS ARE
IL-25 PRODUCERS.
AND SO WHAT WE FIGURED OUT AT
THE TIME, THOSE WERE ALL TUFT
CELLS, EVERY ONE OF THESE IL-25
POSITIVE CELLS.
SO FAR WE'VE NEVER SEEN ANY
OTHER CELL TURN RED WITH THIS
REPORTER.
AND CONVERSELY EVERY TUFT CELL
AS IT WAS BORN AS PART OF THE
PROGRAM EXPRESSED IL-25 AT LEAST
TRANSCRIPTIONALLY.
WE THINK MORE HAPPENS LATER.
OKAY.
SO, THE OTHER THING THOUGH THAT
HAPPENS IS THAT THE NUMBERS OF
TUFT CELLS IS ASTONISHLY DYNAMIC
ESPECIALLY IN SMALL INTESTINE,
UNIQUELY IN THE SMALL INTESTINE
REALLY.
ON THE LEFT HERE ARE TWO -- YOU
WITH SEE TWO ENTIRE VILLI, ONLY
THREE TUFT CELLS MARKED WITH
THIS ANTIBODY FOR DCLK 1, SEVEN
DAYS AFTER PUTTING A WORM IN THE
MOUSE HAVE YOU DOZENS OF TUFT
CELLS IN THE SINGLE VILLUS,
MASSIVE HYPERPLASIA EMERGES
BECAUSE OF THE DYNAMICS OF THE
INTESTINAL EPITHELIUM.
SO THIS IS WHAT IT LOOKED LIKE
SCANNING E.M., LARGE VILLI IN
THE SMALL INTESTINE, AND SMALLER
CRYPTS DOWN BELOW.
THE STEM CELLS RESIDE AT THE
BASE OF THE CRYPT WITH PANNA
CELLS, GIVE RISE TO CELLS THAT
DIFFERENTIATE AS THEY MOVE UP,
ADOPT INTERNAL FATES IN THE
VILLUS, EVENTUALLY LOST.
MOST ABSORBED AT ENTEROCYTES,
LESS FREQUENT LINEAGES LIKE THE
GOBLET CELLS AND HORMONE CELLS,
AND TUFT CELLS AS WELL.
AND THE KEY THING IS THAT THESE
CELLS ARE SHORT-LIVED.
FOUR TO FIVE DAYS, REPLACE
BASICALLY THE ENTIRE LINING OF
THE EPITHELIUM, TRUE IN RODENTS
AND HUMANS.
AND SO IF YOU CAN CHANGE THE
OUTPUT FROM THIS STEM CELL
COMPARTMENT, YOU CAN COMPLETELY
CHANGE COMPOSITION AND FUNCTION
OF EPITHELIUM WITHIN DAYS.
SO THIS IS WHAT WE DESCRIBED
TOGETHER WITH PHILIP'S LAB IN
FRANCE AT THE TIME.
WE CALLED IT THE TUFT IL-2
CIRCUIT, WHAT'S HAPPENING IS
THAT WHEN THERE ARE WORMS
PRESENT IN THE LUMEN OF THE
SMALL INTESTINE TUFT CELLS
SOMEHOW RESPOND TO THEM.
RELEASE IL-25 AND THAT ACTS ON
THESE ILC 2s TO MAKE CANONICAL
TYPE 2 CYTOKINES.
THE 13 SIGNALS BACK TO SOMEWHERE
IN THE CRYPT.
WE DON'T FLOW IF IT'S STEM CELLS
OR SOME TRANSIT AMPLIFYING ZONE,
CELLS HAVE NOT FULLY DECIDED IF
THEY ARE GOING TO BE A TUFT
CELL, IT CAN EXPAND THIS TUFT
CELL LINEAGE AND SO ONCE YOU'VE
TURNED ON IL-15 YOU GET TUFT
CELL HYPERPLASIA, A FEED-FORWARD
TUFT IL-CIRCUIT.
IT FELT LIKE THERE ARE MISSING
LINKS, SIT AT THE BARRIER,
EQUIPPED WITH THINGS TO TALK TO
THE UNDERLYING TISSUE.
RIGHT AT THAT SAME TIME MICHAEL
AND WENDY'S LAB ARRIVED AT A
SIMILAR FINDING FROM A DIFFERENT
APPROACH, MICROBIOME LAB,
REALIZED NUMBERS OF ACTIVITY
CELLS WERE DIFFERENT IN IN-HOUSE
MICE AND JAK MICE AND TRACED
BACK TO TRICHOMONAS, COMMON IN
VIVARIUMS, AND ACTIVATE THE SAME
CIRCUIT DESCRIBED BEAUTIFULLY.
AND SO MICE LACKING ANY
COMPONENT OF THE CIRCUIT, EITHER
DON'T CLEAR WORMS OR DON'T SENSE
THE PROTUS.
IF YOU GET RID OF TUFT CELLS OR
IL-25, FOR EXAMPLE.
SO, WE'VE BEEN TRYING TO FILL IN
THESE GAPS AND UNDERSTAND HOW IS
THE SENSING WORKING, HOW ARE
PROTEUS AND WORMS DETECTION.
THE WORM DETECTION THAT WE DO
NOT UNDERSTAND YET REMAINS A
BIGGEST QUESTION, AND WHAT ELSE
ARE THEY DOING BESIDES MAKING
IL-25 AND HOW DOES SIGNALING AND
DIFFERENTIATION WORK.
ONE OF OUR FIRST IN SIGHTS WAS
SENSING OF SUCCINATE BY THE
FIRST TWO GRAD STUDENTS IN THE
LAB, TUFT CELLS ARE EQUIPPED
WITH SUCCINATE RECEPTORS THAT
SENSES EXTRACELLULAR SUCCINATE,
AND THAT CAN INDUCE CALCIUM FLUX
THAT WILL OPEN TRPM 5, AND SO IT
TURNS OUT IF YOU PUT SUCCINATE
IN THE DRINKING WATER OF THE
MICE, THAT SINGLE MOLECULE IS
SUSPICIOUS TO TURN ON THE ENTIE
CIRCUIT, THE MOUSE LOOKS LIKE
IT'S INFECTED WITH A WORM.
THIS PATHWAY IS REQUIRED FOR
SENSING OF THESE, WHICH MAKE A
LOT OF SUCCINATE UNDER ANAEROBIC
CONDITIONS, DISPENSABLE FOR THE
SENSING OF THE WORMS.
WE DON'T UNDERSTAND THAT
DICHOTOMY REALLY.
NOW OTHERS ALSO HAVE SHOWN THERE
ARE CIRCUMSTANCES OF BACTERIAL
DYSBIOSIS, ELEVATED SUCCINATE IS
SENSED BY TUFT CELLS AND TURNS
ON THIS CIRCUIT.
THIS WAS JACK'S SECOND PROJECT
IN THE LAB.
IN I ADDITION TO MAKING IL-25 ON
DEMAND SYNTHESIZE AND RELEASE
LIPID MEDIATORS, LTC 4
SPECIFICALLY, AND HE SHOWED HOW
THAT COOPERATES WITH IL-25 TO
RAPIDLY INDUCE CYTOKINE
PRODUCTION.
INTERESTINGLY THIS IS REQUIRED
WHEN THERE ARE WORMS,
DISPENSABLE WHEN A PROSIOUS, P-
PROTEUS, A SPLIT IN THE
PATHWAYS.
THOSE ARE THE GAPS WE'VE FILLED
IN.
YOU MAY WONDER, WELL, THAT'S
NICE IN THESE MICE BUT DOES THIS
HAVE ANYTHING TO DO WITH HUMANS?
I MEAN, THIS IS STILL VERY EARLY
DAYS, UNTIL RECENTLY JUST KNEW
THERE WERE TUFT CELLS IN HUMANS,
GOT SINGLE CELL DATA.
A NUMBER OF DATASETS NOW WHICH
SATISFYINGLY SHOW THAT HUMAN
TUFT CELLS EXPRESS BASICALLY THE
SAME PROGRAMS, FOR EXAMPLE YOU
CAN SEE THE SUCCINATE RECEPTOR
HIGHER IN THE SMALL INTESTINE
THAN COLON, SAME IN MICE.
TRPM 5 IS REALLY HIGH, GNAT 3,
AND THEN COMPONENTS OF THE
SYNTHESIS PATHWAY.
SEEMS TO BE VERY SHARED
TRANSCRIPTIONAL PROGRAMS AND
THEN A REALLY IMPORTANT
CONTRIBUTION JUST LAST YEAR
SHOWING HYPERPLASIA CAN ALSO
OCCUR IN HUMANS, THIS REQUIRED
OPTIMIZING ORGANOID CULTURE
CONDITIONS TO GROW AND
DIFFERENTIATE TUFT CELLS IN
HUMAN ORGANOIDS, YOU GET THIS
NICE HYPERPLASIA OF TUFT CELLS,
SIMILAR MECHANISM IN MICE AND
HUMANS.
OKAY.
SO, THAT'S MY VERY QUICK
BACKGROUND ON TUFT CELLS AND
WHERE WE'VE GOTTEN SO FAR.
I'M GOING TO TALK ABOUT THIS
PROJECT ABOUT EPITHELIAL
PHYSIOLOGY AND TUFT CELLS.
THIS CAME OUT OF A SIMPLE
QUESTION WHICH WAS WHY TUFT CELL
HYPERPLASIA HAPPENS.
THE THINGS WE KNEW THEY HAD THIS
SENTINEL FUNCTION, DETECTING
SOMETHING, EARLY ACTIVATORS.
WHY BOTHER MAKING MORE SENTINELS
IF YOU ALREADY DETECTED WHAT YOU
WANT TO DETECT?
AND WE THINK WE HAVE MAYBE
GETTING TOWARDS SOME
UNDERSTANDING OF THIS FROM WORK
DONE BY ANOTHER GRADUATE
STUDENT, TYLER, BILL UP AND
INTEREST IN ACETYLCHOLINE.
THEY ARE THE ONLY CELLS IN THE
INTESTINE THAT EXPRESS CHAT.
TYLER WANTED TO KNOW WHAT THAT
WAS FOR.
SO, ACETYLCHOLINE IS ASSOCIATED
WITH BEING NEUROTRANSMITTER, AND
SO PEOPLE OF IT MADE BY NEURONS
OR SIGNALING ON NEURONS, AND
CERTAINLY AGAIN IN THE AIR WAIST
THERE -- AIRWAYS THEY TALK TO
NEURONS, COULD BE TRUE IN THE
INTESTINE, BUT NOT REALLY WHAT
WE FOCUSED ON ANY PARTICULAR
PROJECT.
INSTEAD, WE STARTED THINKING
ABOUT ANOTHER IMPORTANT FUNCTION
FOR ACETYLCHOLINE IN THE
INTESTINE, IT DRIVES SECRETION
OF MUCUS, ANTIMICROBIAL
PEPTIDES, FLUID OR CHLORIDE IONS
THAT THEN PULL FLUID OUT OF THE
TISSUE, DEMONSTRATED OR ASSUMED
SOME COMING FROM ENTERIC NEURONS
BUT TYLER WANTED TO ASK WHETHER
THEY WERE CONTEXTS COMING FROM
TUFT CELLS.
HE ADOPTED THIS CLASSIC
PHYSIOLOGY TOOL, USING CHAMBER,
YOU HAVE TWO PHYSIOLOGICALLY
BUFFERED CHAMBERS, INSERT ON
THIS SLIDER HERE, INSERT
EPITHELIUM OF CHOICE, IN THIS
CASE SMALL INTESTINE HE PINNED
UP ON, POLARIZED WITH THE VILLI
ON ONE SIDE, BASAL SIDE ON THE
OTHER.
VOLTAGE CLAMP THIS AND MEASURE
HOW MUCH CURRENT YOU NEED TO
INJECT TO MAINTAIN THE SAME
VOLTAGE, AND THAT CURRENT IS
CALLED THE ISC, INDUCIBLE SHORT
CIRCUIT, PROPORTIONAL TO ION
MOVEMENT ACROSS EPITHELIUM.
YOU'RE MEASURING IN REAL TIME
ION FLUX ACROSS THE EPITHELIUM.
THIS IS WHEN TYLER USES SMALL
INTESTINE, BASELINE ISC,
STIMULATES WITH SUCCINATE WHICH
WE STARTED WITH BECAUSE IT WAS
THE ONLY LIGAND WE HAD, YOU GET
THIS VERY RAPID SPIKE IN THE
ISC, HAPPENING, STARTING IN
SECONDS, LASTS MINUTES, AND THEN
DROPS BACK DOWN.
IT IS KINETICALLY VERY SIMILAR
TO WHAT HAPPENS IF YOU STIMULATE
UP EPITHELIUM WITH ACETYLCHOLINE
MIMIC CASH CHARBACHOL, COMPLEX
WITH SODIUM.
SOME EFFECT OF SODIUM ALONE.
WE SWITCHED TO USING SYNTHETIC
AGONIST OF THE SUCCINATE
RECEPTOR THAT ELIMINATES THIS
CHLORIDE COMPONENT OF THE
RESPONSE.
AND THEN THIS IS PUBLISHED, SO
I'M GOING TO SUMMARIZE QUICKLY,
HE WAS ABLE TO USE KNOCKOUTS TO
SHOW THIS RESPONSE REQUIRED
SUCCINATE RECEPTOR, REQUIRED
TRPM 5 AGAIN, THAT KEY ION
CHANNEL IN THE TUFT CELLS, AND
AGAIN TUFT CELLS ARE THE ONLY
EPITHELIAL CELLS THAT EXPRESS
IT.
THIS IS A KNOCKOUT WITHOUT TUFT
CELLS, OTHERS ARE FINE.
THE TISSUE WAS RESPONSING TO THE
CHARBACHOL.
THIS REQUIRES ACETYLCHOLINE FROM
TUFT CELLS, USING A CRE WITH
CHAT FLUX LINE, YOU LOSE
RESPONSE TO THE LIGAND BUT NOT
TO THE CHARBACHOL.
SO, AGAIN, THERE'S TONS MORE
CHARACTERIZATION TYLER IN.
IN REAL CELL CONNECTED TUFT CELL
FUNCTION, MANIPULATE WERE
INHIBITORS AND KNOCKOUTS.
HE WAS ABLE TO MAP THIS PATHWAY
TO SHOW IT REQUIRED MUSCULAR
ACETYLCHOLINE RECEPTORS, TO SHW
THIS WAS CHLORIDE AND SUSTAIN
SECRETION YOU NEED UPTAKE, YOU
NEED THE RESPONSE UNIT LINKING
SENSING CAPACITY OF THE TUFT
CELL TO INSTANTANEOUS SORT OF
EFFECTOR FUNCTION OF FLUID
SECRETION, FUNDAMENTAL ASPECT OF
EPITHELIAL BIOLOGY AND
PHYSIOLOGY, MUCOSAL BIOLOGY.
AND IT'S REALLY CONSISTENT WITH
EMERGING THEME THAT TUFT CELLS
ARE USING ACETYLCHOLINE TO
COMMUNICATE WITH NEIGHBORING
EPITHELIAL CELLS, A BEAUTIFUL
SERIES OF PAPERS THAT HAS
SIMILARLY SHOWN THIS IN OTHER
TISSUES LIKE GALLBLADDER AND
AIRWAYS.
BUT OF COURSE I TOLD YOU WE'RE
TYPE 2 IMMUNITY LAB, WANTED TO
KNOW IF THIS HAD ANYTHING TO DO
WITH THE TYPE 2 IMMUNE RESPONSE.
TO ADDRESS THAT LET ME EXPLAIN
OUR CURRENT UNDERSTANDING OF HOW
YOU ELIMINATE WORMS FROM
INTESTINE.
IT'S A TWO-STEP PROCESS WHERE
THE FIRST IS A PRIMING PROCESS
THAT TAKES IN THE CASE OF THIS
HOOKWORM MODEL TAKES ABOUT SIX
DAYS.
AND THIS IS WHERE THE CIRCUIT IS
SO IMPORTANT.
YOU NEED TO SENSE THE WORMS,
MAKE THESE EFFECTORS THAT
ACTIVATE TYPE 2 SIGNALING,
AMPLIFY THROUGH THE FEED FORWARD
CIRCUIT.
THERE'S ACUTE EVENT AROUND DAY
7, CALLED WEEP AND SWEEP.
THE WEEP IS INCREASED FLUID AND
MUCUS PRODUCTION, DETACHES THE
WORM, THE SWEEP IS MORE HYPER
CONTRACTION OF THE SMOOTH MUSCLE
TO EXPEL THEM OUT OF THE
INTESTINE.
WHAT'S NOTABLE THAT BOTH OF
THESE PROCESSES CAN BE DIRECTLY
DRIVEN BY ACETYLCHOLINE, AND
WE'VE KNOWN FOR DECADES THAT
WORMS SECRETE A LOT OF
ACETYLCHOLINE ESTERASES, IF
PATHOGEN IS ANTAGONIZING
SOMETHING THAT'S PROBABLY
IMPORTANT PART OF THE HOST
DEFENSE.
DO YOU NEED TUFT CELL
ACETYLCHOLINE TO CLEAR WORMS OUT
OF THE INTESTINE?
YES, YOU DO.
THIS IS DELETING ONLY FROM TUFT
CELLS, ON DAY 5 THERE'S
EQUIVALENT COLONIZATION, WHETHER
OR NOT YOU HAVE CHAT.
BUT BY DAY 7 AND 9, YOU SEE THAT
THE WILD TYPE FUNCTIONAL MICE
ARE CLEARING BUT CHAT DEFICIENT
ARE DELAYED.
OKAY.
SO, WHAT IS IT THE TUFT CELLS
ARE DOING?
DO THEY HAVE ANY ROLE IN THAT
PRIMING STEP IN THE CIRCUIT
AMPLIFICATION?
AND AGAIN TO SUMMARIZE QUICKLY
THE ANSWER IS NO.
BY ANY MEASURE TYLER COULD LOOK
AT KIND OF THE IMMUNE
ACTIVATION, WHETHER IT'S IL-13
PRODUCTION, ILC 200, -- ILCs 2,
EARLY OR LATER WHEN WE CAN'T
PROCESS THE INTESTINE, DOESN'T
MATTER FOR THE HYPERPLASIA OF
TUFT CELLS, OF GOBLET CELLS,
LENGTHENING OF INTESTINE SO WE
DON'T THINK IT'S INVOLVED IN THE
PRIMING STEP.
THIS IS SUPPORTED BY EXPERIMENT
WHERE TYLER DELAYED THE DELETION
OF ACETYLCHOLINE PRODUCTION FROM
TUFT CELLS UNTIL DAY 5, AND
STILL FOUND DELAY IN CLEARANCE.
THIS PLACES THE FUNCTION OF TUFT
CELLS ACETYLCHOLINE INTO THE
LAST TWO DAYS OF THIS PARTICULAR
WORM INFECTION.
IS IT WEEP OR SWEEP?
SAND FOR THIS WE WERE LUCKY TO
COLLABORATE WITH TUAN, HERE IN
THE AUDIENCE, ORGAN BATH SYSTEM
SET UP, HE COULD MOUND -- FIRST
EXPAND TUFT CELLS, INJECTING
MICE WITH RECOMBINANT IL-25,
MOUNT INTESTINE IN THE ORGAN
BATH, TRY TO STIMULATE IT.
IN THIS CASE DIRECTLY ACTIVATES
THE TRPM5 CHANNEL.
BUT WHEN THEY DID THAT THERE WAS
NO CHANGE IN THE NUMBER OF PEAKS
OR AMPLITUDE, NO CLEAR EVIDENCE
ACTIVATING TOUGH CELLS ACUTELY
ACTIVATED CONTRACTION.
UNLIKE POSITIVE CONTROL
ACETYLCHOLINE.
TYLER DIDN'T SEE DIFFERENT IN
TRANSIT TIME IN INFECTED MICE
WHETHER OR NOT THERE WAS
ACETYLCHOLINE.
THIS COMPONENT, THE FLUID
SECRETION, INCREASED AS MICE
DEVELOPED HYPERPLASIA FROM DAY 0
TO DAY 7.
AND SO WHAT WE THINK IS THAT
THIS MAY GIVE US SOME
UNDERSTANDING OF AT LEAST SOME
OF THE FUNCTION OF HYPERPLASIA.
ACETYLCHOLINE DOES NOT SIGNAL
FAR ONCE OUTSIDE OF THE CELL,
THERE'S A LOT OF ESTERASES, IN
HOMEOSTATIS, IT IS RARE,
COVERAGE IS SPARSE.
WHAT HYPERPLASIA DOES IS EXPANDS
THE COVERAGE, REDUCES THE PLACES
WHERE THE WORMS CAN HIDE, AND
AMPLIFIES THIS WEEP RESPONSE
WHICH THEN REACHES CRITICAL
LEVEL AROUND AGAIN DAY 7 WHERE
IT CAN CONTRIBUTE TO THE
CLEARANCE.
SO THAT'S HOW WE THINKING ABOUT
SIGNALING TO NEIGHBORING CELLS.
THIS IS THE GRAPHICAL SUMMARY
FROM TYLER'S PAPER, THE IDEA OF
BASOLATERAL RELEASE, HE SHOWED
IN THE USING CHAMBER DRIVING
APICAL SECRETION, PUBLISHED WITH
COMPLEMENTARY WORK.
THEY DIDN'T FIND ANY ROLE IN
THAT SORT OF INITIAL PRIMING.
BUT THEY FOUND THERE'S ALSO
APICAL SECRETION OF THE
ACETYLCHOLINE, THAT CAN ACT
DIRECTLY ON WORMS TO CAUSE SORT
OF SPASTIC PARALYSIS THAT MAY
FURTHER WEAKEN ABILITY TO
COLONIZE INTESTINE.
TWO WAYS TO AID IN EXPULSION OF
WORMS.
ALL RIGHT.
SO, THAT WAS THE TUFT CELL AND
EPITHELIAL PHYSIOLOGY STORY IS
PUBLISHED.
I'M GOING TO SWITCH GEARS TO
TALK ABOUT UNPUBLISHED STORY
WHICH WAS STARTED BY A WONDERFUL
POSTDOC, ALICE STANBURY,
CO-MENTORED BY MARION PEPPER AND
LEFT A YEAR AGO, TYLER HELPED
MOVE THE PROJECT FORWARD FOR
TIME.
BUT THIS CAME FROM WHEN ALOE
JOINED THE LAB, EVERYTHING WE
HAD DONE WAS ON SHORT TIME
SCALES.
REALLY ABOUT INNATE IMMUNITY,
THINGS LIKE THE ION FLUX IN
SECONDS, AND AT MOST A 7-DAY
WORM INFECTION, DRIVEN MOSTLY BY
INNATE LYMPHOID CELLS.
AND SO TYLER -- ALOE WANTED TO
THINK ABOUT, WELL, WHAT ABOUT IN
CHRONIC INFECTION OR
REINFECTION, WHICH REALLY IS THE
MORE RELEVANT TO HUMAN BIOLOGY.
WE'RE COMMONLY CHRONICALLY
INFECTED WITH HELLMET, IN PARTS
OF THE WORLD WHERE THAT'S
COMMON, AND THERE ARE MANY
DEWORMING PROGRAMS THAT
ELIMINATE THEM TEMPORARILY BUT
THERE'S REINFECTION.
THOSE ARE THE KINDS OF THINGS
THAT HAPPEN NATURALLY IN HUMANS.
SOME QUESTIONS ALOE WANTED TO
ADDRESS IS FIRST OF ALL NOW THAT
WE HAVE A SENSE OF HYPERPLASIA
THAT'S IMPORTANT, AS PART OF
EFFECTOR FUNCTION HOW IS THAT
REGULATED IN THESE CHRONIC AND
SECONDARY INFECTIONS, ALSO WHAT
IS THE RELATIVE CONTRIBUTION OF
THESE INNATE LYMPHOID CELLS AND
Th2 CELLS WHICH HAS BEEN A BIT
OF UNRESOLVED QUESTION IN THE
FIELD BECAUSE OF A LACK OF TOOLS
TO REALLY SPECIFICALLY, WE HAVE
A HARD TIME ELIMINATING ILC2s
WITHOUT IMPACTING AND SEPARATING
Th2s.
THE OTHER THING IS WHETHER
THERE'S ANY INTERACTION BETWEEN
TUFT CELLS AND Th2s, AND
SORT OF -- BECAUSE THE QUESTION
WAS -- LET ME BACK UP.
OUR UNDERSTANDING OF THE
FUNCTION FOR TUFT CELLS IN THESE
INNATE PATHWAYS IS THAT
BASICALLY THEY ARE THE EYES OF
ILC2s, THEY NEED THEM TO TELL
THEM THE WORSE IS THERE.
THEY HAVE AN ANTIGEN RECEPTOR,
ONCE YOU HAVE THE SPECIFIC T
CELLS IS THERE ANY NEED FOR TUFT
CELL ANYMORE?
ALL RIGHT.
IN ORDER TO START TO THINK ABOUT
THIS, ALOE TOOK ADVANTAGE OF
THIS DIFFERENT WORM MODEL, I
LEARNED RECENTLY IT'S ACTUALLY
BACERII, VERY DIFFERENT SPECIES,
POLY GYRUS IS IN WILD MICE BUT
WE'RE WORKING WITH BACERRI.
THIS IS A MOUSE-ADAPTED
PARASITE, INAFFECTED THROUGH
ORAL GAVAGE, ESTABLISHED CHRONIC
INFECT OR CAN IF YOU DON'T CLEAR
IT.
LARVAE ENTER AND BURROW INTO THE
SUBMUCOSA WHERE A GRANULOMA
FORMS AROUND THEM, IMMUNE
GRANULOMA, UNTIL 7 OR 8, BECOME
ADULTS, CRAWL BACK OUT AND INTO
THE LUMEN AND SPEND THEIR LIVES.
IF YOU DON'T MANIPULATE, THEY
ARE THERE FOR WEEKS OR MONTHS,
IN B 6 MICE.
BUT YOU CAN CLEAR THEM WITH
BASIC ANTI-HELLMAN FIX, TWO
WEEKS AFTER INFECTION, WAIT FOR
THINGS TO SETTLE DOWN AND DO A
CHALLENGE INFECTION, 28 DAYS
AFTER CLEARANCE.
THEY START INSIST THERE'S A
BIGGER GRANULOMA, AND THE MODEL
IN THE FIELD IS THIS IS THE SITE
OF RESTRICTION, CAN TRIP AND
KILL WORMS, LIMITED RE' MERGENS
INTO THE LUMEN.
WAIT 14 DAYS, DRUG CLEAR, WAIT
28-35, CHALLENGE WITH SECONDARY,
OFTEN LOOK AT WORMS IN THE
INTESTINE 14 DAYS AFTER THAT.
ONE OTHER IMPORTANT TOOL I WANT
TO MENTION BEFORE SHOWING THE
DATA ARE THESE LCR 1 KNOCKOUT
MICE, IL-2 KNOCKOUTS, LUCKY TO
GET THESE FROM JORGE AT PENN,
THEY STARTED BY DOING WHAT THE
HEADY LAB SPECIALIZES IN 3D
GENOME MAPPING IN INNATE
LYMPHOID CELLS, REALIZED THERE
IS THIS DISTAL ENHANCER WHICH
THEY CALLED LCR1 THAT IS OPEN
AND USED ONLY IN ILC2s, OF THE
ID2 GENE, IMPORTANT FOR A LOT OF
LYMPHOCYTE DEVELOPMENT BUT THIS
DISTAL ENHANCER IS ONLY ACTIVE
IN ILC2s, SO WHEN THEY KNOCKED
OUT THAT ENHANCER THEY FOUND
THEY COULD STILL TURN NAIVE T
CELLS INTO Th2 CELLS FINE, NO
PROBLEMS, NO DEFECTS.
BUT THERE'S A BIG DEFECT AND
LOSS OF ILC2s ACROSS TISSUE,
SO IN THE LUNG, FAT, SKIN,
INTESTINE, HOMEOSTATICALLY, WAY,
WAY FEWER ILC2s, A NUMBER
FUNCTION AS KNOCKOUTS AND LET US
DIE -- DISSECT FUNCTION A LITTE
BIT.
ALOE STARTED BY MAPPING TUFT
CELL HYPERPLASIA ACROSS TIME IN
THIS MODEL.
SO WE'RE MEASURING THE NUMBER OF
TUFT CELL PER MILLIMETER CRYPT
VILLUS.
THIS IS THE BASELINE IN B 6
MICE.
INITIALLY NOTHING HAPPENS.
THEN THERE IS A SMALL PEAK OF
THE RESPONSE ON DAY 4, AND THEN
FLATTENS OUT, ANOTHER PEAK DAY
10, 12, 14, AND THEN IT FADES
AGAIN LATER.
THIS IS DIFFERENT, THERE'S A
SINGLE PEAK BEFORE CLEARANCE, AS
SOON AS THE WORMS ARE GONE IT
DROPS.
WE THINK THIS IS BASICALLY THE
DAY 4 RESPONSE IS BASICALLY THE
SENSING OF THE WORMS RIGHT WHEN
THEY PENETRATE INITIALLY AND
TAKES A FEW DAYS FOR THE TUFT
CELL EXPANSION TO HAPPEN AND THE
SECOND IS WHEN THEY REEMERGE
INTO THE INTESTINE.
AND THE RULES THAT GOVERN
HYPERPLASIA SHIFT AS YOU MOVE
THROUGH THIS INFECTION.
SO IN THIS -- AT DAY 4 TIME
POINT, EVERYTHING WORKS THE WAY
WE ALREADY KNEW, YOU NEED
ILC2s, PRCM AND TUFT 25,
WITHOUT THAT NOTHING HAPPENS.
YES, THERE IS STILL CONTRIBUTION
FOR ILC2sA TRPM 5 BUT IT'S NOT
COMPLETE.
ALL OF THESE ARE BACK AT
BASELINE, THERE'S NO RESPONSE AT
ALL.
NOW THERE ARE THESE WAYS FOR
GETTING HYPERPLASIA THAT
FUNCTION OUTSIDE OF THIS
CIRCUIT.
THE OTHER THING IS IF WE BLOCK
RECRUITMENT OF NEW CELLS INTO
THE TISSUE BY AT LEAST
LYMPHOCYTES USING FGY 20 TO
TRACK IN LYMPH NODES YOU ALSO
BLUNT THIS TUFT CELL RESPONSE,
STARTING TO SUGGEST IT'S NOW
REGULATED BY RECRUITED CELLS
LIKE T CELLS AND INDEED IF WE
DEPLETE CD4 POSITIVE CELLS THEY
ARE ABSOLUTELY REQUIRED NOW FOR
THIS HYPERPLASIA.
I DIDN'T SHOW BUT THEY ARE
DISPENSABLE FOR THE INITIAL ONE.
THIS IS ADAPTIVE IMMUNITY,
RIGHT?
YOU'RE SWITCHING FROM INNATE
CELLS TO ADAPTIVE CELLS.
IN SECONDARY INFECTION, CLEARED,
WAITED, REINFECTED, SECOND
INFECTION IS MORE RAPID
HYPERPLASIA, GOES UP
IMMEDIATELY, STAYS HIGH
THROUGHOUT THE COURSE OF
INFECTION.
AND SO NOW WE CAN TRACK WHO IS
MAKING IL-13 AT THESE TIME
POINTS.
WE START HERE AT DAY 2 AFTER
PRIMARY INFECTION, THERE'S LOTS
OF IL-13 POSITIVE CELLS, SMART
13 REPORTER FROM THE LOCKSLY
LAB, BUT ALMOST EXCLUSIVELY
ILC2s.
WE CLEAR, LET THE MICE SIT.
EVERYTHING TURNS BACK OFF.
NOBODY MAKING IL-13.
SECONDARY INFECTION YOU GET NICE
IL-13 RESPONSE BUT EVERYTHING IS
FLIPPED, 90 OR MORE PERCENT OF
THE CELLS ARE T CELLS, ABOUT 40
TIMES MORE T CELLS MAKING 13
THAN ILC2s, INNATE CELLS HAVE
BEEN COMPLETELY SWAMPED.
AND THE RULES AGAIN HAVE
CHANGED.
IF WE'RE NOW LOOKING AGAIN AT
THE SECONDARY INFECTION, NOW
THERE'S NO ROLE AT ALL WE CAN
SEE FOR ILC2s, THE KNOCKOUTS,
HYPERPLASIA IS NORMAL.
STILL T CELL DEPEND, NO LONGER
DEPEND ON CIRCULATING CELLS.
IT HAS ESSENTIALLY REESTABLISHED
A TISSUE INTRINSIC CIRCUIT BUT
REPLACED INNATE ILC2s WITH
RESIDENT Th2s.
IN FACT, THIS RESIDENT CIRCUIT
SEEMS TO BE SUFFICIENT TO CLEAR
THE MICE.
HERE WE'RE EITHER BLOCKING CD4
FOR THE DURATION OF SECONDARY R
BLOCKING CELLS WITH 20.
LET ME WALK YOU THROUGH THIS.
THIS IS A PRIMARY INFECTION.
AND THERE'S NO CLEARANCE OF
WORMS.
WE PUT IN 200, YOU ALWAYS GET
OUT ABOUT 150.
A SECONDARY INFECTION IN
WILDTYPE UNMANIPULATED MOUSE,
THIS IS THE CLEARANCE.
THIS IS THE PROTECTIVE RESPONSE
THAT DEVELOPS.
TOTALLY CD4 DEPENDENT, KNOWN AND
PUBLISHED.
YOU STILL GET REALLY GOOD
CLEARANCE WHEN YOU BLOCK
RECRUITMENT OF OTHER CELLS.
SO SUGGESTING THERE'S REALLY
THIS TISSUE INTRINSIC MECHANISM.
OKAY.
COMING BACK TO THE FIRST
QUESTION THEN HOW IS THE TUFT
CELL HYPERPLASIA REGULATED, WHAT
IS RELEVANT ROLE OF ILC2s AND
Th2s, AS YOU MOVE THROUGH
CHRONIC FRONT PRIMARY INFECTION
INTO SECONDARY THERE ARE
DIFFERENT RULES, REPLACING THE
CIRCUITS WITH Th2s, NOW IN
THE TISSUE, CRITICAL FOR
REGULATING GRANULOMAS, CAN ALSO
REPLACE THE FUNCTION OF THE
ILC2s FOR DRIVING TUFT CELL
HYPERPLASIA.
THIS LEADS US TO THE SECOND
QUESTION.
WHICH IS, NOW THAT YOU'VE PUT
Th2s IN THE CELL, THEY HAVE
AN ANTIGEN RECEPTOR, THERE'S
LOTS OF ANTIGEN AVAILABLE FROM
THESE WORMS AT LEAST INITIALLY
IN THE TISSUE, IS THERE ANY ROLE
ANYMORE FOR TUFT CELLS?
THESE Th2 CELLS COULD FUNCTION
WITHOUT ANY NEED FOR TUFT CELLS.
BUT TURNS OUT THERE DEFINITELY
IS.
SO, THIS IS USING EITHER THE
MICE THAT DON'T HAVE TUFT CELLS,
THE KNOCKOUTS, OR THE MICE THAT
LACK THE CHEMO SENSING CHANNEL
OR DEPOLARIZING CHANNEL TRPM 5,
PRIMARY FUNCTION DOESN'T MATTER
WHETHER HAVE YOU TUFT CELLS, 14
DAYS AFTER PRIMARY YOU HAVE 150,
130 WORMS.
WILDTYPE YOU CLEAR THAT.
BUT MICE THAT DON'T HAVE
SECONDARY INFECTION BUT DON'T
HAVE TUFT CELLS OR TRPM 5
THERE'S BASICALLY NO CLEARANCE
AT ALL BY 14 DAYS AFTER
SECONDARY INFECTION.
AND THIS CLEARANCE ALSO DEPENDS
ON THE KIND OF TUFT CELL
EFFECTORS AND ARMAMENTS.
IL-25 DEFICIENT MICE DON'T
CLEAR.
THE RECEPTOR HAS A ROLE, ILC2s
HAVE A MINIMAL ROLE IN TERMS OF
CLEARANCE OF SECONDARY
INFECTION.
ONE IMPORTANT CAVEAT WITH ALL OF
THESE EXPERIMENTS IS THAT THESE
ARE ALL MICE THAT ARE GLOBAL
CONSTITUENT KNOCKOUTS THAT LACK
THESE THINGS BOTH DURING PRIMARY
INFECTION AND DURING SECONDARY.
SO, ALOE CROSSED OUR IL-25 FLOX
MICE TO INDUCIBLE VILLAIN CRE TO
LEAVE THESE INTACT THROUGH
PRIMARY AND MEMORY AND JUST
BEFORE REINFECTION ADMINISTER TO
TAMOXIFEN TO DELETE IL-25, ONLY
EXPRESSED IN TUFT CELLS IN THE
EPITHELIUM AND SHE COULD
RECAPITULATE CLEARANCE DEFECT SO
CLEARLY TUFT CELLS ARE DOING IN
14 DAYS OF SECONDARY INFECTION
THAT'S REALLY IMPORTANT FOR
ELIMINATING -- I'M SO SORRY --
ELIMINATING WORMS FROM THE
INTESTINE.
THE QUESTION IS WHAT IS IT TUFT
CELLS ARE DOING TO REGULATE THIS
BAKERI CLEARANCE IN SECONDARY
INFECTION.
I TOLD BUT ACETYLCHOLINE
PRODUCTION, THAT COULD BE WHAT
THEY ARE DOING.
IT'S PROBABLY PART BUT NOT THE
ENTIRE EXPLANATION, TYLER REPET
THE CELLS, THIS IS A REAL TREND
TOWARDS DECREASED CLEARANCE IN
THE DEFICIENT MICE.
ONE THING I WILL MENTION IS
WHENEVER WE GIVE MICE TAMOXIFEN
IT HAS SOME BROAD DAMPENING
EFFECT ON TYPE 2 IMMUNITY,
REALLY ANNOYING AND CONFOUNDING.
WE GIVE ALL OUR MICE TAMOXIFEN,
YOU'RE SEEING NOT GREAT
CLEARANCE HERE, WORSE CLEARANCE
WITHOUT THE CHAT.
AGAIN, THIS DOESN'T SEEM TO
EXPLAIN THE REALLY COMPLETE LACK
OF CLEARANCE WE SEE IN, SAY,
TUFT CELL KNOCKOUTS.
ALSO HAS NO EFFECT ON WORM
FITNESS IN TERMS OF FECUNDITY.
GIVEN THE CELLS ARE ESSENTIAL TO
THIS CLEARANCE OF THE SECONDARY
INFECTION ARE TUFT CELLS AND
Th2 CELLS TALKING TO EACH
OTHER?
AND IN ORDER TO THINK ABOUT THIS
I WANT TO TALK ABOUT HOW WE
THOUGHT ABOUT ILC2 ACTIVATION TO
TAKE OUR CUE FROM T CELLS WHERE
WE REALLY UNDERSTAND TCR
SIGNALING, TRANSCRIPTION FACTORS
IT ACTIVATES AND TARGET
CYTOKINES AND Th2 EFFECTOR
CELL, AND THERE'S BEEN BEAUTIFUL
WORK FROM JOHN O'SHEA AT THE NIH
FOR EXAMPLE SHOWING THEY ARE
TRANSCRIPTIONALLY ALMOST THE
SAME CELL.
THEY DON'T HAVE A T-CELL
RECEPTOR, HOW DO THEY ACHIEVE
THAT?
WE PROPOSE BY COMBINING IL-25
FOR NF-kappaB AND AP 1 AND
LEUKOTRIENES, SYNERGY IS POTENT,
AND TURNS OUT IN THE INTESTINE
THE TUFT CELLS CAN PROVIDE BOTH
OF THOSE.
NOW, WE'RE TAKING THAT IDEA AND
PUTTING IT BACK ON THE T CELL
AND SAYING, OKAY, WELL, COULD
YOU DO THE SAME THING IN THE T
CELL AND ELIMINATE -- REDUCE OR
BYPASS NEED FOR T-CELL RECEPTOR,
INNATE-LIKE FUNCTION OF AN
EFFECTOR T CELL.
AND THIS IS NOT A NEW IDEA.
WE WERE HEAVILY INSPIRED BY
FIRST I THINK FOUNDATIONAL WORK
DONE AGAIN HERE BY BILL PAUL
SHOWING THAT IL-33 AND OTHER
CYTOKINES IN THE FAMILY CAN
ACTIVATE EFFECTOR CELLS.
WORK DONE BY THE LOCKSLY LAB
SIMILARLY SHOWING THAT YOU HAVE
THIS SORT OF CHECKPOINT IN THE
TISSUE WHERE T CELLS ENTERING
GET ALARMIN SIGNALS LIKE IL-33
AND IN FAT AT PIERCE LAB, THEY
ARE REGULATED BY IL-33.
BUT WE HAVE FOUND GENERALLY ALSO
FOR ILC2s IT'S REALLY 25
THAT'S WAY MORE IMPORTANT THAN
THE SMALL INTESTINE SO THAT WAS
WHAT WE WANTED TO THINK ABOUT.
TAKING A STEP BACK FIRST THOUGH
WHAT ABOUT THE GENERATION AND
PRIMING OF THE T CELLS IN THE
FIRST PLACE?
IS THERE ANY ROLE FOR TUFT CELLS
OR FOR ILC2s, YOU KNOW, TO BE
HONEST I THOUGHT THERE WOULD BE
A ROLE BECAUSE WE KNOW IN MICE
THAT DON'T HAVE TUFT CELLS
TISSUE RESPONSE IS ALMOST
ABSENT.
BUT DESPITE THAT WE CANNOT FIND
ANY DEFECT IN T CELL PRIMING
LOOKING IN THE LYMPH NODE ON DAY
7 OF MICE THAT HAVE NO TUFT
CELLS, THE PERCENT OF Th2s,
GATA3 POSITIVE, IS THE SAME,
PRODUCTION OF IL-13 IS
UNCHANGED.
AND AGAIN ALSO ADDRESSING THIS
LONGSTANDING QUESTION ABOUT WHAT
IS THE ROLE OF ILC2s IN Th2
PRIMING, AT LEASE USING THIS
KNOCKOUT NO DEFECT, IN ANYTHING
THERE'S MORE.
CONSISTENT WITH THAT WORK WE
DON'T THINK THIS IS A STORY
ABOUT THE MAKING OF EFFECTOR T
CELLS, MIGHT HAVE A ROLE IN
MAINTENANCE.
WE HAVEN'T LOOKED AT THAT.
BUT WE FOCUSED ON THE ACTIVATION
OF THE EFFECTOR RESPONSE.
SO NOW IF YOU LOOK AT THOSE --
IF YOU MAKE MEMORY Th2 CELLS
OUT OF THESE MICE INFECTED,
CLEARED, RESTED, AND EVEN THOUGH
THIS IS A GUT RESTRICTED
INFECTION YOU FIND THESE CELLS
IN LOTS OF TISSUES, ANOTHER
INTERESTING TOPIC.
AND SIMILAR TO WHAT IS REPORTED
THERE'S HIGH EXPRESSION, IN THE
FAT, SOME IN THE LUNG.
NOT SO MUCH IN THE SMALL
INTESTINE, LAMINA PROPRIA HERE,
BUT INSTEAD THEY HAVE IL-25
RECEPTOR, IL7RB SPECIFICALLY,
SOME IN THE MESENTERIC LYMPH
NODES, BUT THE FAT WHICH IS
WRAPPED AROUND THE INTESTINE,
THOSE ARE DIFFERENT Th2s,
EXPRESS A LOT OF IL-33 RECEPTOR
BUT NOT 25 RECEPTOR.
WE DON'T HAVE AN ANTIBODY TO
LOOK AT PROTEIN BUT BY
SEQUENCING IT SEEMS THEY
UPREGULATE TO SOME EXTENT.
SO THE SMALL INTESTINAL PROPRIA
LAMINA, IF WE TAKE THESE CELLS
OUT AND PUT THEM IN A DISH AND
STIMULATE WE CAN DO THAT.
THIS IS POSITIVE CONTROL,
REACTIVATE 70% OF THE Th2s,
AND WHEN YOU COMBINE IL-25 AND
LEUKOTRINES, AND IN VIVO TOO IF
WE MAKE MEMORY CELLS THROUGH
THIS PROTOCOL AND THEN INSTEAD
OF REINFECTING -- WELL, WE
INFECT AS A POSITIVE CONTROL OR
JUST INFECT RECOMBINANT RECOMB,
AFTER TWO DAYS MAKING THE AMOUNT
AFTER EVEN WITH JUST GIVING
RECOMBINANT CYTOKINE.
WHAT ABOUT IF WE ASK THE
OPPOSITE, SUFFICIENCY QUESTION,
IF WE STIMULATE THEM WITH
SIGNALS, WE CAN ACTIVE THEM, DO
YOU NEED TUFT CELLS AND SIGNALS
TO ACTIVATE Th2s, WE STARTED
AT EARLY TIME POINT AND EFFECT
HERE IS MODEST TO NONE.
SO WHEN THERE'S NO TUFT CELLS
THERE IS DEFINITELY DEFECT IN
IL-13 PRODUCTION BY Th2s BUT
DOESN'T SEEM TO RELY ON IL-25.
THIS IS VERY MYSTERIOUS.
WE DON'T REALLY KNOW YET WHAT IT
IS.
DOESN'T SEEM TO BE LEUKOTRIENES
EITHER, AND HYPERPLASIA IS FINE
WITHOUT IL-25 BUT YOU REMEMBER
HOW THIS WORM WORKS?
THIS IS WHEN THE WORM IS IN THE
TISSUE.
WE THINK TUFT CELL MONITOR THE
LUMEN.
T CELLS CAN GET TONS OF ANTIGEN
AND MAY NOT RELY ON TUFT CELLS.
WE WANTED TO REINVESTIGATE
GRANULOMA AND LUMINAL PHASE OF
WORM INFECTION SO THERE'S A LOT
HAPPENING HERE.
WHAT TYLER DID IN THIS
EXPERIMENT WAS COMPARED PRIMARY
GRANULOMA ON DAY 10 AFTER
PRIMARY AND SECONDARY.
THERE ARE EQUAL NUMBERS IN
EITHER CASE.
PRIMARY INFECTION THEY ARE ALL
IN LIKE THE FIRST FIVE
CENTIMETERS OF THE SMALL
INTESTINE, SECONDARY INFECTION
THEY SPREAD OUT MORE WHICH IS
INTERESTING, I HAVE NOTHING MORE
TO SAY ABOUT THAT THOUGH.
WE DON'T UNDERSTAND IT.
AND DEFINITELY THERE ARE WORMS
TRAPPED IN GRANULOMAS IN THE
SECONDSARY INFECTION BUT NOT ALL
OF THEM.
MAJORITY OF THE WORMS ARE
ACTUALLY BACK OUT IN THE LUMEN
AND ESCAPED OUT OF THE
GRANULOMA, NOT HAPPY WORMS.
THEY DON'T MAKE ANY EGGS.
BUT THEY DO GET BACK INTO THE
LUMEN.
AND THERE ARE ACTUALLY EQUAL
NUMBERS OF WORMS AT THIS DAY 10
TIME POINT ACROSS WILD TYPE AND
TUFT CELL KNOCKOUT MICE BUT FOUR
DAYS LATER THAT'S NOT THE CASE.
WILD TYPE MICE WILL HAVE
ELIMINATED WORMS, KNOCKOUTS NOT
AT ALL SUGGESTING THAT THERE'S
ANOTHER CLEARANCE EVENT THAT HAS
TO HAPPEN IN THE LAST DAYS AFTER
THE WORMS COME OUT OF THE
GRANULOMA AND THIS MIGHT BE WHEN
THIS TUFT CELL/T CELL CROSSTALK
COULD BE IMPORTANT.
INDEED WE FIND AGAIN A PARTIAL
BUT MORE CONVINCING ROLE FOR
TUFT CELLS IN REGULATING
Th2s AT LATE DAY 10 TIME
POINT AFTER SECONDARY INFECTION.
THIS IS FIRST LOOKING IN
MESENTERIC LYMPH NODE, SOMEWHAT
FEWER Th2s MAKE LESS I L.
WE WERE ABLE TO GET SECONDARY
INFECTION.
FREQUENCY OF THE CELLS IS NOT
THAT DIFFERENT BUT THE
PRODUCTION OF IL-13 IS DOWN WHEN
YOU DON'T HAVE TUFT CELLS OR
DON'T HAVE IL-25.
DEFINITELY PARTIAL PHENOTYPE BUT
REAL.
AND THEN LASTLY SIMILAR TO WHAT
WE DID WITH THE ACETYLCHOLINE WE
TIMED DELETION, LEFT EVERYTHING
INTACT UNTIL DAY 6 AFTER
SECONDARY INFECTION, AND YOU
AGAIN SEE DEFECT SUGGESTING --
SUPPORTING THE IDEA THERE'S A
ROLE LATE IN INFECTION FOR THE
TUFT CELLS.
OKAY.
SO SUMMARIZING THEN THIS PART,
TUFT CELLS AND ILC2s ARE
DISPENSABLE FOR PRIMING IN THE
MODEL.
IN THE LUMEN THIS SEEMS TO
REQUIRE TUFT CELLS, WE'RE NOT
SAYING THERE'S NO ROLE FOR TCR
BUT THERE'S AN ADDITIVE
IMPORTANT FUNCTION FOR THESE
ALARMENS MADE BY THE TUFT CREST.
ESSENTIALLY IT'S A REWIRING OF
CIRCUIT, TUFT Th2 CIRCUIT AND
WE THINK THIS HAS INTERESTING
IMPLICATIONS, YOU NEED TO
ESTABLISH TISSUE RESIDENT
RESPONSES IF YOU WANT A GOOD
VACCINE, POSSIBLY THROUGH A
PRIME POLL APPROACH.
IF THERE'S MISMATCHED ANTIGEN
TUFT CELLS SEEM TO SENSE
HELMINTHS, MAYBE THEY COULD DO
ACTIVATING OF BYSTANDER
Th2s, DOES THAT HAVE
CONSEQUENCE IN FOOD ALLERGY?
LAST THING I WANT TO SAY IS WE
THINK THIS IS NOT THE WHOLE
STORY SO WE'VE IDENTIFIED
ACETYLCHOLINE, EPITHELIUM,
TALKING TO ILC2s, IL-25
TALKING, COULD BE A RULE FOR
LEUKOTRIENES, WE HAVE REASONS TO
THINK IN SECONDARY INFECTION
MODEL THERE ARE OTHER TARGETS OF
TUFT CELL EFFECTORS.
THERE'S LOTS OF CELLS TO THINK
ABOUT HERE.
NEURONS, MYELOID CELLS, B CELLS,
THOSE ARE THINGS WE'RE JUST
STARTING TO DO.
OKAY.
SO BIG THANK YOU TO THE LAB.
IT'S BEEN WONDERFUL TO WORK WITH
THESE PEOPLE.
MOST OF THE PEOPLE WHO DID THE
WORK I SHOWED YOU TODAY HAVE
MOVED ON.
WE'VE GOT NEW GRADUATE STUDENTS,
I'M REALLY EXCITED TO SEE WHAT
THEY START UP.
LOTS OF FANTASTIC COLLABORATORS.
RIGHT, I WILL SAY WE'VE DONE
REALLY WITH FUNDING THIS YEAR,
WE HAVE A FUNDED POSTDOC
POSITION, $79,000 IN SEATTLE
NOW, I THINK THAT MIGHT BE THE
HIGHEST IN THE COUNTRY, A REALLY
COOL PROGRAM THAT WAS STARTED IN
THE DEPARTMENT THAT PROVIDES --
YOU CAN CHOOSE ACADEMIC OR
INDUSTRY TRACK FOR TRAINING AS A
POSTDOC.
SO LET ME KNOW IF YOU'RE
INTERESTED OR KNOW ANYONE, SEND
ME AN E-MAIL.
THANKS FOR YOUR ATTENTION.
HAPPY TO TAKE QUESTIONS.
[APPLAUSE]
>> THAT WAS WONDERFUL, AS USUAL.
TWO QUESTIONS.
THE FIRST QUESTION WAS TO DO
WITH ACETYLCHOLINE WEEP OR SWEEP
RESPONSE.
WONDERING IF IT APPLIES TO THE
LARGE
LARGE AND SMALL INTESTINE, IF
YOU TRIED TRICURIOUS INFECTION
WHICH AFFECTS LARGE INTESTINE,
WHETHER OR NOT YOU GET THIS PART
OF THE EFFECTOR PATHWAY
ACTIVATION?
>> YEAH.
WE'VE DONE PRELIMINARY
EXPERIMENTS WITH MY LAB MATE AND
NEIGHBOR, AND WORKS ON THIS.
IT'S BEEN CONFUSING, WE'VE DONE
IT THREE TIMES IN TUFT CELL
KNOCKOUTS TWICE, ONCE REQUIRED,
ONCE NOT.
IF YOU STIMULATE YOU GET FLUID
TISSUE RESPONSE TYLER SHOWED IN
COLONIC TISSUE.
BUT WHAT DOES NOT HAPPEN IS
COLON, YOU DO NOT GET
HYPERPLASIA, TO THE SPEND IT
CAN'T BE AMPLIFIED THE SAME WAY.
SO WE'RE NOT QUITE SURE HOW TO
THINK ABOUT THAT.
>> OKAY.
SO THE OTHER QUESTION I HAD WAS
TO DO WITH SECONDARY INFECTION.
AND, YOU KNOW, THE DATA YOU SHOW
ON THE REQUIREMENT FOR CD4 CELLS
AND INNATE CELLS REALLY LOOKS
LIKE IL-4 ACTIVATED MACROPHAGES,
IN THE SENSE THAT, YOU KNOW,
LIKE EARLY ON IN WOUND HEALING
YOU HAVE THIS T CELL INDEPENDENT
ACTIVATION OF MACROPHAGES BUT
LIKE SUSTAINED CHRONIC INFECTION
REQUIRES CD4 POSITIVE, MY
QUESTION HAVE YOU LOOKED AT
MAYBE MACROPHAGES BEING LIKE
THIS KIND OF PART OF THIS
CIRCUIT BETWEEN THE TUFT CELLS
AND THE Th2 CELLS AND, YOU
KNOW, JUST IN TERMS OF LIKE
MAYBE NUMBERS OF THESE ACTIVATED
MACROPHAGES BECAUSE THEY ARE
IMPORTANT IN CLEARANCE.
>> TOTALLY.
YEAH, BASICALLY THE ANSWER IS
NO, WE HAVEN'T DONE MUCH.
ONE THING WE DID WAS USE LYSE M
CRE TO TAKE THE 25 RECEPTOR OFF
MYELOID CELLS, JUST AS ONE --
>> AT THAT POINT I THINK IT'S
THE -- WHAT'S ACTIVATING THOSE
CELLS IS ACTUALLY THE TH 2
CELLS.
>> I AGREE.
WE DIDN'T SEE ANYTHING WHEN WE
DID THAT.
>> YEAH.
>> THE OTHER THINGLY ADMIT WE'VE
HAD TOTAL IL-13 BLINDERS, WE
LOVE TO USE REPORTERS, THAT
MEANS WE'VE GOT TO CROSS THEM
INTO ALL THESE THINGS.
WE'VE DONE EVERYTHING WITH 13
REPORTERS.
WE'RE NOW GEARING UP TO LOOK AND
SEE, IT WOULD BE REALLY
INTERESTING TO ME IF THERE'S A
BIGGER DEPENDENCE ON THE TUFT
CELLS FOR THE IL-4 PRODUCTION
THAN 13 PRODUCTION BY THE
Th2s WHICH THEY DO UNIQUELY,
ILC2s DON'T DO THAT.
IT MIGHT BE TRUE BECAUSE AGAIN
THIS LIKE M FAT SIGNAL FROM THE
LEUKOTRIENES.
TBD.
DO WE GO OVER HERE?
>> A QUESTION ABOUT THE
ACETYLCHOLINE EFFECT, IN SOME
CASES YOU HAVE EFFECTS IN TUFT
CELLS, OTHER ONES YOU DON'T.
BUT ARE THERE OTHER SOURCES OF
ACETYLCHOLINE AND WHAT ABOUT
NERVOUS TISSUE, CAN YOU DO
VAGOTOMY.
>> WE DID A CRUDE ABLATION OF
SENSORY NEURONS, THAT DID NOT
ALTER CLEARANCE.
>> IS THERE ROLE FOR
ACETYLCHOLINE IN DRIVING
DIFFERENT T-CELL RESPONSE, EARLY
OR LATE?
MACROPHAGES DO EXPRESS --
>> THIS NON-NEURONAL
ACETYLCHOLINE IS LIKE A HUGE NEW
FIELD, T CELLS, MACROPHAGES.
WE'VE NOT SEEN A ROLE FOR TUFT
CELL ACETYLCHOLINE BUT NEURONAL
CERTAINLY THAT'S POSSIBLE.
>> CAN YOU JUST BLOCK?
WHAT IF YOU BLOCK DURING A LATE
PHASE, FOR EXAMPLE?
>> WITH LIKE AN ATROPINE?
>> WHY.
>> THE MICE ARE NOT HAPPY.
>> THANK YOU.
>> G-PROTEIN COUPLED RECEPTOR
PATHWAY IS THAT INVOLVED IN
SENSING THE WORMS?
>> WELL, SUCCINATE RECEPTOR
PATHWAY IS NOT.
LIKE A G NET 3 KNOCKOUT MOUSE,
THAT --
>> GUSTISIN.
>> YES, NO SENSING, TOTALLY
NORMAL CLEANS IN SENSING OF THE
WORMS.
>> THAT MOUSE DID HAVE A GUT
PHENOTYPE IF I REMEMBER RIGHTLY,
HYPERINFLAMMATORY IN DSS MODEL.
DIDN'T MAKE IL-13 OR 5, THE
KNOCKOUT, YEAH.
I COULD BE MISREMEMBERING BUT
I'M PRETTY SURE IT DID HAVE GUT
DEFECT.
>> I THINK THERE ARE MULTIPLE G
NET KNOCKOUTS, ONE LINE HAD
SOMETHING, THE OTHER DIDN'T, IF
I REMEMBER.
I DON'T KNOW.
THIS IS LIKE TALKING TO PEOPLE
AT LIKE MONELLE WHO WORKED ON
THESE THINGS.
MEMORY, I THINK THEY DECIDED
THAT WAS NOT.
>> IS THERE MANY ORPHAN GPCRs,
THIS WAS OUR APPROACH TO LOOK
JUST ON TUFT CELLS AND NOT
OTHERS.
FIRST NON-ORPHAN, LIKE TASTE
RECEPTORS WE DON'T SEE ON
INTESTINAL TUFT CELLS, THEY ARE
IN THE AIRWAY FOR SURE.
THERE'S ONE OR TWO, MOST
INTERESTING GPRC 5C, MADE A
KNOCKOUT, NO PHENOTYPE.
YEAH, WE'RE STILL SEARCHING.
>> THANKS.
>> GREAT TALK.
THINKING ABOUT AMPLIFICATION
CIRCUIT, ILCs OR Th2s, I
LIKE THE IDEA OF THE
ACETYLCHOLINE AS LIMITED
DIFFUSION RATE, DO YOU HAVE ANY
SENSE IS THERE A DISADVANTAGE TO
HAVING PARASITE INDUCED LEVELS
OF TUFT CELLS AT HOMEOSTASIS IN
THE ABSENCE OF TYPE 2 INITIATOR
MEANING IF YOU HAVE TOO MANY
AROUND DOES THAT INTERFERE WITH
NORMAL ABSORPTIVE FUNCTION?
>> ZERO CONSEQUENCE.
THIS IS WORK THAT I WAS INVOLVED
IN THE PROJECT, LIKE BEFORE I
LEFT THE LOCKSLY LAB, CHRIS
SNYDER FINISHED IT.
WE MADE THESE MICE, DELETED A
20, THIS BROAD INHIBITOR, OUT OF
ILC2s, IT TOOK THE BRAKES OFF
THE CIRCUIT.
THOSE MICE AS SOON AS PROTEUS
EXPANDED THEY HAVE MASSIVE
HIGHER PLASIA, ZERO HEALTH
CONSEQUENCES, NO WEIGHT
SEQUENCES, PUT THEM IN METABOLIC
CAGES, NO DIFFERENCES, DID
CALORIEMETRY TO ABSORB THE SAME.
INTESTINE WAS 27% LONGER, THE
ONLY DIFFERENCE.
THE IDEA WAS THAT BECAUSE ON
LIKE A PER AREA BASIS THEY HAD
FEWER ABSORBTIVE DEVELOPS,
WITHIN DAYS OF ACTIVATING TYPE 2
IMMUNITY IN THE SMALL INTESTINE
IT GETS 20% LONGER, REALLY COOL,
THE MECHANISMS OF THAT ARE NOT
CLEAR TO ME, YEAH.
>> HI.
SO, I WAS WONDERING ABOUT
THIS -- IN THE SECOND PRIME
MODEL DESCRIBED LIKE INITIAL --
SUSTAINED MORE TUFT CELLS, YOU
SEE MORE TUFT CELLS, DO YOU
THINK SUSTAINED RESPONSES, THE
SAME TUFT CELLS THAT ARE
DIVIDING OR IS IT STEM CELLS?
BECAUSE YOU KIND OF -- WHEN YOU
INTRODUCED THIS IDEA YOU
MENTIONED THIS HAPPENS IN FOUR
DAYS AND GOES BACK TO NORMAL, DO
YOU THINK IT'S THE SAME TUFT
CELLS OR JUST STEM CELL AND TO
BE HONEST I DON'T KNOW HOW YOU
DISSECT THAT.
>> YEAH, EVERYTHING WE'VE DONE
TO LOOK AT TUFT CELL LIFESPAN
SUGGESTS THEY DON'T -- ACTUALLY
JUST IN THE LAST MONTH WE FOUND
EVIDENCE THEY LIVE A LITTLE
LONGER THAN ENTEROCYTES BUT ONLY
A FEW DAYS, IF YOU DON'T KEEP
MAKING NEW ONES THEY ARE GOING
TO BE GONE PRETTY QUICKLY.
SO THERE MUST BE A CONTINUAL
ADDITIONAL PRODUCTION, YEAH,
YEAH.
>> THANK YOU.
>> HI.
GREAT TALK.
I WAS WONDERING IF YOU SEE ANY
ROLE FOR -- IN YOUR RESPONSE OF
THE RESPONSE -- I DON'T KNOW HOW
MANY BASOPHILS THERE ARE.
DO THEY ACCUMULATE DURING THE
INFECTION?
>> YEAH, WE'VE NOT DONE ANY
CHARACTERIZATION OF BASOPHILS IN
THAT MODEL.
OTHERS HAVE.
THE CONCLUSION, THERE'S A ROLE
FOR BASOPHILS IN THE TRICURUS
MODEL, IN THE OTHER MODEL NOBODY
FOUND A ROLE FOR BASOPHILS TO MY
KNOWLEDGE.
>> WONDERFUL, JAKOB.
I LIKE TO ASK BIG QUESTIONS.
>> I THINK TO THINK ABOUT THEM.
>> DID GOD MAKE INTESTINAL TUFT
CELLS TO EXPEL HELMINTHS OR IS
THERE ANOTHER FUNCTION, I WOULD
PUT MONEY ON ANOTHER HOMEOSTATIC
FUNCTION.
SECOND PART, ANN WAS DELVES IN
THE SAME DIRECTION, IS WHAT ARE
THEY REALLY SENSING?
IF IT'S NOT SUCCINATE OR IF IT
IS HELMINTHS THE ONLY THING THEY
REALLY SEE WHAT COULD IT
POSSIBLY BE THEY ARE
RECOGNIZING?
>> OKAY, YOUR BIG QUESTION I
REALLY LIKE THAT ONE.
I'VE THOUGHT ABOUT IT.
WE'VE THOUGHT ABOUT IT.
TOTALLY AGREE WITH YOU.
I DON'T THINK THESE CELLS
EVOLVED FIRST TO SENSE WORMS.
AND MY MOTIVATION FOR THAT IS
GOBLET CELLS.
GOBLET CELLS ARE CRITICAL FOR
THE DEFENSE AGAINST HELMINTHS
BUT I DON'T THINK ANYONE WOULD
ARGUE THEY EVOLVED FOR THAT.
YOU NEED TO MAKE MUCUS FOR
EPITHELIAL MUCOSAL, AND THEY
WERE RECRUITED.
MY BIAS IS TO THINK IT'S SIMILAR
FOR TUFT CELLS, AND IT'S WHY I
LOVE THE PHYSIOLOGY AND FLUID
STORY BECAUSE IT DUST LINK TO
FUNDAMENTAL PHYSIOLOGY OF
MUCOSAL BARRIERS.
IN TUFT CELL KNOCKOUTS THERE'S
NO BIG -- IT'S NOT LIKE THEIR
INTESTINE TRIES OUT.
THESE ARE PATHWAYS THAT ARE
IMPORTANT, A LOT OF BACKUP,
MAYBE THERE'S SOMETHING LIKE
THAT.
BUT I AGREE, I MEAN I THINK,
YEAH, I AGREE I DON'T THINK
THAT'S WHAT THEY EVOLVED FOR
FIRST AND THEY WERE RECRUITED
INTO THAT BECAUSE THEY TURNED
OUT TO BE USEFUL.
WHAT ARE THEY SENSING?
>> THEY PROBABLY WOULDN'T SEE
PARASITES ANYWAY?
>> TISSUES?
EFFECTORS FUNCTIONS SEEM TO BE
CONSERVED BUT SENSING IS
DIVERSIFIED, WE DON'T THINK THEY
SENSE WORMS IN THE AIRWAYS,
SENSING BACTERIA OR IRRITANTS.
WHAT ARE THEY SENSING FROM
WORMS?
YEAH, THIS HAS BEEN THE
CHALLENGE.
WE STILL DON'T KNOW.
WORMS SECRETE A LOT OF STUFF, A
LOT OF CANDIDATES, BUT YEAH.
>> REALLY INTERESTING
PRESENTATION.
THE DID MY Ph.D. WITH CHRIS
ALLEN AT UCSF, I LIKE TO ASK
SMALL QUESTIONS.
JUST WANTED TO GIVE YOU SOME
SPACE TO MAYBE EXPLAIN WHY YOU
ALLERGIES.
WHEN YOU MENTIONED FLUID LOSS
FROM THE CHLORIDE IONS, CHOLERA
TOXIN WHICH WE USE TO INDUCE
FOOD ALLERGY IN MICE, WHETHER
YOU MIGHT HAVE LOOKED AT CHOLERA
TOXIN INFECTION AND DO TUFT
CELLS EXPAND AFTER THAT?
>> THAT WAS A LOT OF SMALL
QUESTIONS.
[LAUGHTER]
SUPER INTERESTING.
YEAH, YOU IDENTIFIED A BIT OF
NARRATIVE FLAW IN MY
PRESENTATION THAT I HIGHLIGHT
ALLERGENS AND DON'T TALK ABOUT
THEM.
I DON'T THINK TUFT CELLS SENSE
ALLERGENS.
THAT'S NOT HOW I THINK OF IT.
BUT WHETHER THEY COULD -- IN THE
WAY THEY CAN TUNE TYPE 2
IMMUNITY AND DO HAVE A ROLE IN
FOOD ALLERGY IS WHAT WE'RE
THINKING ABOUT, WHAT THAT COULD
BE ANTIGEN INDEPENDENT WAY.
SO, YEAH, WE'VE TIRED CHOLERA
TOXIN, DOES NOT EXPAND TUFT
CELLS, AND THAT PRIMING CAN
STILL HAPPEN IN THE ABSENCE OF
TUFT CELLS.
BUT SOME -- WE HAVE SOME
PRELIMINARY EVIDENCE THAT IF
YOU'VE ALREADY ESTABLISHED THE
ALLERGY, THAT TUFT CELLS CAN
EXACERBATE IT.
PERHAPS THROUGH WHAT I'VE
DESCRIBED THROUGH THIS SIGNALING
ON THE Th2s OR OTHER
TARGETS.
DOES THAT ANSWER EVERYTHING?
>> I THINK SO.
THANK YOU.
>> ALL RIGHT.
OKAY.
THANK YOU VERY MUCH.
[APPLAUSE]
[END OF PROGRAM]