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Real Time Genomics for Analyzing Dynamic Cell and Tissue Processes: Inflammation Real Time Genomics for Analyzing Dynamic Cell and Tissue Processes: Inflammation Center for Engineering in Medicine Massachusetts General Hospital Harvard Medical School Boston, MA Center for Engineering in Medicine Massachusetts General Hospital Harvard Medical School Boston, MA Martin L. Yarmush Martin L. Yarmush

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  • Real Time Genomics for Analyzing Dynamic Cell and

    Tissue Processes: Inflammation

    Real Time Genomics for Analyzing Dynamic Cell and

    Tissue Processes: Inflammation

    Center for Engineering in MedicineMassachusetts General Hospital

    Harvard Medical School Boston, MA

    Center for Engineering in MedicineMassachusetts General Hospital

    Harvard Medical School Boston, MA

    Martin L. YarmushMartin L. Yarmush

  • Local InflammationLocal Inflammation

  • Systemic InflammationSystemic InflammationChanges in the host’s systemic

    • energetic profile or metabolic state

    • defensive posture

  • • We have known for over a century that inflammation is present in many disorders: anaphylaxis; environmental diseases (smoke inhalation, asbestos exposure, etc.); rheumatoid arthritis; gout; intestinal diseases; and autoimmune diseases; infections; burns; trauma.

    • We have known for over a century that inflammation is present in many disorders: anaphylaxis; environmental diseases (smoke inhalation, asbestos exposure, etc.); rheumatoid arthritis; gout; intestinal diseases; and autoimmune diseases; infections; burns; trauma.

    Why Study Inflammation?Why Study Inflammation?

  • Traumatic InjuryTraumatic Injury• Trauma, which is defined as an injury caused by a

    physical force, includes the consequences of motor vehicle accidents, falls, drowning, gunshots, fires and burns, and stabbing or other physical assaults.

    • Trauma kills more people between the ages of 1 and 44 than any other disease or illness: – 41 percent of all deaths from ages 1-4 – 46 percent of all deaths from ages 5-14 – 73 percent of all deaths from ages 15-24

    • ~200,000 Americans of all ages die from trauma each year.

    • >2.6 million are hospitalized from traumatic injury at a societal cost estimated at over $260 billion

    • Trauma, which is defined as an injury caused by a physical force, includes the consequences of motor vehicle accidents, falls, drowning, gunshots, fires and burns, and stabbing or other physical assaults.

    • Trauma kills more people between the ages of 1 and 44 than any other disease or illness: – 41 percent of all deaths from ages 1-4 – 46 percent of all deaths from ages 5-14 – 73 percent of all deaths from ages 15-24

    • ~200,000 Americans of all ages die from trauma each year.

    •• >2.6 million are hospitalized from traumatic injury at >2.6 million are hospitalized from traumatic injury at a societal cost estimated at over $260 billiona societal cost estimated at over $260 billion

  • • We have known for over a century that inflammation is present in many disorders: infections; burns; trauma; anaphylaxis; environmental diseases (smoke inhalation, asbestos exposure, etc.); rheumatoid arthritis; gout; intestinal diseases; and autoimmune diseases.

    • In addition, over the past twenty years, many other diseases have been added to this list.

    • We have known for over a century that inflammation is present in many disorders: infections; burns; trauma; anaphylaxis; environmental diseases (smoke inhalation, asbestos exposure, etc.); rheumatoid arthritis; gout; intestinal diseases; and autoimmune diseases.

    • In addition, over the past twenty years, many other diseases have been added to this list.

    Why Study Inflammation?Why Study Inflammation?

  • Model of Chronic Inflammationin the Etiology of Cancer

    Model of Chronic Inflammationin the Etiology of Cancer

    Chronic inflammation

    Replacementhyperproliferation

    Mutation TumorROS/RNS

    ROS/RNS

    Cell damage Promotion

    Initiation

    ↓ apoptosis↑ angiogenesis

    Growthadvantage

  • • We have known for over a century that inflammation is present ininfections; in anaphylaxis; in environmental diseases (smoke inhalation, asbestos exposure, etc.); in rheumatoid arthritis; gout; autoimmune diseases; intestinal diseases; and autoimmune diseases.

    • Over the past twenty years, other diseases have been added to this list.

    • Thus, inflammation is really at the heart of health and disease not only in terms of symptomatology and sequelae, but also in terms of disease etiology.

    • Although selected aspects of inflammation have been studied, no comprehensive quantitative model of the inflammatory process is currently available.

    • Classical engineering analysis which comprises well-defined field equations and boundary value analyses, their prediction and experimental verification, is as yet premature. Identification of the players (i.e. different cell types, genes, proteins) and their dynamics must become an integral and early part of the engineering analysis.

    • We have known for over a century that inflammation is present ininfections; in anaphylaxis; in environmental diseases (smoke inhalation, asbestos exposure, etc.); in rheumatoid arthritis; gout; autoimmune diseases; intestinal diseases; and autoimmune diseases.

    • Over the past twenty years, other diseases have been added to this list.

    • Thus, inflammation is really at the heart of health and disease not only in terms of symptomatology and sequelae, but also in terms of disease etiology.

    • Although selected aspects of inflammation have been studied, no comprehensive quantitative model of the inflammatory process is currently available.

    • Classical engineering analysis which comprises well-defined field equations and boundary value analyses, their prediction and experimental verification, is as yet premature. Identification of the players (i.e. different cell types, genes, proteins) and their dynamics must become an integral and early part of the engineering analysis.

    Why Study Inflammation?Why Study Inflammation?

  • WOUND, INFECTION,

    TUMORglucose, APR

    INFLAMMATORY CELLS

    IL-1β, IL-6, TNFα

    catecholamines, glucocorticoids, glucagon, insulin

    amino acids

    SKELETAL MUSCLE

    IGFBP-1

    NERVOUS SYSTEM

    ENDOCRINE SYSTEM

    Liver Plays A Central RoleLiver Plays A Central Role• A principal target of systemic inflammatory mediators• Supplies necessary components for immediate defense at site of injury• A principal target of systemic inflammatory mediators• Supplies necessary components for immediate defense at site of injury

  • New Physiologic StateNew Physiologic State

    Glucose

    PYR

    Ac-CoAAmino Acids

    Lactate

    Urea

    FA

    UreaCycle

    TCACycle

    KetoneBodies

    Glycogen

    PPP

    Glucose

    PYR

    Ac-CoAAmino Acids

    Lactate

    Urea

    FA

    UreaCycle

    TCACycle

    KetoneBodies

    Glycogen

    PPP

    Hypermetabolism Defensive Posture

  • Systems for StudySystems for Study

    Cell Culture

    Perfused organ

    Specificity & Experimental ControlSpecificity & Experimental Control

    Releva

    nce

    Releva

    nce

    Whole Body

    Animal

  • Hepatocytes in InflammationHepatocytes in Inflammation

    InflammatoryMediators

    Altered Gene andProtein

    Expression

    CHANGES INGENE EXPRESSION

    gp130

    hepatocyte

    Describe the new physiologic state or phenotypeDescribe the new physiologic state or phenotype

  • Multiple Organ Dysfunction SyndromeMultiple Organ Dysfunction Syndrome

    InjuryDays After Injury

    Met

    abol

    ic R

    ate

    Multiple Organ Dysfunction

    Syndrome and Death

    200,000 patients/yr

    1 3 7 14 21

    Sho

    ck

    Res

    usci

    tatio

    n

    200,000 patients/yr

    Systemic Inflammatory Response Syndrome (SIRS)

    400,000 patients/yr

    Basal Metabolic Rate

    400,000 patients/yr

    Infections and other “insults”

    The systemic response to injury has an ebb phase of reduced metabolism for ~1 day followed by a flow phase of hypermetabolism that can last wks-mnthsThe systemic response to injury has an ebb phase of reduced metabolism for ~1 day followed by a flow phase of hypermetabolism that can last wks-mnths

  • • Understand why certain hypermetabolic physiologic states reverse and why some do not

    • Understand how diverse dynamic stimuli are integrated by the cell’s intracellular signaling pathways to establish new physiologic states

    • Develop techniques to characterize the dynamics of the cell response to diverse dynamic stimuli

    • Understand why certain hypermetabolic physiologic states reverse and why some do not

    • Understand how diverse dynamic stimuli are integrated by the cell’s intracellular signaling pathways to establish new physiologic states

    • Develop techniques to characterize the dynamics of the cell response to diverse dynamic stimuli

    Long Term GoalsLong Term Goals

  • Diverse Dynamic StimuliDiverse Dynamic Stimuli

    InflammatoryMediators

    Altered Gene andProtein

    Expression (PHENOTYPE)

    CHANGES INGENE EXPRESSION

    gp130

    hepatocyte

  • Pipetting – Many Inputs• multiple wash steps to remove stimuli• Not well suited for dynamic inputs

    Pipetting – Many Inputs• multiple wash steps to remove stimuli• Not well suited for dynamic inputs

    Classical Methods to Control Extracellular Inputs

    Classical Methods to Control Extracellular Inputs

    Needed: A Parallel Perfusion Culture System

    Many Inputs and Dynamic Inputs

    Perfusion Systems – Dynamic Inputs• Serial and low-throughput• Not well suited for many inputs

    Perfusion Systems – Dynamic Inputs• Serial and low-throughput• Not well suited for many inputs

  • Microfluidic Parallel Perfusion Culture SystemsMicrofluidic Parallel Perfusion Culture Systems

    Microfluidic Cell CultureMicrofluidic Cell Culture

  • Dynamic Intracellular SignalingDynamic Intracellular Signaling

    InflammatoryMediators

    Altered Gene andProtein

    Expression

    CHANGES INGENE EXPRESSION

    gp130

    hepatocyte

  • Calvano, Lowry Nature ‘05

    DNA microarrays

    Microarrays: Output-focused

    Many Genes but Few Conditions

    RT- PCR

    Needed: A Tool to Study 10’s of Genes

    Many Conditions and Time Points

    1000’s of Plates

    Gaudet, Sorger ‘05

    Measuring Gene Expression DynamicsMeasuring Gene Expression Dynamics

  • GFP Fluorescent Living Cell Reporters

    Time

  • Microfluidic Living Cell ArrayMicrofluidic Living Cell Array

    1. GFP-based reporter systems

    2. Microfluidic Living Cell Array

    3. Automated time-lapse microscopy

  • GFP Reporter Cell LinesGFP Reporter Cell LinesGFP Reporter Cell Lines

    • H35, a rat hepatoma cell line• Short half-life (2 h) EGFP as a reporter • A library of plasmids of regulatory

    genes of inflammation

    • H35, a rat hepatoma cell line• Short half-life (2 h) EGFP as a reporter • A library of plasmids of regulatory

    genes of inflammation

    RE RE RE CMVmin EGFP

    Transcription factor binding sequence

    enhanced d2EGFPCMV minimal promoter

    RE

    pd2EGFP

  • Response ElementsResponse ElementsResponse Elements

    • NFκB: nuclear factor κB

    • AP-1: activator protein 1

    • HSE: Heat shock response element

    • GRE: Glucocorticoid response element

    • ISRE: interferon-stimulated response element

    • STAT3/APRF: signal transducer and activator of transcription 3/acute phase response factor

    • C/EBP: CCAAT enhancer binding protein

    • HNF1: hepatocyte nuclear factor 1

    • NFκB: nuclear factor κB

    • AP-1: activator protein 1

    • HSE: Heat shock response element

    • GRE: Glucocorticoid response element

    • ISRE: interferon-stimulated response element

    • STAT3/APRF: signal transducer and activator of transcription 3/acute phase response factor

    • C/EBP: CCAAT enhancer binding protein

    • HNF1: hepatocyte nuclear factor 1

  • IKK

    Caspases

    JNK

    AP-1

    RIPIAP

    TNF-α

    NFκB

    HSF1

    ISRE

    GR

    STAT3IκBα

    IL-1IL-6

    DexIFN

    HSP70

    Jak

    C/EBPERK

    LPS

  • Cloning StrategyCloning StrategyCloning Strategy

    Stimulation

    Expansion

    Negative Sorting

    4.56 %

    55.94 %

    Stimulation

    Stable Transfection

    Positive sorting

  • Cloning StrategyCloning StrategyCloning Strategy

    • Limited dilution for subcloning• Monoclonal screening by FACS & microscopy• Limited dilution for subcloning• Monoclonal screening by FACS & microscopy

    NFκB AP-1

  • 0

    0.05

    0.1

    0.15

    0 5 10 15 20 25

    p65 TransFactor AssayRelative Difference in p65 binding

    treated with +/- 10 ng/mL TNFαHeLad4NFkB_EGFP

    time (hr.)

    0

    0.02

    0.04

    0.06

    0.08

    0.1

    0 5 10 15 20 25

    p50 TransFactor AssayRelative Difference in p65 binding

    treated with +/- 10 ng/mL TNFαHeLa_p50d4NFkB_p50

    time (hr.)

    Characterization: DNA Binding DynamicsCharacterization: DNA Binding Dynamics

  • Characterization: GFP Level DynamicsCharacterization: GFP Level Dynamics

    0

    10

    20

    30

    40

    50

    1

    1.5

    2

    2.5

    3

    3.5

    4

    4.5

    5

    0 5 10 15 20 25

    d4EGFP Fluorescence and Protein following stimulation with 10 ng/mL TNFα

    relative difference M2%

    10 ng/mL0 ng/mL

    time (hr.)

    FAC

    S EG

    FP F

    luor

    esce

    nce

    (rel

    ativ

    e di

    ffere

    nce

    in m

    2%)

    Western B

    lot Analysis

    (relative difference in EG

    FP protein)TNFα10 ng/mL

  • Characterization: Cell Cycle DependenceCharacterization: Cell Cycle Dependence

    Cell Synchronization Improves Homogeneity of Response

  • Characterization: Response to PulsesCharacterization: Response to PulsesNFκB Reporter Response to 2hr Pulse of 10ng/mL TNF-α

    Time (hr)

    0 10 20 30 40

    Nor

    mal

    ized

    Flu

    ores

    cenc

    e In

    tens

    ity

    0.0

    0.5

    1.0

    1.5

    2.0

    2.5

    TNF-α

    Reporter Fluorescence

    Destabilized GFP enables transient response monitoring

  • Reporter Responses have Different KineticsReporter Responses have Different Kinetics

    0.00

    0.20

    0.40

    0.60

    0.80

    1.00

    1.20

    0 2 4 6 8 10 12 14 16 18

    Stimulation Time (hour)

    Nor

    mal

    ized

    GFP

    Exp

    ress

    ion

    NFκBAP-1HSEGREISRESTAT3

    Characterization: GFP in Different ClonesCharacterization: GFP in Different Clones

  • Summary

    Time

    • NFκB

    • AP-1

    • HSE

    • GRE

    • ISRE

    • STAT3/APRF

    • C/EBP

    • HNF1

    Plan: Increase Library to 50-100 different clones

  • Microfluidic Living Cell ArrayMicrofluidic Living Cell Array

    1. GFP-based reporter systems

    2. Microfluidic Living Cell Array

    3. Automated time-lapse microscopy

  • Microfluidic Bioreactor FabricationMicrofluidic Bioreactor Fabrication

    Silicon Master Mold:Photoresist is spin coated and exposed through high-resolution photomask

    Polymer Replicas:Cast, cure, and peel PDMS silicone elastomer

    Fluidic Assembly: Drill holes, bond to glass substrate, and autoclave sterilize

  • Microfluidic Cell CultureMicrofluidic Cell Culture

    Surface Modification:Fibronectin is physisorbedand bubbles purged

    Cell Seeding:Inject high concentration cell suspensions

    Long-term Culture:Maintain cells by continuous-flow (gravity or syringe pump) or discrete medium changes (using syringe)

  • Monitor GFP Reporter DynamicsMonitor GFP Reporter Dynamics

    Time

  • Results (IL-1 Stimulation)

    NFκB

    ISRE

    STAT3

    HSE

  • 0

    0.2

    0.4

    0.6

    0.8

    1

    1.2

    0 5 10 15 20

    Time (hrs)

    Nor

    mal

    ized

    Inte

    nsity

    NFkB MicroscopyGRE MicroscopyGRE FACSNFkB FACS

    0

    10

    20

    30

    40

    50

    60

    70

    80

    0 200 400 600 800 1000

    Intensity of Green Fluoresence

    Num

    ber o

    f Cel

    ls

    Control2 hr4 hr6 hr8 hr13.5 hr18 hr25 hr

    0

    10

    20

    30

    40

    50

    60

    70

    0 200 400 600 800 1000 1200

    Intensity of Green Flourescence

    Num

    ber o

    f Cel

    ls

    control

    5 hr

    8 hr

    18 hr

    GRE

    NFκB

    Characterization: FACS and LCACharacterization: FACS and LCA

  • Characterization: LCA vs CultureCharacterization: LCA vs Culture

    Comparison of Microfluidic and Culture Plastic Responses

    Time (h)

    0 2 4 6 8 10 12

    Nor

    mal

    ized

    Flu

    ores

    cenc

    e

    0.0

    0.2

    0.4

    0.6

    0.8

    1.0Dynamic LCAStatic Dish

  • SummarySummary

    • We can reproducibly perform microfluidiccell culture

    • Image dynamic GFP reporting

    • Results comparable to traditional methods (FACS and Cell Culture)

  • Multiple Inputs/OutputsMultiple Inputs/Outputs

  • Microfluidic Living Cell ArrayMicrofluidic Living Cell Array• 50mm deep channels

    • 256 cell culture chambers (

  • Yellow: Cell Culture Channels

    Red and Green: Valve Control Channels

    Microfluidic Living Cell ArrayMicrofluidic Living Cell Array

  • Microfluidic ValvesMicrofluidic Valves

    Valve Closed

    PDMS

    Valve control channel

    PDMS

    Apply negative pressure

    Valve Open

  • Cell SeedingCell Seeding

  • Cell Seeding in RowsCell Seeding in Rows

    Valves Prevent Cross-talk during Cell Seeding

  • Cytokine Stimulation in ColumnsCytokine Stimulation in Columns

    Valves Prevent Cross-talk during Cell Stimulation

  • Cell Lines Grow to Confluency in the ArrayCell Lines Grow to Confluency in the Array

  • Seeding Outlet

    Stimulus Outlet

    8 Clones8 Stimuli4 Replicates24 Time Points>5000 stpm/day

    Valve Control 1

    Valve Control 2

    Multiple Cell Types

    Multiple Soluble Stimuli

  • Nontransfected

    NFκB

    AP-1

    STAT3

    ISRE

    GRE

    HSE

    Constitutive GFP

    MediumTNF-α

    IL-1β IL-6 INFγ Dex

    TNF+IL1+IL6

    TNF+IL1+IL6+Dex

    Response to Inflammatory MediatorsResponse to Inflammatory Mediators

  • Dynamic Gene ExpressionDynamic Gene Expression

    NF-kappaB Response to TNF-a

    0

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6

    0.7

    0.8

    0.9

    0 5 10 15 20 25 30 35

    Tim e (hour)

    Nor

    mal

    ized

    Flu

    ores

    cenc

    e (R

    FU)

  • IL-1 Stimulation

    NFκB

    ISRE

    STAT3

    HSE

  • TNF-α-Induced DynamicsTNF-α-Induced Dynamics

    STAT3HSE

    TNF-α

    NFκB

  • Time (hours)

    0 10 20 30

    Nor

    mal

    ized

    Inte

    nsity

    0.0

    0.2

    0.4

    0.6

    0.8

    1.0

    NFκBSTAT3HSE

    TNF-α-Induced DynamicsTNF-α-Induced DynamicsNFκB

    STAT3

    HSE

    Time

    STAT3HSE

    TNF-α

    IKK JAKJNK

    ERK

    IL-6

    NFκB

    ?? ?

  • HSE Reporter Dynamics are Stimulus-dependentHSE Reporter Dynamics are Stimulus-dependent

    HSE

    TNF-α IL-6IL-1

  • Time (hours)

    0 10 20 30N

    orm

    aliz

    ed In

    tens

    ities

    0.0

    0.2

    0.4

    0.6

    0.8

    1.0

    TNF-αIL-1IFNγTNF-α/IL-1/IL-6TNF-α/IL-1/IL-6/Dex

    HSE Reporter Dynamics are Stimulus-DependentHSE Reporter Dynamics are Stimulus-Dependent

    TNF-α

    IL-1

    IFNγ

    TNF-αIL-1 IL-6

    TNF-αIL-1 IL-6 Dex HSE

    TNF-α IL-6IL-1

  • Dynamic Inputs

    Neural Synapse

    Endocrine HormonesR&D Systems Toner, Mitchell ‘03

    Inflammation

    Therapeutics

  • Human LPS Model

    Cell

    LPS

    Gram-negativebacteria

    LBP

    TLR-4

    Cytokineexpression

    Cell

    LPS

    Gram-negativebacteria

    LPS

    Gram-negativebacteria

    LPS

    Gram-negativebacteria

    Gram-negativebacteria

    LBPLBP

    TLR-4TLR-4

    Cytokineexpression

  • Concentration ControlConcentration ControlConcentration Control

    Time

    Con

    cent

    ratio

    n

    Channel Number

    1 2 3 4 5 6 7 8

    [TN

    F-α

    ] (ng

    /ml)

    0

    2

    4

    6

    8

    10

    12

  • NFκB Reporter Response to TNF-α Concentration

    Time (h)0 2 4 6 8 10 12

    Ave

    rage

    Inte

    nsity

    per

    Cel

    l (A

    FU)

    0.0

    0.2

    0.4

    0.6

    0.8

    1.0

    1.2

    1.4

    1.6

    1.8

    2.010.00 ng/ml9.04 ng/ml7.24 ng/ml5.06 ng/ml2.85 ng/ml1.39 ng/ml0.36 ng/ml0 ng/ml

    Dose Response of NFκB ActivationDose Response of Dose Response of NFNFκκBB ActivationActivation

  • Control PatternsControl PatternsControl Patterns

    α

    time

    θ1

    θ2

    θ3

    θ4

    Duration Control

    Transient Cytokine StressTransient Cytokine Stress

    Recovery Period Control

    α

    time

    θ1

    θ2

    θ3

    θ4

    Heat Shock ProtectionHeat Shock Protection

    α

    time

    Period

    f

    2f

    4f

    8f

    θ1

    θ2

    θ3

    θ4

    Frequency Control

    Hormonal ControlHormonal Control

  • QMedium

    QMediumQStimulus

    Waste

    ΔP

    Time

    ΔTθi

    Time

    Time

    Cell Visualization Chamber

    Stimulus

    Stimulus Medium

    QQ Q

    χ ≡+

    ii

    Stimulus

    cc

    θ ≡

    Increasing χ

    Duration Control: Flow-encoded SwitchingDuration Control: Duration Control: Flow-encoded Switching

  • Weeks vs Hours

    Transient Cytokine StressTransient Cytokine StressQMediumQStimulus

    Waste

    χ

    Time

    θ1

    θ20Time (hr)

    0 2 4 6 8 10 12 14 16-0.05

    0.00

    0.05

    0.10

    0.15

    0.20

    0.25

    0.300 min15 min20 min25 min40 min50 min55 min

    2 hr 5 hr 8 hr 11 hr 20 hr Time

    Duration of TNF-α Exposure (min)

    0 10 20 30 40 50 60 70N

    orm

    aliz

    ed N

    F κB

    Act

    ivat

    ion

    Leve

    l0.0

    0.2

    0.4

    0.6

    0.8

    1.0

    1.2

    MicrofluidicHoffman

  • Simultaneous Concentration & Duration ControlSimultaneous Concentration & Duration ControlSimultaneous Concentration & Duration Control

    Duration

    Concentration

    M

    M

  • MICROFLUIDICS TO CONTROL STIMULI

    DYNAMIC GENE EXPRESSION VIA CELL REPORTERS

    CELLULAR RESPONSES DURING INFLAMMATION

    Can we explore this in the context of disease?

  • Hepatic Steatosis: “Fatty Liver”Hepatic Steatosis: “Fatty Liver”

    • Nonalcoholic Fatty Liver Disease or NAFLD: 20% – association w/Metabolic Syndrome and Obesity

    • Steatosis ↑ susceptibility to subsequent injury

    • “Second Hits” (e.g. ischemia) can lead to chronic inflammation and nonalcoholic steatohepatitis or NASH: 2-3%

    • Chronic inflammation in the liver can progress to cirrhosis and hepatocellular carcinoma

  • Hepatic Steatosis: “Fatty Liver”Hepatic Steatosis: “Fatty Liver”

    Hepatosteatosisw/inflammatory infiltrate

    Perivenular fibrosis

    Hepatic Inflammation is Complex and Dynamic

    Fatty ChangeNormal Liver

  • Reporter Cells Become SteatoticReporter Cells Become Steatotic

    Control Medium Fatty Acid and Hormone Supplementation

  • Fatty Acid Uptake in Reporter CellsFatty Acid Uptake in Reporter Cells

    0.0

    0.4

    0.8

    1.2

    1.6

    2.0

    Control Oleic Acid (2 mM) Oleic Acid (4 mM)

    FFA

    (mM

    )

    FFA Decrease

    Nile Red Staining 0.00

    0.02

    0.04

    0.06

    0.08

    0.10

    0.12

    0.14

    Control Oleic Acid (2 mM) Oleic Acid (4 mM)

    Trig

    lyce

    rides

    (mg/

    ml)

    Triglycerides

    FFA Uptake

    Triglyceride Content

  • Responses in Steatotic NFκB Reporters

    Decreased Basal Activity Decreased TNF-a ResponseDecreased IL-6 Response

    • Infected cells, cells metabolizing toxins or drugs

    • Cells in different cell cycle positions, cells fed different diets

  • Hepatocytes Are Not Alone

    Dynamic Tissue MicrosystemsMicroscale Models of Disease

  • Automated Stage 37°C & CO2 Control

    rsGFP YFP CFP PhaseMulti-parameter Detection High Content Screening (HCS)

    Dynamic Tissue Microsystems

    Disease Process Fingerprinting

    Dynamic Clustering

    Mathematical Modeling

    time

    Experiment

    Valve and Pump Control

    Complex System Identification

    •Integrated Microfluidics•Gene Expression Monitoring•100’s of Parallel Experiments•Study Dynamics of Disease Processes•Drug and Toxin Testing

    Stimuli ResponseFunctional Tissue UnitSi(t) Rj(t)

    Steroid/Drug metabolismCholesterol breakdownTriglyceride breakdownCholesterol biosynthesisFatty acid biosynthesisGlycolysisFatty acid biosynthesisBile acid synthesis

    Fatty acid transportFatty acid beta oxidation

    Heme biosynthesisCholesterol importFatty acid import

    12

    3

    4

    5

    6

    7

    •Control Response with Therapeutics

    Drug or Nutrition

    fluor

    esce

    nt s

    igna

    l

    Genes

    Inducers

    time

    kCCDdtdC

    −∇= 2

  • Applicable to Various TissuesInputs Functional

    Tissue UnitOutputs

    Mechanical – Pressure, Shear Stress, Tensile Resistance

    Chemical – Neurohormonal, Cytokines, Oxygenation

    General - Morphology, Cell Shape, Proliferation, Migration, Apoptosis

    Cell-Specific Function - Gene Expression, Protein Interactions, Protein Secretion

    Bone Neurons

    Skin Pancreas

    Muscle Fibers

    Liver

  • Linearized Pancreatic IsletsLinearized Pancreatic Islets

    δ Cells

    Islet

    β CellsArteriole Venule

    Microfabricated bioreactor

    α Cells

  • Tissue AssemblyTissue AssemblyInputs Functional

    Tissue UnitOutputs

    Mechanical – Pressure, Shear, Tensile Resistance

    Chemical – Neurohormonal, Cytokines, Oxygenation

    General - Morphology, Cell Shape, Proliferation, Migration, Apoptosis

    Cell-Specific Function - Gene Expression, Protein Interactions, Protein SecretionCellular – Neutrophils,T Cells

  • Layered Structure

    +Collagen

    +

    Day 4; separation distance: ~ 150 µm

  • VEGF

    HIF1α

    HIF1β

    Hypoxia

    HIF1

    HRE

    5’

    3’

    VEGF R

    ICAM-1

    VCAM-1E-Selectin

    VEGF

    NFkBNFkB

    Hepatocytes-Endothelial Cell Signaling

  • 1. Ischemia

    2. Hepatocyte HIF-1α activation

    3. VEGF expression and secretion

    4. Endothelial Cell NFkB activation

    5. ICAM expression

    6. Reperfusion

    7. Neutrophil Capture

    ISCHEMIA REPERFUSION

    Time

  • MICROFLUIDIC ARRAYS

    STIMULUS CONTROL

    GFP REPORTER LIBRARY

    DYNAMIC GENE EXPRESSION

    DYNAMIC RESPONSES TO INFLAMMATORY CYTOKINES

    DISEASE DYNAMICS

    STEATOSIS AND I/R

  • • Use the LCA and DTM to understand the dynamics of the cell signaling response to diverse dynamic stimuli

    • Understand how diverse dynamic stimuli are integrated by the cell’s intracellular signaling pathways to establish a new physiologic state

    • Make headway in understanding the nature of reversible versus non-reversible physiologic states

    • Find collaborators with interesting problems

    • Use the LCA and DTM to understand the dynamics of the cell signaling response to diverse dynamic stimuli

    • Understand how diverse dynamic stimuli are integrated by the cell’s intracellular signaling pathways to establish a new physiologic state

    • Make headway in understanding the nature of reversible versus non-reversible physiologic states

    • Find collaborators with interesting problems

    Future DirectionsFuture Directions

  • AcknowledgementsAcknowledgements

    FUNDING

    NIH BRP AI063795 (Real Time Genomics) NIH P41 EB002503 (Dynamic Tissue Microsystems)

    INVESTIGATORS

    Kevin King, Sihong Wang, Deanna Thompson, Arul Jayaraman, Ken Weider, Daniel Irimia, Octavio Hurtado, Amol Janorkar, Rohit Jindal, Koby Nahmias, Zak Megeed, Mehmet Toner, Jeff Morgan

    Real Time Genomics for Analyzing Dynamic Cell and Tissue Processes: InflammationLocal InflammationSystemic InflammationTraumatic Injury �Model of Chronic Inflammation�in the Etiology of CancerNew Physiologic StateSystems for StudyHepatocytes in InflammationMultiple Organ Dysfunction SyndromeLong Term GoalsDiverse Dynamic StimuliDynamic Intracellular SignalingGFP Reporter Cell LinesResponse ElementsCloning StrategyCloning Strategy Characterization: Cell Cycle DependenceCharacterization: Response to PulsesReporter Responses have Different KineticsMicrofluidic Bioreactor FabricationMicrofluidic Cell CultureMonitor GFP Reporter DynamicsResults (IL-1 Stimulation)Characterization: LCA vs Culture Microfluidic Living Cell ArrayMicrofluidic ValvesCell SeedingCell Seeding in RowsCytokine Stimulation in ColumnsIL-1 StimulationDynamic InputsHuman LPS ModelHepatic Steatosis: “Fatty Liver”Hepatic Steatosis: “Fatty Liver”Reporter Cells Become SteatoticFatty Acid Uptake in Reporter CellsResponses in Steatotic NFkB ReportersHepatocytes Are Not AloneApplicable to Various TissuesLayered Structure Hepatocytes-Endothelial Cell SignalingFuture Directions