DEBATE

David Baker- For

Heinz Weindl-Against

The Key Pathogenic Cell in MS is a B cell

and is Independent of Antigen-Presentation to T cells

To B or Not T-B, that is the Question?

AT THE LIMITS-MULTIPLE SCLEROSIS 2017

B CELLS ARE AN ACCOMPLICE

T CELLS ARE FACILITATORS

THE IMPORTANT PATHOGENIC CELL IN MS

VICTIM: OLIGODENTROCYTE HAS BEEN MURDERED

B CELL

MEMORY B CELLS ARE GUILTY

T CELLS ARE GUILTY

INFLAMMATORY PENUMBRA IN MS

MYELIN = BROWN

DEMYELINATION

PERIVASCULAR

LESION

RELAPSING MS

BIOLOGY OF MULTIPLE SCLEROSIS

Myelin=brown stainOligodendrocytes do not express MHC class II in vivo

ANTIBODY

CYTOKINE

CELL

HYPOXIA

MS is a T cell-mediatedProblem!

MS is a B cell-mediatedProblem!

Animal Models

Myelin-ReactiveT cells in MS

Dogma

Biology &Available Data

Response to TherapyTreatments

EAE is T cell Mediated!but, Animals Don’t Get MS

Healthy People Respond to the Same Antigens.

Myelin-immunotherapy = FAILED

All active treatmentstarget B cells

Cir

cum

stan

tial

Evid

en

ce

AT THE LIMITS-MULTIPLE SCLEROSIS 2017

To B or Not T-B, that is the Question?

RESPONSE TO THERAPY

If MS is T Cell-Mediated, Why Does Ocrelizumab/Rituximab Work?

• Block B Cell Cytokines & Products

• Block Antigen-Presentation

Why evolve an extra APC Network?

• Block B Cell Follicles (& Pathogenic Antibodies)

Therapeutic Antibodies have very poor CNS penetration

Trophic Support-Cytotoxicity

DMT block peripheral Immune-Response to block Lesion formation

Minor 5-20% T cells Population Important

• Block Pathogenic CD20 T Cells

Is their critical B cell APC function In vivo?

CD4 T cell depletion = FAILEDMarked CD8 depletion (Dimethyl fumarate) = Modest

(DMF has modest depletion of B cells)

To B or Not T-B, that is the Question?

Inebilizumab (anti-CD19) inhibits MS lesionAgius et al. 2017 Mult Scler epub

T CELL SPECIFIC IMMUNOTHERAPY IN MS = FAILED

• CD4 T CELL (~70%) DEPLETION WITH cM-T412 MARGINAL EFFECT- PERCEPTION = FAILED

• Th1 (IL-12/IL-23) T CELL INHIBITION WITH USTEKINUMAB-PERCEPTION = FAILED

• Th17 (IL-17) T CELL INHIBITION WITH SECUKINUMAB MARGINAL EFFECT-PERCEPTION = FAILED

B CELL-DEPENDENT EAE = RUBBISH EAEIT IS SUBOPTIMIZED…TO MAKE ANTIGEN PRESENTATION IMPORTANT

B CELL-DEPENDENT EAE = SUBOPTIMIZED EAE

• Disease Resistant Strain used• Weak Immunogen for Strain• Processing requiring antigen• Low severityTO MAKE ANTIGEN PRESENTATION BY B CELLS APPEAR IMPORTANT

UCL-INSTITUTE OF NEUROLOGYQueen SquareUCL-INSTITUTE OF NEUROLOGYQueen SquareUCL-INSTITUTE OF NEUROLOGYQueen Square

MULTIPLE SCLEROSIS: IS A CD4 Th17 T CELL-MEDIATED DISEASE?

RESPONSE TO THERAPY

B CELL SPECIFIC IMMUNOTHERAPY IN EAE = FAILED/MARGINAL

75% T cell Depletion

Sefia E et al. MSARDS 2017

B cell Knockout

wildtype

Kuerten S et al. J Neuroimmunol.

2006 177:99-111

B cell Depletion

T CELL SPECIFIC IMMUNOTHERAPY IN MS = FAILED

• CD4 T CELL (~70%) DEPLETION WITH cM-T412 MARGINAL EFFECT- PERCEPTION = FAILED

• Th1 (IL-12/IL-23) T CELL INHIBITION WITH USTEKINUMAB-PERCEPTION = FAILED

• Th17 (IL-17) T CELL INHIBITION WITH SECUKINUMAB MARGINAL EFFECT-PERCEPTION = FAILED

UCL-INSTITUTE OF NEUROLOGYQueen SquareUCL-INSTITUTE OF NEUROLOGYQueen SquareUCL-INSTITUTE OF NEUROLOGYQueen Square

MULTIPLE SCLEROSIS: IS A CD4 Th17 T CELL-MEDIATED DISEASE?

Time Post-Induction (Days)

7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

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50

60

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100Vehicle

CD4d mAb

CD8d mAb

CD20d mAb

Anti-CD20 in EAE does not work or has a marginal effect, unless it depletes CD4 T cells.

RESPONSE TO THERAPY

B CELL SPECIFIC IMMUNOTHERAPY IN EAE = FAILED/MARGINAL

75% T cell Depletion

Sefia E et al. MSARDS 2017

Sefia E et al. MSARDS 2017

B cell Depletion

Plasma cellCD19-, CD20-

CD27+,CD38+, CD138+

CD8 memory

CD19+ B CELLS ARE NOT A SINGLE SUBSET

CD4 naive CD4 memory

Th1/Th17

CD8 Naive

CD8 cytotoxicCD8 suppressor

CD4 T regulatory cell

Tr1 regulatory cell

CD19+B cell

T Cell Biologists World View of B Cell Biology

BLOOD

Memory Cell(Guilty in MS)

CD19+, CD27+Unswitched

IgD+

CD19+, CD27+Class switched

IgD-

PlasmablastCD19+, CD20-

CD27+,CD38+

ImmatureCD19+, CD20+

CD27-,CD38+, CD10+

Pre-B CellsCD19+, CD20+

Plasma cellCD19-, CD20-

CD27+,CD38+, CD138+

BONE MARROW

Germinal Centre CellCD19+, CD20+

CD27+, CD269+

LYMPHOIDTISSUE

Primary Follicle Cortex (B cell Area)Secondary

Follicle

T cell Area

FollicularDendritic

Cell

Pro-B CellsCD19-/+, CD20+, CD34+

Naïve/MatureCD19+, CD20+

CD27-,CD38+, CD10-

Regulatory CellCD19+, CD20+CD5+, CD24+

CD19+ B CELLS ARE NOT A SINGLE SUBSET

CD19+, CD27+Class-Switched

IgD-Germinal

Centre CellCD19+,CD20+

CD27+,CD269+

BLOOD

Memory Cell(Guilty in MS)

CD19+, CD27+Unswitched

IgD+

PlasmablastCD19+, CD20-

CD27+,CD38+

Naïve/MatureCD19+, CD20+

CD27-,CD38+, CD10-

ImmatureCD19+, CD20+

CD27-,CD38+, CD10+

Pre-B CellsCD19+, CD20+

BONE MARROW

CD34+ stem Cell

HUMAN B CELLS

Pro-B CellsCD19-/+, CD20-

CD34+

BLOOD

LYMPHOID TISSUE

Plasma cellCD19-, CD20-

CD27+,CD38+, CD138+

Time Post-Administration (Months)

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Immatute B cellsCD19 B cells

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Mature

Naive B cells

Time Post-Administration (Months)

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Memory B cells

Alemtuzumab Targets memory B cells

overshoot

overshoot

MEMORY B CELLS IN MS-THERAPY

Baker D et al. JAMA Neurol. 2017;74:961.

Environment for Secondary B cell Autoimmunities (about 50% at 5 Years)

Time Post-Administration (Months)

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Immatute B cellsCD19 B cells

Time Post-Administration (Months)

0 3 6 9 12 15 18 21 24

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B

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-100

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-20

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40

60

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Mature

Naive B cells

Time Post-Administration (Months)

0 3 6 9 12 15 18 21 24

Mea

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Memory B cells

Alemtuzumab Targets memory B cells

overshoot

overshoot

MEMORY B CELLS IN MS-THERAPY

Baker D et al. JAMA Neurol. 2017;74:961.

Alemtuzumab hCD52 Tgmice kills by ADCC-needs both antibody & natural killer cells/ PMN to kill. (Hu et al. 2009)

Bone marrowNot purged

Environment for Secondary B cell Autoimmunities (about 50% at 5 Years)

MS Treatment Memory B cells in the

Blood

Availability of B cells to

enter CNS

Relapse Rate/

MRI Lesions

Glatiramer acetate

Beta Interferon

Dimethyl fumarate

Mitoxantrone

Fingolimod

Natalizumab

Alemtuzumab

Daclizumab*

Rituximab

Atacicept*

Infliximab*

HSCT

Cladribine

Reduced

Reduced

Reduced

Reduced

Reduced

Increased

Reduced

Reduced*

Reduced

Increased*

Increased*

Reduced

Reduced

Decreased

Decreased

Decreased

Decreased

Decreased

Decreased

Decreased

Decreased*

Decreased

Increased*

Increased*

Decreased

Decreased

Decreased

Decreased

Decreased

Decreased

Decreased

Decreased

Decreased

Decreased

Decreased

Increased

Increased

Decreased

Decreased

* Non-MS data

Loss of B memory Cell function in Efficacious Treatments

MEMORY B CELLS IN MS-THERAPY

Baker D et al. EBioMedicine 2017; 16:41.

Mitoxantrone

FingolimodBeta Interferon Hierarchy of Responsiveness

Loss of B memory Cell function in Efficacious Treatments

Dooley J et al. Neurology N2 2016 3 (e240).Baker D et al. EBioMedicine 2017; 16:41.

MEMORY B CELLS IN MS-THERAPY

NatalizumabLoss of B memory Cell function in Efficacious Treatments

MEMORY B CELLS IN MS-THERAPY

CD19+, CD27+ B Memory

Anti-CD20

Ocrelizumab Phase II extension (Baker et al EbioMedicine 2017; 16:41)

Palanichamy A et al. J Immunol. 2014; 193:580

6 months

1 year

Loss of B memory Cell function in Efficacious Treatments

MEMORY B CELLS IN MS-THERAPY

Anti-CD20

Ocrelizumab Phase II extension (Baker et al EbioMedicine 2017; 16:41)

Palanichamy A et al. J Immunol. 2014; 193:580

6 months

1 year

Induction therapy potential

Developmental Repopulation of B cells is Slow

in Western Europe

Cla

ss s

wit

ched

MEMORY B CELLS IN MS-AETIOLOGY

Duchamap et al. Immun Inflamm 2014:2:131

Absolute NumbersPercentages

Induction therapy using CD20-B cell depletion in non-MS autoimmune

________________________________________________________________________________Total Memory B cells Class switched memory B cells

________________________________________________________________________________Healthy Control 30.5 ± 6.9%; P = 0.001 18.3 ± 5.8% P = 0.001Responder 6.3 ± 0.9% 3.6 ± 0.5% (5 year)Non-Responder 51.1 ± 23.2% P = 0.009 42.8 ± 18.1% P = 0.036; (3-5 year)________________________________________________________________________________Amolik JH et al. Athritis rheum 2007; 56:3044Myasthenia gravis (Lebrun et al. 2016), NMO (Kim et al. 2015), Lupus (Vital et al. 2011), Arthritis (Trouvin et al. 2015)

Audia S et al. Blood. 2011; 118:4394

Childhood(1-13year)

Perc

enta

ge o

f M

em

ory

B c

ells

+ S

D

0

10

20

30

40

50

60Healthy

multiple sclerosis

Adolescent(14-17year)

Adult(25-55 year)

AdultOnset

Paediatric Onset

Memory B cells appear in paediatric MS more rapidly than during aging

Schwartz A et al. 2017. Neurol Neuroimmunol Neuroinflamm 4:e309

MEMORY B CELLS IN MS-PATHOLOGY

________________________________________CD19+, CD27+ Memory B cells

Blood CSF MS Type Remission Relapse Remission________________________________________Paediatric MS 30.1% 20.9% 66.4%

Adult MS 32.2% 26.7% 75.9%________________________________________

MEMORY B CELLS IN MS-PATHOLOGY

Schwartz A et al. 2017. Neurol Neuroimmunol Neuroinflamm 4:e309

Memory B cells drop in Blood during relapse and accumulate in CNS

T CELLS OUTNUMBER MEMORY B CELLS

MYELIN = BROWN

DEMYELINATION

PERIVASCULAR

LESION

RELAPSING MS

BIOLOGY OF MULTIPLE SCLEROSIS

DISPRUPTIVE INFLUENCE

ANMS LESION

T CELLS = 7-24% OF LEUCOCYTES MEMORY B CELLS = 0.2-1.7% OF LEUCOCYTES

Genetic Association with B Cell Activating Factor (BAFF) in Sardinian MSCD24+, CD27+ = Unswitched and Class-Switched memory B cells are increased

Northern European MS may use a different Genetic Pathway

MEMORY B CELLS IN MS-AETIOLOGY

HLA-DRB1*1501: Expressed by B cellsIL2RA (CD25) Expressed by memory B IL7RA (CD127) Expressed by pre-B cells

Many MS Susceptibility Genes withpresumed T cell function are present in oracts of B cell lineagesHLA-DRB1*1501: Expressed by B cellsIL2RA (CD25) Expressed by memory B IL7RA (CD127) Expressed by pre-B cellsTNFRSF1A Expressed by pre B cellsSTAT4 Expressed by pre B cellsIL12A Expressed by Immature B cellsBCL10 Expressed by Immature B cellsCXCR5 Expressed by Memory B cells

HSCT

MEMORY B CELLS IN MS-AETIOLOGY

Antibody Secretion

Cytokine Secretion

APCFunction

B cell

CD22M

HC

Y

EBV

Burns DM et al.Blood. 2015;126:

Memory

MEMORY B CELLS HAVE KILLING POTENTIALTHEY MAY BE T CELL CO-STIMULATION INDEPENDENT

EBV Drives Memory B Cell FormationEBV PROMOTES HUMAN IMMUNITY

van den Heuvel D et al.

J Leukoc Biol. 2017; 101:

949-956

Evolutionary Advantage• Life-long B cell Immunity to help prevent infections

EBV drives proliferation & differentiation of memory B cells and blocks plasma cell differentiation.

Latent EBV virus reservoir in circulating memory B cells

Viral reactivation & shedding in saliva for transmissionImmune mechanisms can limit viral activity

Evolutionary Price

• B cell Lymphomas (Burkitts & Hodgkins) Lymphoma• Glandular Fever (B cell proliferation & CD8 T cell killing)• Autoimmunity (Historically post-reproductive age)

MEMORY B CELLS IN MS-BIOLOGY

CONCLUSIONS

B Cells appear to be the Major Target for Activity in MS

• Limited evidence that T cells control MS (Trial failures).

(CD4 depletion, Th1, Th17 cytokine therapy)

• Efficacy across with a range of different agents via a common B cell mechanism

Treatment Hierachy based on Memory B Cell Depletion Potential

• Memory B cell depletion is a major, common, mediator for relapse control in MS

• Memory B cell function, cytokine activity and EBV activity are interlinked

• There is pathogenic autoantibody in MS (May be secondary to damage)

Unifying mechanism consistent with (a) Aetiology (b) Pathology (c) Therapy

VAGAL NERVE STIMULATION?

MONOCLONAL ANTIBODIES

SMALL MOLECULE INJECTABLES

REMOVAL OF SURVIVAL FACTORS

MOLECULESVIA THE MOUTH

GUILTY-VERDICT

GIVE THE MEMORY B CELL

THE “DEATH PENALTY”

SUMATION

B IS FOR BIOLOGY = RESPONSE TO THERAPY

Unifying mechanism incorporating: (a) Aetiology (b) Pathology (c) Therapy

• Rodents have complicated B cell biology/ do not get infected with EBV

Experimental Autoimmune Encephalomyelitis is Not MS

• Treatment Hierachy based on: Memory B Cell Depletion Potential

Memory T cell Depletion Potential

• Response to Therapy. Fingolimod enhances CCR7-, CD45RO+ cells

(This would contain the pathogenic population…. if MS was T cell-mediated)

Song ZY et al. PoS One. 2015;10(4):e0124923.

CD45RO’sIncrease

CD45RO’s increase in the CNS of MS

• Prevention of Rebound after Natalizumab withdrawal = CD20 B cell depletion

WEINDL ARGUMENTS

NO COMPELLING EVIDENCE PRESENTEDTO CAST DOUBT ON THE CENTRAL ROLE OFMEMORY B CELLS IN MULTIPLE SCLEROSIS

THERE IS REASONABLE DOUBTAGAINTS IT BEING THE T CELL

(Response to therapy)

JUST BECAUSE A CELL IS PRESENT DOES NOT MEAN IT IS IMPORTANT (GUILTY)

MOST IMMUNE CELLS IN LESIONS ARE IRRELEVANT THEY ACCUMULATE BECAUSE OF INFLAMMATORY SIGNALS

The Chewbacca defence: the aim to deliberately confuse the jury rather

than to factually refute the case of the other side.

The concept of disguising a flaw in one's argument by presenting large amounts of irrelevant information

T Cells Control MS….It does not make Sense! Vote for the B’s…B cells = Biology of MS

THANKS FOR LISTENING WITH AN OPEN MIND

Do not acquit the B cell

The Memory B cell is GuiltyGive the T cell a suspended sentence for facilitation

GIVE THE MEMORY B CELL

THE “DEATH PENALTY”

Injectable Oral Antibody

magic bullet

The Chewbacca defence: the aim to deliberately confuse the jury rather

than to factually refute the case of the other side.

The concept of disguising a flaw in one's argument by presenting large amounts of irrelevant information

T Cells Control MS….It does not make Sense! Vote for the B’s…B cells = Biology of MS