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Molecules and mechanisms of the graft versus leukemia (GVL) effect

Molecules and mechanisms of the graft versus leukemia (GVL

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Page 1: Molecules and mechanisms of the graft versus leukemia (GVL

Molecules and mechanisms of the graft versus leukemia (GVL) effect

Page 2: Molecules and mechanisms of the graft versus leukemia (GVL

• University of Manitoba Faculty of Medicine Archives

Page 3: Molecules and mechanisms of the graft versus leukemia (GVL

The “Goldenberg” Rules

• We are fortunate to have the opportunity to participatein research. Do not squander the opportunity --commit yourself to a life-time of learning

3. Treasure the time you have for research, it is special

2. Patients and professors can teach us much, if we payattention

4. Use correct grammar!!

Page 4: Molecules and mechanisms of the graft versus leukemia (GVL

Immunologic Non Identity Contributes To The Efficacy Of Allogeneic HCT

Horowitz, Blood 1990

Twins

HLA id sibs

+ GVHD

CML > CLL, low grade lymphoma, myeloma > AML, ALL

Page 5: Molecules and mechanisms of the graft versus leukemia (GVL

• Full donor chimerism• No circulating malignant cells

Myeoloablative Conditioning (Age <50)

Success rate ~ 30 - 60% in AML/ALL/MDS, 80% CML

• Toxicity• GVHD• Relapse

• Mixed hematopoietic chimerism• Circulating malignant cells• CSA/MMF immunosuppression

Nonmyeloablative Conditioning (Age up to 70)

Success rate ? (~50% for indolent leukemias (CLL), follicular lymphoma

• GVHD• Relapse

Page 6: Molecules and mechanisms of the graft versus leukemia (GVL

Tolerance

Donor T Cells

Donor Cells

Genetic Polymorphism Results in the Display of Unique Peptides by Cell Surface MHC Molecules

• nonsynonymous SNPs• 5’ “untranslated regions”• differential gene expression• peptide splicing/reassortment

Recipient Cells

Activation

Page 7: Molecules and mechanisms of the graft versus leukemia (GVL

• Antigens are “foreign” to donor T cells• T cell responses are of high avidity• T cell responses may be multivalent

• Responses typically involve both CD8 and CD4 T cells

Minor H Antigens - Characteristics of EffectiveTargets for Cancer Immunotherapy

Can the GVL effect for acute leukemias be augmented and separated from GVHD?

Page 8: Molecules and mechanisms of the graft versus leukemia (GVL

Tissue Expression of Minor H Antigens May Provide ABasis for Segregating GVHD and GVL Responses

Page 9: Molecules and mechanisms of the graft versus leukemia (GVL

Isolation of T Cells Specific For Recipient Minor H AntigensAfter In Vivo Priming

γ-irradiated APC (PBMC or leukemia)from the recipient pre transplant

Assay for cytolytic activityClone reactive T cell lines and characterize T cell clonesfor phenotype, HLA restricting allele, tissue expression

PBMC from recipientpost transplant

T Cell Clone

B-LCL

PHA-Blasts

Fibroblasts

Target Cells

% L

ysis

0

10

20

30

40

50

60

70

80

SKH-13 DJG-24

Donor Recipient Donor Recipient

Page 10: Molecules and mechanisms of the graft versus leukemia (GVL

ClonogenicLeukemic Progenitors

Leukemic Stem Cell

SelfRenewal

CD34+CD38-

375 cGYAML +/- CTL

25

50

Control MHAg CTL

% Engraftment

Engraftment

• Bonnet D. et al. Proc Natl Acad Sci 1999

Part 1. Lost in Translation

“Hematopoietic Lineage”-Restricted Minor H Antigen

Page 11: Molecules and mechanisms of the graft versus leukemia (GVL

Adoptive Transfer of Minor H Antigen-Specific T Cell Clones To TreatPost Transplant Leukemic Relapse

Outcome - Post transplant Relapse• Enroll patients with advancedleukemia (>2nd CR, refractorydisease)

• Isolate CD8+ T cell clones fromrecipients early post transplant

• Select clones that lyse recipienthematopoietic cells (includingleukemia) BUT NOT skin fibroblasts

• QC testing & cryopreservation

• Treat patients at relapse withescalating doses of T cells

• Evaluate toxicity, T cell migrationand persistence, and antitumoractivity

Page 12: Molecules and mechanisms of the graft versus leukemia (GVL

CTX *

-2 1 4 11 21 28 ≥35

CTL Infusions IL-2CTL Infusions

Day

3.3x107 3.3x108 3.3x109 3.3x109 3.3x109 3.3x109

• Early TRM or relapse -- 32% of enrolled patients • 7 patients relapsed and received T cell infusions• 3 patients relapsed and had T cells available - not treated • 6 patients have T cells available and remain at risk

Page 13: Molecules and mechanisms of the graft versus leukemia (GVL

UPN-15652 - primary refractory Ph+ ALL

- MRD SCT with Cy/TBI

- Isolated minor H antigen-specific CTL clones

- Relapse 7 months post SCT (>90% blasts)

- Cytoreduction with Mitoxantrone/VP16

0 10 20 30 40 50 60 70

Recipient LCL

RecipientFibroblasts

LeukemicBlasts

Donor LCL

DonorFibroblasts

% Specific Lysis

CTL Clone 11C6

Page 14: Molecules and mechanisms of the graft versus leukemia (GVL

T Cells

x 103

0

5

10

15

20

25

30

35

-11 -5 1 7 13 19 25 31 37 43 49 57

WBC

Blasts

Day

*Skin GVHD(PCR -ve for CTL)

Toxicity: * Lung Toxicity

Blasts in BM 90% >15%

Page 15: Molecules and mechanisms of the graft versus leukemia (GVL

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Transferred CTL Localize At Site of Tissue Injuryand Modulate TcR Expression

Pre-Inf

4 hr PostT Cells

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MP

2 days PostT Cells

Modulation of Vβ 13 TcR Expression in bronchoalveolar lavage fluid

Detection of CTL by clone-specific PCR

Page 16: Molecules and mechanisms of the graft versus leukemia (GVL

Blasts in BM 90% >15% <5%

x 103

0

5

10

15

20

25

30

35

-11 -5 1 7 13 19 25 31 37 43 49 57

WBC

Blasts

Day

T Cells

*Skin GVHD(PCR -ve for CTL)

Toxicity:

Methylprednisolone

* Lung Toxicity

Page 17: Molecules and mechanisms of the graft versus leukemia (GVL

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Post T cell infusions - Remission

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Post chemotherapy - Relapse

UPN15652

Page 18: Molecules and mechanisms of the graft versus leukemia (GVL

No GVHD,toxicity

<5% CR80%90%#3 ALL

OutcomePost T CellsPost CTXPrePatient

Bone Marrow BlastsUPN 19492

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+ – PBL M PBL M PBL M

3 4 6Infusion #

Clone-specificTcR V beta PCR

Page 19: Molecules and mechanisms of the graft versus leukemia (GVL

Results

• Toxicity

• 3/7 patients (2 lung, 1 GVHD)

• Transfer efficiency and migration

• high levels of transferred T cells in the blood and bonemarrow (>8% of PBMC), t1/2 of transferred cells in theblood ~ 7 days

• *Efficacy

• 4/6 evaluable patients achieved CR, including 2 withpersistent disease after chemotherapy.

• 6/7 patients subsequently progressed 4 -15 monthsafter therapy, 1 patient remains alive >39 months

Page 20: Molecules and mechanisms of the graft versus leukemia (GVL

• Isolation of minor H antigen specific T cells from patients transplanted for advanced leukemia is feasible but problematic

• Separation of GVL effect from toxicity cannot be achieved by selecting clones based on in vitro cytotoxicity against non-hematopoietic targets

3. Adoptively transferred CD8+ T cell clones exhibit limited persistence in vivo

Mechanisms responsible may include:• high antigen load - activation induced cell death• inadequate T helper responses/prosurvival cytokines• intrinsic defect due to culture and/or differentiation• other

Page 21: Molecules and mechanisms of the graft versus leukemia (GVL

Part 2. Back to Basics

Page 22: Molecules and mechanisms of the graft versus leukemia (GVL

cDNA Library

pEAK10 Plasmid Vector

Plasmid VectorEncoding HLA-Allele

COS Cells

+

IFN γ(ELISA)

CTL Clone

Identification of the Genes that Encode Minor H Antigens

Recipient EBV-LCL

mRNA For mHAg

cDNA

Page 23: Molecules and mechanisms of the graft versus leukemia (GVL

UDP Glycosyltransferase 2 Family, Polypeptide B17 (UGT2B17)Encodes a Minor H Antigen Presented by HLA A29

Construct I (52-513)

Construct II (493-993)Construct III (493-564)

ATGTAA

TAA

ATG TAA

ATG (−)(+)(+)

UGT2B17 cDNA 1 52 1644 21072H9

1 383 2335 2958cDNA

Peptide concentration (nM)

Spe

cific

lysi

s (%

)

5060

40302010

00 10-5 10-4 10-3 10-2 10-1 100 101 103102 104

Recognition of Donor LCLPrecultured with Synthetic Peptide HLA-A29 Anchors

1 2 3 4 5 6 7 8 9 E Y

V L L A D A V N P C G E L L A E L L N I P F L Y

CTL Clone PL-8

Page 24: Molecules and mechanisms of the graft versus leukemia (GVL

UGT2B17

GAPDH

Unrelated HLA-A29+ LCLRecipient LCL

DonorLCL Ag+ Ag+ Ag- Ag-

Northern Blot Analysis of Total RNA

Immunogenicity of UGT2B17 Results from Differential Transcription in Recipient versus Donor Cells

Page 25: Molecules and mechanisms of the graft versus leukemia (GVL

SSP-PCR Primers exon 1 (b)

SSP-PCR Primers exon 1 (a)

PCR Primers for5’ upstream

UGT2B17 gene 1 2 3 4 5 6Exon

- 370 - 30

4431

400 751

1394 1594SSP-PCR Primers for exon 6

52 16441365775535 5641 2107

ATG TAGEpitope5' 3'

Probe for Northern

Unrelated HLA-A29+ LCLRecipient LCL

DonorLCL Ag + Ag + Ag − Ag −

exon 1 (a)

5’ upstream

GAPDH

exon 1 (b)

exon 6UGT2B17

• 11% ofCaucasiandonors aredeficient inUGT2B17

Page 26: Molecules and mechanisms of the graft versus leukemia (GVL

Tissue Expression MattersSSP-PCR for UGT2B17 cDNA from Human Tissues

UGT2B17

GAPDH

Hea

rt

Bra

inP

lace

nta

Lung

Live

r Ske

leta

l mus

cle

Kid

ney

Pan

crea

sS

plee

n

Thym

usP

rost

ate

Test

isO

vary

Sm

all i

ntes

tine

Col

on

• the recipient had acute GI/liver GVHD and cGVHD involving the GI tract

Page 27: Molecules and mechanisms of the graft versus leukemia (GVL

241 336

MPHSPLGSMPEIRDNSPEPNDPEEPQEVSSTPSDKKGKKRKRGIWSTPKRRHKKKSLPRGTASSRHGIQKKLKRVDQVPQKKDDSTCNSTVETRAQ MSTPKRRHKKKSLPRGTASSRHGIQKKLKRVDQVPQKKDDSTCNSTVETRAQ

MPHSPLGSMPEIRDNSPEPNDPEEPQEVSSTPSDKKGKKRKRGIWSTPKRRHKKKSLPRGTASSR

STPKRRHKKKSLPRGTASSR

+++

DRN-7 CTL Recognize A Minor H Antigen Presented By HLA -A3And Encoded by the SP110 gene

-20

A/G G/G A/G G/G G/G A/G A/A G/G A/G A/G G/G

020406080

100

DRN CAN SEB ABB WGB RLB MDK TM WAS JDS JR

% S

peci

fic L

ysis

PCR

-RFL

P

Genotype

CTL Clone DRN-7

Donor SP110 - G

Page 28: Molecules and mechanisms of the graft versus leukemia (GVL

0 500 1000 1500 2000 2500

STPKRRHKKKSLPRGTASSR

IFN-gamma (pg/ml)

Non-Electroporated

Electroporated

>2000

(SP110286-305)

What is the SP110 epitope?

• 20 mer peptide containing G-->R substitution sensitized donor LCL for recognition by CTL but only at high concentrations (>10 μg/ml)

• No synthetic 8 - 12 mer peptide comprised within the 20 mer sequence could be identified that sensitized target cells for recognition by the CTL clone

• Consistent with a requirement for a posttranslational modification for epitope generation

Page 29: Molecules and mechanisms of the graft versus leukemia (GVL
Page 30: Molecules and mechanisms of the graft versus leukemia (GVL

Does the Proteasome Generate The SP110 Epitope?

Page 31: Molecules and mechanisms of the graft versus leukemia (GVL

STPKRRHKKKSLPRGTASSR

But ---- STPKSLPRGT did not senstitize target cells for recognition

0 1 2 3 4 5 6 7 8

Interferon gamma (ng/ml)

STPK + SLPRGTASSR

STPK + SLPRGTASSR

Is the SP110 epitope a product of peptide splicing?

Electroporated

PulsedSLPRGTASSRSTPK

E or P

Page 32: Molecules and mechanisms of the graft versus leukemia (GVL

HLA A3 binding motif

_ L _ _ _ _ _ _ K

STPK SLPRGT SLPRGTSTPK

STPKRRHKKKSLPRGTASSR

Page 33: Molecules and mechanisms of the graft versus leukemia (GVL

-10

0

10

20

30

40

50

60

70

80

90

0.01 0.1 1 10 100 1000

[Peptide] nM

% S

peci

fic L

ysis

SLPGGTSTPK

SLPRGTSTPK

STPKSLPRGT

Peptide Splicing With A Twist -- Rearrangement of SP110Encoded Peptides Creates The DRN-7 Epitope

Page 34: Molecules and mechanisms of the graft versus leukemia (GVL

The Putative DRN-7 Epitope SLPRGTSTPK Co-elutes WithThe Naturally Processed Epitope

Page 35: Molecules and mechanisms of the graft versus leukemia (GVL

01020304050607080

Donor LCL

Recip-LCL

RecipT Cells

RecipFibroblasts

HLA-A3+LCL

HLA-A3+ CLL

Target Cell

% Lysis

CloneKSN-7A7

1.5 Kb

PANE-1 transcript k

-10

0

10

20

30

40

50

60

70

80

90

100

110

1.E-03 1.E-02 1.E-01 1.E+00 1.E+01 1.E+02 1.E+03

[Peptide], nM

% S

peci

fic L

ysis

RVWDLPGVLK on GAO LCLRVWDLPGVLK on T2-A3SLPRGTSTPK on GAO LCLSLPRGTSTPK on T2-A3

PANE-1 transcript k -- a B-lineage minor H antigen

Page 36: Molecules and mechanisms of the graft versus leukemia (GVL

8.4 Kb

PANE1transcript c

PANE1transcript k

1.5 Kb

PANE1transcript c

PANE1transcript k

A

M G R V W D L P GaggcaggccacggagatacctcgtggaaggaggaacagcaagtgcATGGGCCGAGTGTGGGACTTGCCTGGT V L K TGTGCTCAAGgtctggcaggcaggcctgggtggctgcagcacaatagcaaagggcgggttggggtggagaaatcaggaatggtggggctggatcagtggagcctggtggggagctgctggagggcttggggccagggagggatgtggcctgacttgggttttaaatggacccctctggctgccgggaggagagtggactgaagggaaactagggcagaaatagagagacaggtctggaggctctttctttctttctttctttctttctttttctttctttctttctttctttctttctttctttctttttctttctttctttctttctttttctttctttttctttctttttctttctttttctttcttttttgagacagacactgggcagcatcgtgttcttccagcggacgtgtctagaacatctgtgcccgggcctagagcagtcttgtccctctctggccccacagctcccctgggcccattcctttttgatggcaccttcttatctgtggtgagggccacccgctgcccctccctccttcctatccctgtatcttctgctccctggtcttgagcatctggggcccgagctgcctgggcattggttggaagtagccctgattcagagctcagctctggagtcactagctgggtgaccctagacagtttgttcgacctagccagccttgttaagccttcatttcctcttgagcaggaggtcaggctctggatgtctccggaggttgtttgaaggattgggcaagctgaggcagttggaagctactctgaggtgtggcatgaatgagggcgtggctgtggtgggcagtggtgacctgagctacccccaagtatccgcccccagccctgctctggcagcccctgcagctgctctgggtaagggagcagggccagcattctatctcactgctgttct V E G F R A T M A Q R L V R V L Q I CctgctctccccgcaggtGGAAGGCTTTAGGGCCACCATGGCGCAGCGCCTGGTGCGCGTGCTGCAGATCTGT A G H V P G V S A L N L L S L L R S S E G P S LGCTGGCCACGTGCCCGGTGTCTCAGCTCTGAACCTGCTGTCCCTGCTGAGAAGCTCTGAGGGCCCCTCCCTG E D L *GAGGACCTGTGAGGGTGGCTGGCCCCTGGGCTGCCCCTTCTCATGGCTTCGTGCTGACTCCATAAACATTCTCTGTTGAGGATGTCCAGTCAGGGCTTGACAGGCCCAGGCTCAGCCCGCCGTGGCTGGGAAGGTTCCCTGCAGTGCCAGTGCTGCAGCAGGGAGAGCTGGGCAGAAGCAGCGAGGGGGCCCAGCTGGCGAGACTGTAGCCCCCTCCCACTCCCACACTCACTCTTGCAGAGCCTGTGTCTTTAAGCAGCTGGCGTGTTACATCTCCATTTAAGGTTTCCTTTGAACAAAAGGTCTGTGGCTAAAAAAAGTTTAAAAATCaaaaaaaaaaaaaaaaaaaaaaaaa

Page 37: Molecules and mechanisms of the graft versus leukemia (GVL

Bra

inH

eart

Lung

Live

rK

idne

ySk

elet

al M

us.

Pros

tate

Test

isO

vary

Panc

reas

Stom

ach

Smal

l Int

estin

eC

olon

Res

t. C

D19

+

Act

. CD

19+

EB

V-L

CL

PANE-1 is selectively expressed in B-lineage cells

Page 38: Molecules and mechanisms of the graft versus leukemia (GVL

Expression of PANE-1 by q-PCR

0 20 40 60 80 100 120

Brain

Heart

Lung

Liver

Kidney

Pancreas

Small Intestine

Colon

Prostate

Testis

Ovary

Skeletal Muscle

Spleen

Thymus

Resting CD19

Activated CD19

CLL -1

CLL -2

CLL -3

CLL -4

CLL -5

CLL -6

CLL -8

CLL -9

Tis

sue S

ou

rce

Relative Level of Expression

Transcript cTranscript k

118124330776361126344978

221

Page 39: Molecules and mechanisms of the graft versus leukemia (GVL

Minor Hantigen

HLArestriction

Gene/chromosome Peptide sequence Tissue distribu tion Identi fication technique 1

HA-125 HLA A201 KIAA0223/19 p13 VLHDDLLEA Hematopoieti c HPLC with mass spectometry

HA-126 HLA B60 KIAA0223/19 p13Chromosome

KECVLHDDL Hematopoieti c Polymorphi c peptide s creening

HA-227,28 HLA A201 MYOG1/7 YIGEVLSV Hematopoieti c HPLC with mass spectometry

HA-329 HLA A1 Lbc oncogene/15q24-25 VTEPGTAQY Ubiquitou s HPLC with mass spectometry

HA-830 HLA A201 KIAA0020/9 RTLDKVLEV Ubiquitou s HPLC with mass spectometry

HB-131,32 HLA B44 Chromosome 5q32 EEKRGSLHVW Hematopoieti cesp B cell leukemias

cDNA expression cloning

UGT2B17 33 HLA 2902HLA B4403

UGT2B17 /4q13 AELLNIPFLY Ubiquitou s cDNA expression cloning

BCL2A134 HLA A24 BCL2A1/15q2 4.3 DYLQYVKQI Hematopoieti c Genetic linka ge analysis

BCL2A134 HLA B4403 BCL2A1/15q2 4.3 KEFEDDIINW Hematopoieti c Genetic linka ge analysis

HY B7 (SMCY)35 HLA B702 SMCY SPSVDKARAEL Ubiquitou s HPLC with mass spectometry

HY A2 (SMCY)36 HLA A201 SMCY FIDSYICQV Ubiquitou s HPLC with mass spectometry

HY A1 (DFFRY)37 HLA A101 DFFRY IVDCLTEMY Ubiquitou s HPLC with mass spectometry

HY B60 (UTY)38 HLA B60 UTY RESEESVSL Ubiquitou s cDNA expression cloning

HY B8 (UTY)39

HY A2 (UTY)HLA B8HLA A2HLA A2

UTYUTYUTY

LPHNHTDLYLQQNTHTLLLIADNPQL

Ubiquitou s, Highlevels in AML

cDNA expression cloning

HY DQ5 (DBY)40 HLA DQ5 DBY HIENFSDIDMGE Ubiquitou s cDNA expression cloning

HY DRB341 HLA DRB3 RPS4Y VIKVNDTVQI Not reported cDNA expression cloning

C22orf18 HLA A3 C22orf18 RDWDLPGVLK B-cell (CLL) HPLC/mass spectrometry

SP110 HLA A3 SP110 SLPRGTSTPK** Hematopoieiti c, ifninducible

CDNA expression cloning

LYSE 95-4- F4 HLA A2 LYSE 95-4- F4 SNP (L H) Not determined(Renal cell Ca)

Genetic linka ge analysis

Molecularly Characterized Minor Histocompatibility Antigens

Page 40: Molecules and mechanisms of the graft versus leukemia (GVL

CCR-7 CD28

Ag

TCM

TEM

CCR-7 CD28

CD28

Effector Memory

CD45RO

CCR-7 CD28

CD62L

Naive

CD45RA

Part 3 - A Naïve Answer (?)

• GVHD is common after unmodified allogeneic HCT requiring the administration of immunosuppression, poor platform for immunotherapy to augment GVL effect

Page 41: Molecules and mechanisms of the graft versus leukemia (GVL

Chen B et al. Blood 2004Xystrakis E. et al Eur J Immunol 2004Zhang Y et al J Immunol 2005

Page 42: Molecules and mechanisms of the graft versus leukemia (GVL

9.2%

CMV Fibroblasts

IFN-γ

CD

8

In the absence of priming of the donor to alloantigens, the overwhelming majority of alloreactivity should reside in the naïve T cell pool

CCR-7 CD28

Ag

TCM

TEM

CCR-7 CD28

CD28

Effector

CD45RO

CCR-7 CD28

CD62L

Naive

<1% of TcR diversity pathogen-specific(CMV, EBV, HSV)

>99% of TcRdiversity (Arstila etal. Science, 1999)

CD45RA

Page 43: Molecules and mechanisms of the graft versus leukemia (GVL

Direct Analysis of Minor H Antigen AlloreactivityIn Naïve and Memory Subsets of CD8+ T Cells

• 5 HLA identical sibling pairs

• Purified naïve (Tn -- CD45RA, CD62L+) and memory (Tm -- CD45RO) T cells

• Limiting dilution assay using purified Tn and Tm cells as responder cells, recipient dendritic cells as the APC, and IL12/IL15

• Recipient and donor DC or CD40L B cells astarget cells, validation of positive wells

Page 44: Molecules and mechanisms of the graft versus leukemia (GVL

CD45RO

100 101 102 103 104

72604.169

100 101 102 103 104

100 101 102 103 104

100 101 102 103 104

72604.173

100 101 102 103 104

100 101 102 103 104

72604.175

100 101 102 103 104

100 101 102 103 104

72604.171

100 101 102 103 104 100 101 102 103 104CD45RA APC

72604.174

99

98

41

74

94

CD62

L

CD45RA

CD62

LCD

27

100 101 102 103 104

95

CD28

Naïve T Cell Purification

Page 45: Molecules and mechanisms of the graft versus leukemia (GVL

Frequency of Minor H Antigen Specific CD8 T cellsCD45RA vs CD45 RO

40.00

60.00

80.00

100.00

10000 100000 1000000 10000000Number of CD8 T Cells

Frequency of Minor H Antigen Specific CD8 T cells CD45RA vs CD45 RO - Validation Assay

40.00

60.00

80.00

100.00

10000 100000 1000000 10000000

Number of CD8 T Cells

• T cell clones specific for broadly expressed and lineage restricted minor H antigens

Page 46: Molecules and mechanisms of the graft versus leukemia (GVL

Stem Cells +Memory T cells

Conditioning Decreased posttransplant immunosuppression

Predicted Outcome:• rapid immunologic recovery• few infections• little or no GVHD

How to restore the GVL effect?- improved platform for immunotherapy- vaccinate donors to elicit lineage restricted minor H

antigen specific memory T cellsOR

- T cells specific for leukemia associated or minor Hantigens isolated from naïve donor T cells could be

adoptively transferred

Page 47: Molecules and mechanisms of the graft versus leukemia (GVL

Pilot trial of naïve T cell depletion to reduce GvHD

• HLA id siblings (acute leukemia, donor parity/transfusion hx)

• high stem cell dose

• CD34 selection, CD62L depletion (removes all naive and central memory cells) -- administer defined dose of memory T cells

• FK506/MTX initially, if reduction in GvHD, test FK506 alone (MTX may inhibit homeostatic proliferation of memory T cells and delay immune reconsititution to pathogens)

• End points- engraftment - GVHD- relapse - immune reconstitution - infections (CMV, EBV, HSV, aspergillus)

Page 48: Molecules and mechanisms of the graft versus leukemia (GVL

Donor Recipient

• Genotyping for relevant minor H antigens based on HLA type

• Vaccination of the donor to one or more antigens

• Preparation of stem cell graft (naïve T cell depletion)

• Vaccination of recipient to boost leukemia associated minor H antigen-specific T cell responses

Page 49: Molecules and mechanisms of the graft versus leukemia (GVL

Edus H. WarrenMarc GavinJeff MitoMichele Brown

QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Nathalie VigneronBenoit van den Eynde(Ludwig Institute, Brussels)

Tony BricknerVic Engelhard(University of Virginia)

Warren Shlomchik(Yale University)

MarieBleakleyAudrey MollerupThomas ManleyLarry AndersonTory Yamamoto

Tetsuya Nishida