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123-P: ILT3-Fc Induces Allospecific CD8+ T Supressor Cells Which Mediate T Cell Anergy and Immunological Tolerance
Abstracts
S95
123-P
ILT3-Fc INDUCES ALLOSPECIFIC CD8⫹ T SUPRESSOR CELLS WHICH MEDIATE T CELL ANERGY AND IMMUNOLOGICAL TOLERANCE. George Vlad, Chris Chang, Zhuoru Liu, Raffaello Cortesini, Nicole Suciu-Foca. Pathology, Columbia University, New York, NY, USA. Aim: The aim of our study was to characterize the molecular changes which determine the conversion of cytolytic CD8⫹ T cells into antigen specific CD8⫹ T supressor cells (Ts). The long term goal of our investigation is to prevent the onset of allograft rejection and progression of autoimmune phenomena. Methods: Allospecific Ts were generated both in vitro and in vivo by exposure of primed T cells to recombinant ILT3-Fc molecule. ILT3-Fc-induced CD8⫹ T cells were tested for suppressor activity and cytokine production. Gene expression arrays were performed to identify changes which occur in ILT3-Fc induced CD8⫹ Ts differentiating them from CTL. The in vivo effect of ILT3Fc was tested in hu-NOD/SCID mice tranplanted with human pancreatic islets. ILT3-Fc was administered before or after the onset of rejection. Results: ILT3-Fc induced Ts displayed significant upregulation of zinc finger transcritional repressors, and cell cycle regulators, while downregulating IL-2, IFN-g, IL-5, IL-10, granzyme B, and HLA class II mRNA. In vitro studies demonstrated that ILT3-Fc induced Ts inhibited CTL function of allospecific T cells as well as the production of Th1, Th2 and Th17 cytokines in primary and secondary MLC. Ts are HLA class I allorestricted inducing the upregulation of inhibitory molecules and downregulation of costimulatory molecules in priming APC, but not in HLA-mismatched controls. ILT3-Fc treatment of hu-NOD/SCID mice transplanted with human islets, resulted in reversal of rejecton and induction of tolerance when administered within 2 weeks of humanization, and was mediated by CD8⫹ Ts. Conclusions: The efficiency of ILT3-Fc as an immunomodulatory agent which reverses allograft rejection and induces transplant tolerance suggests the possibility of using this agent for treatment of autoimmune diseases and transplant rejection.
124-P
EXTENDED HLA HAPLOTYPES CONTAINING INFREQUENT DRB1 ALLELES. Georgena L. Wohlwend,1 Lois E. Regen,1 Maggie S. Sprague,1 Anajane G. Smith,1 Shalini E. Pereira.1,2,3 1Clinical Immunogenetics Laboratory, Seattle Cancer Care Alliance, Seattle, WA, USA; 2FHCRC, Seattle, WA, USA; 3 Lab Medicine, U of Washington, Seattle, WA, USA. Aim: Our laboratory has identified several unusual DRB1 alleles in patients and potential donors typed prior to hematopoietic stem cell transplantation (HSCT) since 2003: DRB1*11:13,*11:29,*13:10,*13:12,*14: 20,*14:21, and *14:48. We decided to type family members to look for extended haplotypes in order to compare our data with published linkage studies. Methods: Archived samples of genomic DNA from patients and informative family members were sequenced using ABI-Big Dye® Terminator chemistry on a 3130XL capillary electrophoresis machine. Results were analyzed using Assign 3.5⫹ / Conexio software and linkages were inferred for five loci: HLA-A, B, C, DRB1 and DQB1. Results: We characterized seven complete haplotypes (one for each allele) in seven independent families. (1) A*11:FXYE, C*12:03, B*18:RRG, DRB1*11:13, DQB1*05:03 (2) A*03:02, C*03:BPSK, B*40:01, DRB1*11:29, DQB1*03:01 (3) A*24:02, C*05:01, B*44:HTH, DRB1*13:10, DQB1*06:HPH (4) A*11:01, C*08:AEK, B*15:02, DRB1*13:12, DQB1*03:02 (5) A*03:01, C*16:02, B*51:08, DRB1*14:20,DQB1*03:01 (6) A*01:01, C*05:01, B*44:HTH, DRB1*14:21, DQB1*06:03 (7) A*24:02, C*01:02, B*15:30, DRB1*14:48, DQB1*03:01 Haplotype #4 appeared in a family self-described as Chinese and haplotype #7 appeared in a family self-described as Hispanic. The other five families described themselves as Caucasian. Conclusions: Knowledge of these rare haplotypes and alleles in different populations and ethnic groups may facilitate unrelated donor searches for patients lacking a family donor.
S95
123-P
ILT3-Fc INDUCES ALLOSPECIFIC CD8⫹ T SUPRESSOR CELLS WHICH MEDIATE T CELL ANERGY AND IMMUNOLOGICAL TOLERANCE. George Vlad, Chris Chang, Zhuoru Liu, Raffaello Cortesini, Nicole Suciu-Foca. Pathology, Columbia University, New York, NY, USA. Aim: The aim of our study was to characterize the molecular changes which determine the conversion of cytolytic CD8⫹ T cells into antigen specific CD8⫹ T supressor cells (Ts). The long term goal of our investigation is to prevent the onset of allograft rejection and progression of autoimmune phenomena. Methods: Allospecific Ts were generated both in vitro and in vivo by exposure of primed T cells to recombinant ILT3-Fc molecule. ILT3-Fc-induced CD8⫹ T cells were tested for suppressor activity and cytokine production. Gene expression arrays were performed to identify changes which occur in ILT3-Fc induced CD8⫹ Ts differentiating them from CTL. The in vivo effect of ILT3Fc was tested in hu-NOD/SCID mice tranplanted with human pancreatic islets. ILT3-Fc was administered before or after the onset of rejection. Results: ILT3-Fc induced Ts displayed significant upregulation of zinc finger transcritional repressors, and cell cycle regulators, while downregulating IL-2, IFN-g, IL-5, IL-10, granzyme B, and HLA class II mRNA. In vitro studies demonstrated that ILT3-Fc induced Ts inhibited CTL function of allospecific T cells as well as the production of Th1, Th2 and Th17 cytokines in primary and secondary MLC. Ts are HLA class I allorestricted inducing the upregulation of inhibitory molecules and downregulation of costimulatory molecules in priming APC, but not in HLA-mismatched controls. ILT3-Fc treatment of hu-NOD/SCID mice transplanted with human islets, resulted in reversal of rejecton and induction of tolerance when administered within 2 weeks of humanization, and was mediated by CD8⫹ Ts. Conclusions: The efficiency of ILT3-Fc as an immunomodulatory agent which reverses allograft rejection and induces transplant tolerance suggests the possibility of using this agent for treatment of autoimmune diseases and transplant rejection.
124-P
EXTENDED HLA HAPLOTYPES CONTAINING INFREQUENT DRB1 ALLELES. Georgena L. Wohlwend,1 Lois E. Regen,1 Maggie S. Sprague,1 Anajane G. Smith,1 Shalini E. Pereira.1,2,3 1Clinical Immunogenetics Laboratory, Seattle Cancer Care Alliance, Seattle, WA, USA; 2FHCRC, Seattle, WA, USA; 3 Lab Medicine, U of Washington, Seattle, WA, USA. Aim: Our laboratory has identified several unusual DRB1 alleles in patients and potential donors typed prior to hematopoietic stem cell transplantation (HSCT) since 2003: DRB1*11:13,*11:29,*13:10,*13:12,*14: 20,*14:21, and *14:48. We decided to type family members to look for extended haplotypes in order to compare our data with published linkage studies. Methods: Archived samples of genomic DNA from patients and informative family members were sequenced using ABI-Big Dye® Terminator chemistry on a 3130XL capillary electrophoresis machine. Results were analyzed using Assign 3.5⫹ / Conexio software and linkages were inferred for five loci: HLA-A, B, C, DRB1 and DQB1. Results: We characterized seven complete haplotypes (one for each allele) in seven independent families. (1) A*11:FXYE, C*12:03, B*18:RRG, DRB1*11:13, DQB1*05:03 (2) A*03:02, C*03:BPSK, B*40:01, DRB1*11:29, DQB1*03:01 (3) A*24:02, C*05:01, B*44:HTH, DRB1*13:10, DQB1*06:HPH (4) A*11:01, C*08:AEK, B*15:02, DRB1*13:12, DQB1*03:02 (5) A*03:01, C*16:02, B*51:08, DRB1*14:20,DQB1*03:01 (6) A*01:01, C*05:01, B*44:HTH, DRB1*14:21, DQB1*06:03 (7) A*24:02, C*01:02, B*15:30, DRB1*14:48, DQB1*03:01 Haplotype #4 appeared in a family self-described as Chinese and haplotype #7 appeared in a family self-described as Hispanic. The other five families described themselves as Caucasian. Conclusions: Knowledge of these rare haplotypes and alleles in different populations and ethnic groups may facilitate unrelated donor searches for patients lacking a family donor.