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Effect of anti-Fab antibodies on human renal allografts
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Abstracts
EFFECT OF ANTI-FAB ANTIBODIES ON HUMAN RENAL ALLOGRAYI'S D Chia, PI Terasaki, N Feduska, and L Sugich, UCLA Tissue TypingLab., Los Angeles, CA Anti-Fab antibodies (antibodies against antibodies) are interesting since they might be favorable to transplants because of their possible role as anfi-idiotypic antibodies. We chose to study antibodies to Fab and antibodies to F(ab)2 (which includes the hinge region). Pretransplant sera from 485 patients were tested for anti-F(ab)2 and from 290 patients for anti-Fab by an ELISA assay. Purity for the Fab and F(ab)2 fragments was confirmed by SDS-PAGE and immunoassay. Interestingly, approximately 80% of normal persons and 79% of patients being transplanted for the first time had anti-Fab antibodies and 79% had anti-F(ab)2 antibodies. Thus the antibody is "naturally" occuring. The figure shows that graft survival was significantly lower in patients with anti-Fab antibodies than those without antibodies. Thus, rather than act as anti-idiotypic antibodies, these antibodies were associated with poor function. Antibodies to F(ab)2 had no effect on graft outcome. The anti-Fab antibodies had an adverse effect of graft outcome in all of 100. )~..~. ~. p
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ALLO- AND A U T O C R O S S M A T C H E S AFTER TRANSPLANTATION. PM van den Ber~Loonen, MJHT Overhof, MCJ Tillemans, *JP van Hooff. Tissue T y p i n g Laboratory and *Department of Nephrology, University Hospital Maastricht, the Netherlands. A n t i b o d y development was investigated in 61 k i d n e y a l l o g r a f t s with a negative X m a t c h at the time of transplantation and a follow-up time of at least 1 year. Presence of T and B-cell allo- and a u t o a n t i b o d i e s was determined by performing Xmatches with frozen donor spleen cells and sera drawn before and after transplantation (NIH,TCF,DTT). After t r a n s p l a n t a t i o n 33 patients did not form alloantibodies (group I), 15 patients showed reactivity to donor B-cells but not Tcells (group 2) and 13 reacted with donor T-cells (group 3). Graft survival in the different groups was 91%, 86% and 62% respectively. No a u t o a n t i b o d i e s were shown in group i, from group 2 six patients showed auto-B-cell reactivity and in group 3 six patients were shown to possess auto-T-cell and 2 auto-B-cell antibodies. Since it has been claimed that graft survival is influenced by the formation of T-cell antibodies we selected the patients with a functioning graft after i year and no rejection crises to see whether this group lacked antibody development. From 31 patients 22 stayed negative, 8 became B-cell positive and 1 showed a T-cell positive donor Xmatch. A u t o a n t i b o d i e s could only be demonstrated in 2 B-cell positive patients. We conclude that the development of a positive T-cell donor Xmatch after t r a n s p l a n t a t i o n influences graft survival, but is not necessarily a prediction of graft failure. About half of the positive donor Xmatches is also auto-Xmatch positive.
#111 8.4
Abstracts
EFFECT OF ANTI-FAB ANTIBODIES ON HUMAN RENAL ALLOGRAYI'S D Chia, PI Terasaki, N Feduska, and L Sugich, UCLA Tissue TypingLab., Los Angeles, CA Anti-Fab antibodies (antibodies against antibodies) are interesting since they might be favorable to transplants because of their possible role as anfi-idiotypic antibodies. We chose to study antibodies to Fab and antibodies to F(ab)2 (which includes the hinge region). Pretransplant sera from 485 patients were tested for anti-F(ab)2 and from 290 patients for anti-Fab by an ELISA assay. Purity for the Fab and F(ab)2 fragments was confirmed by SDS-PAGE and immunoassay. Interestingly, approximately 80% of normal persons and 79% of patients being transplanted for the first time had anti-Fab antibodies and 79% had anti-F(ab)2 antibodies. Thus the antibody is "naturally" occuring. The figure shows that graft survival was significantly lower in patients with anti-Fab antibodies than those without antibodies. Thus, rather than act as anti-idiotypic antibodies, these antibodies were associated with poor function. Antibodies to F(ab)2 had no effect on graft outcome. The anti-Fab antibodies had an adverse effect of graft outcome in all of 100. )~..~. ~. p
#112 8.4
ALLO- AND A U T O C R O S S M A T C H E S AFTER TRANSPLANTATION. PM van den Ber~Loonen, MJHT Overhof, MCJ Tillemans, *JP van Hooff. Tissue T y p i n g Laboratory and *Department of Nephrology, University Hospital Maastricht, the Netherlands. A n t i b o d y development was investigated in 61 k i d n e y a l l o g r a f t s with a negative X m a t c h at the time of transplantation and a follow-up time of at least 1 year. Presence of T and B-cell allo- and a u t o a n t i b o d i e s was determined by performing Xmatches with frozen donor spleen cells and sera drawn before and after transplantation (NIH,TCF,DTT). After t r a n s p l a n t a t i o n 33 patients did not form alloantibodies (group I), 15 patients showed reactivity to donor B-cells but not Tcells (group 2) and 13 reacted with donor T-cells (group 3). Graft survival in the different groups was 91%, 86% and 62% respectively. No a u t o a n t i b o d i e s were shown in group i, from group 2 six patients showed auto-B-cell reactivity and in group 3 six patients were shown to possess auto-T-cell and 2 auto-B-cell antibodies. Since it has been claimed that graft survival is influenced by the formation of T-cell antibodies we selected the patients with a functioning graft after i year and no rejection crises to see whether this group lacked antibody development. From 31 patients 22 stayed negative, 8 became B-cell positive and 1 showed a T-cell positive donor Xmatch. A u t o a n t i b o d i e s could only be demonstrated in 2 B-cell positive patients. We conclude that the development of a positive T-cell donor Xmatch after t r a n s p l a n t a t i o n influences graft survival, but is not necessarily a prediction of graft failure. About half of the positive donor Xmatches is also auto-Xmatch positive.