4.8
#24-OR
POST-TRANSPLANT DETECTION OF DONOR-REACTIVE ALLOANTIBODIES BY TMS (ELISA) CORRELATES WITH ADVERSE CLINICAL OUTCOME.
Patrick W. Adams, MS,CHS , Ronald P. Pelletier, MD , Jenny F. Gullett and Charles G. Orosz, PhD . Columbus OH, OSUMC, 43210, Surgery .

---

We have recently employed an ELISA-based assay (TMS, GTI Inc.) to measure patient IgG binding to HLA Class I or Class II molecules derived from donor leukocytes. We used this assay to evaluate the incidence, MHC Class specificity, and clinical significance of anti-donor antibodies detected after transplantation in kidney and kidney-pancreas recipients. We have tested 357 recipients (mean follow-up 3.6+/-2.1 years). Overall incidence of antibodies was 30%, with 12% exhibiting Class I anti-donor antibodies, 8% exhibiting Class II anti-donor alloantibodies, and 10% having antibodies to both Class I and Class II. There was a strong correlation between the presence of anti-donor Class I antibodies and acute rejection (p<0.001), chronic rejection (p=0.006), and graft loss (p=0.02). HLA Class II donor-reactive antibodies correlated very strongly with acute rejection (p=0.001) and chronic rejection (p<0.001). We conclude that the post-transplant development of anti-donor HLA Class I or II alloantibodies is a serious risk factor for poor graft outcome, and that the ELISA TMS assay is an excellent method for detecting clinically relevant donor-reactive HLA antibodies during the post-transplant period.