Anti-HLA Antibodies and Kidney Allograft Outcomes in Recipients with Donor Bone Marrow Cell Infusion

Background: Anti-HLA-antibodies are known to affect the allograft survival in transplant recipient patients. Objective: The aim of this study was to evaluate the association between anti-HLA antibodies and kidney allograft outcomes, particularly in recipients with concur-rent donor bone marrow cell infusion (DBMI). Methods: Between June 2006 and May 2007, forty living unrelated donor kidney transplants consisting of 20 recipients with DBMI and 20 without infusion entered into the study and were monitored prospectively for one year. Pre- and post-transplant (days 14, 30, and 90) sera were screened for the presence of anti-HLA class-I and II antibodies, and subsequently positive sera retested with ELISA spe-cific panel for antibody specification. Results: Of 40 patients, 9 (22.5%) experienced acute rejection episodes (ARE) (6/20 cases in non-infused versus 3/20 in DBMI patients). The prevalence of anti-HLA antibodies before and after transplantation were higher in patients with ARE compared to non-rejecting ones (88.8% vs. 38.7%, p=0.01 and 66.6% vs. 25.8%, p=0.04, respectively). A total of 10% (4/40) of patients developed donor specific anti-HLA antibodies (DSA) and in this regard 2 patients from the control group experienced ARE. All 3 rejecting patients in DBMI group were negative for DSA and positive for non-DSA. The lower titer of post-transplant anti-HLA antibodies were shown in DBMI patients compared to pre-transplantation titer. Additionally, the average serum creatinine levels during one year follow up and even in those patients with ARE were lower compared to controls. Con-clusion: Our findings reveal an association between pre- and post-transplant anti-HLA an-tibodies, and ARE and also early allograft dysfunction. It suggests that lower incidence of ARE, undetectable DSA, lower titer of antibodies concomitant with a decrease in serum creatinine level, better allograft function and lower percentages of PRA in DBMI patients, could be the probable manifestations of partial hypo-responsiveness against allografts.