Abstract 17151: The Impact of Non-HLA Antibodies on Cardiac Allograft Vasculopathy
Objective: Cardiacallograft vasculopathy (CAV) is a major therapeutic challenge, occurring over 50% in heart transplant (HTx) recipients in the first years. It is known that antibodies against human leukocyte antigens (HLA) could trigger CAV. Furthermore, non-HLA antibodies against antigens like major histocompatibility complex class I-related chain A (MICA), angiotensin type 1 receptor (AT1R) or endothelin receptor A (ETAR), which gain in importance as modulators of allograft function Thus, in this study we investigated the influence of both HLA and non-HLA antibodies on the incidence of CAV.
Methods: Sera of 116 HTx recipients were screened post-transplantation for MICA, HLA class I and class II antibodies by Luminex-technology and for AT1R and ETAR antibodies by ELISA. Coronary angiography was performed to diagnose CAV according to ISHLT guidelines. For statistical analysis gender, age, status of CAV, PRA level before HTx and the number of blood transfusions was documented.
Results: Overall 38% of the HTx recipients (n=44) developed CAV. There was no difference between CAV negative and positive HTx recipients regarding gender, age, PRA level or number of blood transfusions. In total HTx recipients developed antibodies against HLA (12.9%) to a lower extend than against non-HLA antigens, especially against AT1R (35.3%) and ETAR (47.4%). CAV appeared in 27.1% of recipients with non-HLA antibodies, whereas 5.8% of the recipients with HLA antibodies developed CAV. Significant more recipients with CAV were positive for AT1R (30.2%) and ETAR (37.2%) antibodies compared to CAV-positive recipients that were positive for HLA class I (2.3%), HLA class II (9.3%) and MICA (13.9%) antibodies (p<0.05). Furthermore, recipients with non-HLA antibodies developed CAV significant (p<0.05) earlier (73.7±47.4mo) than recipients without these antibodies (85.5±50.6mo).
Conclusions: HTx recipients with CAV possess a higher frequency for positive detection of non-HLA antibodies, especially against AT1R and ETAR. Additionally, non-HLA antibodies are linked to earlier incidence of CAV after HTx. The screening of HLA and especially of non-HLA antibodies after HTx is recommended to identify patients with an increased risk for CAV.
- © 2012 by American Heart Association, Inc.