Expression characteristics of major histocompatibility complex class I-related chain A antibodies and immunoadsorption effect in sensitized recipients of kidney transplantation / 中华医学杂志(英文版)

ABSTRACT

<p><b>BACKGROUND</b>Sensitized recipients have a high risk of immunological graft loss due to hyperacute rejection and/or accelerated acute rejection. The presence of major histocompatibility complex class I-related chain A (MICA) antibodies has also been described associated with an increased rate of kidney-allograft rejection. The aim of this study was to describe the expression of MICA antibodies in sensitized recipients of renal transplantation and evaluate its influence on the kidney transplantation recipients.</p><p><b>METHODS</b>A total of 29 sensitized recipients were included in this study. All patients received the MICA antibodies detection before and after protein A immunoadsorption. Panel reactive antibody (PRA), HLA-matches, acute rejection and postoperative one to four-week serum creatinine level were also collected and analyzed, respectively. No prisoners were used in this study.</p><p><b>RESULTS</b>Eight patients (27.6%) in all 29 sensitized recipients expressed the MICA antibodies but did not show higher acute rejection rate than the non-expressed patients (3/8, 37.5% vs. 8/21, 38.1%; P = 1.000). Recipients with PRA > 40% showed higher expression levels of MICA antibodies than the recipients with PRA < 40% (7/16, 43.8% vs. 1/13, 8.3%; P = 0.044). HLA mismatch did not have any effect on the expression of MICA antibodies (P = 1.000). MICA antibodies positive group had higher serum creatinine level than the control in postoperative one week ((135.4 ± 21.4) µmol/L vs. (108.6 ± 31.6) µmol/L, P = 0.036), but no significant difference in postoperative four weeks ((89.0 ± 17.1) µmol/L vs. (77.1 ± 15.9) µmol/L, P = 0.089). MICA antibodies decreased significantly after protein A immunoadsorption.</p><p><b>CONCLUSIONS</b>MICA antibodies increase in the sensitized recipients, which have significant effects on the function of allograft in early postoperative period. Protein A immunoadsorption can decrease MICA antibodies effectively in sensitized recipients.</p>