Pre-transplant serum concentrations of anti-endothelial cell antibody in panel reactive antibody negative renal recipients and its impact on acute rejection

Background: Endothelial cell antigens are important targets in acute rejection (AR). Our goal was to measure the serum concentrations of pre-transplant anti-endothelial cell antibody (AECA) in panel reactive antibody (PRA) negative recipients and its impact on AR within 6 months following renal transplantation. Methods: We retrospectively examined pre-transplant sera from 392 patients using cellular enzyme linked immunosorbent assay (ELISA) with substrate from a permanent endothelial cell line EAhy926. Equal volumes of serum from 40 healthy volunteers were mixed and used as the negative control. Results: The positive rate of AECA was 15.8%. There were no significant differences with respect to age, gender, original disease, dialysis history, immune suppressive regimen, cytomegalovirus (CMV) antigen positive rate, complement dependent cytotoxicity (CDC) level and soluble CD30 (sCD30) levels between the AECA positive group and AECA negative group. AR rate in the AECA positive group was higher than that in the AECA negative group (35.5% vs. 22.4%, p=0.023). The AECA positive patients had significantly higher rates of acute grade II T-cell mediated rejection (TMR) and acute antibody mediated rejection (AMR) compared with AECA negative patients. The concentrations of sCD30, and AECA were independent risk factors for AR within 6 months; the odds ratios were 7.005 and 2.469, respectively. Conclusions: Positive AECA was an independent risk factor for AR and appeared to correlate with relatively severe rejection subtypes. Clin Chem Lab Med 2009;47:1265-9.