ABSTRACT
CD86 is a costimulatory molecule that participates in the regulation of T-cell lymphocytes activation. Thus, we examined a genetic marker on the CD86 gene in kidney transplant outcome. In our retrospective study, 168 kidney allograft recipients were genotyped by direct sequencing. Patients were classified into 2 groups of 29 human leukocyte antigen [HLA]-identical haplotype allograft recipients and 139 recipients showing one or more mismatches in the HLA haplotype. Forty-five patients [26.8%] developed at least 1 acute rejection [AR] episode, 7 in the first and 38 in the second group. Acute rejection was associated with the presence anti-HLA antibodies before transplantation [P=.03]. The AA genotype and A allele at position+1057 in the CD86 gene were more frequent in patients without AR [9.75% and 28.5%, respectively] compared with those showing an AR [2.22% and 23.3%, respectively]. This difference was statistically significant in the anti-HLA-positive recipients, as AA frequency was 31.3% in non-AR patients and zero in AR ones [P=.04] and A allele frequency was 46.9% and 20.8%, respectively [P=.04]. Patients bearing AA genotype reached a higher graft survival time [9.84 years] than those carrying GA [8.21 years, P=.32] or GG [7.61 years, P=.72] genotypes. These results suggest that AA genotype and A allele of CD86+1057G>A polymorphism may confer a protection against acute kidney allograft rejection in Tunisian patients