The influence of CTLA-4 single nucleotide polymorphisms on acute kidney allograft rejection in Turkish patients.

Cytotoxic T-lymphocyte antigen-4 (CTLA-4) is a cell surface protein, which down-regulates the immune response at CTLA-4/CD28/B7 pathway. We aimed to investigate the influence of the −318C/T, +49A/G, −1661A/G and CT60A/G, and CTLA-4 gene polymorphisms on acute rejection of kidney allograft in Turkish patients. The study design was a case–control study that consists of three groups: Group 1 (n = 34) represented the kidney transplant (Ktx) recipients who experienced acute rejection, Group 2 (n = 47) was randomly assigned Ktx recipients without acute rejection, and Group 3 (n = 50) consisting of healthy volunteers to evaluate the normal genomic distribution. The polymerase chain reaction–restriction fragment length polymorphism technique was used to determine the polymorphisms. Genotype and allele frequencies among three groups denoted similar distributions for +49A/G, −1661A/G, and CT60A/G. Conversely, −318C/T genotype was three times more frequent in the acute rejection group than in the non-rejection group (OR = 3.45; 95%CI = 1.18–10.1, p = 0.015) and two times more frequent than the healthy control group (OR = 2.45; 95% CI = 0.98 – 6.11, p = 0.047). Additionally, having a T allele at −318 position was significantly associated with acute rejection (0.147 vs. 0.043, OR = 3.45; 95% CI = 1.13–10.56, p = 0.02). 318C/T gene polymorphism and T allelic variant were found to be associated with increased acute rejection risk in Turkish kidney allograft recipients.