A deeper understanding of the association between CTLA4 +49A/G and acute rejection in renal transplantation: An updated meta-analysis

Abstract

To reevaluate the association between the costimulatory molecule cytotoxic T lymphocyte-associated antigen4 (CTLA4) single nucleotide polymorphism (SNP) +49A/G and acute rejection (AR) in renal transplantation, nine studies published before June 2013 were analyzed. Meta-analysis and cumulative meta-analysis (metacum) were performed for each genotype in a random/fixed effect model. The combined odds ratios (OR) with 95% confidence intervals (CI) were calculated to estimate the strength of the association. In the sensitivity analysis, a single study involved in the meta-analysis was deleted each time to investigate the influence of the individual data sets on the pooled ORs. Meta-analysis regression was used for some influence factors, such as year of publication, total number in each group (AR group and control group), ethnicity, the ratio of GG to GA+AA, the ratio of G to A in CTLA4 +49A/G. Overall, a significant correlation was noted between the CTLA4 SNP (+49A/G) and the risk of AR (for GG vs. AG+AA: OR=1.35, 95% CI=1.05-1.73, p=0.02; for G vs. A: OR=1.21, 95% CI=1.03-1.42, p=0.02), especially in the Asian subgroup (for GG vs. AG+AA: OR=1.79, 95% CI=1.15-2.78, p=0.009; for G vs. A: OR=1.47, 95% CI=1.04-2.07, p=0.03). Of the influence factors, the ratio of GG to GA+AA (p=0.046) and the ratio of G to A (p=0.017) were significant factors. In conclusion, our results suggest that CTLA4 +49A/G contribute to the risk of AR following renal transplantation.