Objectives: Cytotoxic T-lymphocyte antigen 4 (CTLA4) has a critical role in the down-regulation of the immune response. We retrospectively examined the association between acute rejection and the single nucleotide polymorphism A/G in the CTLA-4 CT60 gene in liver transplant recipients.
Materials and methods: Fifty-one liver transplant recipients with at least 3 months' follow-up were selected and genotyped for CTLA-4 CT60 polymorphism (HpyCH4 IV). The association of each genotype with allograft acute rejection was evaluated.
Results: The mean age of patients was 27.9 +/- 15.17 years (minimum, 1 year, maximum, 55 years), with 39% male and 61% female. Overall, 17 recipients (33.3%) experienced acute rejection within the first 3 months after a liver transplant. In our study, 50% of the patients (n=26) have G/A , 31% (n=16) have A/A, and 17% have G/G genotypes (n=9). Distribution of alleles was not different according to underlying liver disease. There also was no difference in sex, age, and distributions of CTLA-4 CT60 alleles with acute rejection episodes.
Conclusions: CT60 A/G dimorphism within the 3'-UTR of CTLA4 gene does not influence acute rejection development in liver transplant. However, organ rejection is determined by a combination of several genetic traits rather than a single gene. Therefore, more studies with larger patient numbers are necessary to investigate the effect of combinations of genetic phenotypes involved in this process.