The Impact of HLA-G and HLA-E Polymorphisms on CMV Reinfection in Liver Transplant Recipients.

Background: Cytomegalovirus (CMV) reinfection in transplant patients has been associated with graft loss and decreased patient survival. In this regard, the HLA-G molecule has the immunomodulatory characteristic and its soluble isoforms have important roles in immunity to viruses. The 14bp insertion/deletion polymorphism impacts HLA-G mRNA stability. Regarding the HLA-E molecule, two nonsynonymous alleles, HLA-E*0101, and HLA-E*0103 are different in their functions including the affinity of the relative peptide.

Objective: To explore the possible link between HLA-G and HLA-E polymorphisms with CMV reinfection among liver transplant recipients (LTRs).

Methods: In this study, a total of 140 liver transplantations were performed; of which 70 CMV-reactivated LTRs and 70 CMV non-reactivated ones were recruited. The cut-off value of CMV DNA was determined to be 100 copies/mL. PCR evaluated different genotypes for HLA-G and ARMS-PCR for HLA-E*0101 and *0103.

Results: Neither the HLA-G genotypes (-14 bp/-14bp and +14bp/+14 bp homozygous genotypes with the p-values: 0.43, and 0.13, respectively +14 bp⁄-14 bp heterozygous genotype with p-value: 0.49) nor the HLA-E genotypes (HLA-E*0101/0103, HLA-E*0101/0101, and HLA-E*0103/0103 with the p-values: 0.152, 0.249, and 0.391, respectively) had any association with CMV reinfection in the LTRs.

Conclusion: No difference was observed in the HLA-E and HLA-G genotype frequencies between our studied groups. Further studies are needed to explore other genetic variations and evaluate soluble HLA-G and HLA-E levels in the transplant population.