Immunoglobulin-like receptor genotype-associated protection from cytomegalovirus infection after liver transplantation.

Background: Cytomegalovirus (CMV) is a common clinical infection especially after organ transplantation and threaten the survival of recipients. Natural killer (NK) cells play an important role in the process of CMV infection. In this study, we want to explore that if the different of killer immunoglobulin-like receptors (KIRs) of NK cells could affect CMV infection.

Methods: We study a cohort of 447 recipients after liver transplantation in our center. KIR-SSO Genotyping kit was used to detect the activated and inhibitory KIR genes. We determine the high-risk factors for CMV infection, and based on the KIR genotype, the recipients are divided into different groups, then the rate of CMV infection was analyzed.

Results: CMV infection occurred in 32/447 (7.2 %) patients in the first year after the transplant surgery. We find that recipient age, Body Mass Index (BMI), Model for End-Stage Liver Disease (MELD) score, intubation time, and occurrence of Early Allograft Dysfunction (EAD) are high-risk factors for CMV infection. Comparing with the CMV-DNA turned negative, the percentage of lymphocyte, as well as the number of lymphocytes and CD4 lymphocytes decreased when the period of receipts' CMV-DNA tested positive. The rate of CMV infection in Tel-B/X genotype group is significantly lower than A/A genotype group.

Conclusions: Our data indicates that KIR genes can affect CMV infection and provide potential clinical value following liver transplantation.