P208 Comparison of two assays for CMV specific cell mediated immunity in the recipients of liver transplantation

Abstract

Aim To prevent serious problem due to cytomegalovirus (CMV) infection, antiviral prophylaxis is commonly used in recipients of solid-organ transplants. To predict which patient will develop CMV disease, CMV-specific cell-mediated immunity can be measured by Quantiferon-CMV, ELISpot assay, cytokine profiling, intracellular cytokine staining and tetramer staining. We were comparing Quantiferon-CMV and ELISpot assay in the recipient of liver transplantation in Korea, in which most people are seropositive. Methods We prospectively included 35 patients who will receive antiviral prophylaxis for liver transplantation in a tertiary university hospital. We had tested interferon-gamma level following in vitro stimulation with CMV antigen using two assays – EliSpot IFN-γ CMVspot (CMVspot) (Autoimmun Diagnostika, Germany) and Quantiferon-CMV (QF-CMV) (Qiagen, Australia). Blood samples of recipient collected before liver transplantation and CMVspot, CF-CMV and CMV IgM/IgG assay (BioMerieux, Germany) were performed simultaneously. For detection of CMV viremia, real-time PCR was performed using CMV R-gene kit (BioMerieux, France). The testing and interpretation were performed according to the manufacturer’s recommendation. Results The agreement rate of two assays was overall 51.5%. Although CMVspot results showed 32 recipients has CMV-specific cell-mediated immunity, 17 patients show reactive results in the QF-CMV assay. The 28 patients show the reactive result of CMVspot pp65 and the 13 patients show reactive results of CMVspot IE-1. Two samples were failing during the process of CMVspot on the sample reception and interpretation step and seven samples were interpreted indeterminate because of low mitogen reactivity in QF-CMV. All patients had a positive result of CMV IgG before transplantation and 16 patients had CMV viremia episode after transplantation. Conclusions To choose the method for testing cell-mediated immunity for CMV, laboratory have to concern about the characteristics of assays and regional seropositive prevalence. The results of two commercial assays can be different at one time for testing. Further evaluation was proceeding for accurate prediction of CMV disease after solid-organ transplantation.