Frequency analyses of human cytomegalovirus specific CD8(+) T cell in kidney transplantation

Abstract

To establish a new detection method for cytomegalovirus (CMV) specific cytotoxic CD8(+)T cells and examine its proportion and significance in peripheral blood from kidney transplant recipients. A total of 30 recipients of kidney transplantation from January 2009 to December 2010 for the first time were enrolled. And 10 healthy volunteers were selected as health control group. Tetramer technology was applied. The proportions of CMV antigen specific T cells expressed in each group were detected directly by flow cytometry. The positive rate of CMV antigen specific CTL, CMV-pp65 specific CD8(+)T cell was between 0.16%-7.21% in kidney transplant recipients (n = 30) and health control group (n = 10). The proportions of CMV antigen specific CTL were 2.95% ± 0.62% in CMV+ group. And it was significantly higher than that in CMV-group (1.17% ± 0.45%) and health control group (0.65% ± 0.17%) (P = 0.003,0.006). In CMV+ group, the proportion of CMV antigen specific CTL was 2.95% ± 0.62% in CMV-pp65 positive phase and decreased significantly to 1.50% ± 0.32% after turning into negative phase. In CMV+ group (n = 15), the proportion of CMV antigen specific CTL was positively related with the number of CMV-pp65 positive cells (Pearson test, r = 0.871, P < 0.01). The proportion of specific CTL is an important guide for evaluating and judging the prognosis of CMV infection. And it may provide rationales for future targeted therapy in kidney transplant recipients.