Evaluation of T-Track® CMV to assess the functionality of Cytomegalovirus-reactive cell-mediated immunity in hemodialysis patients

Background Impairment of Cytomegalovirus (CMV)-specific cell-mediated immunity (CMI) by immunosuppressive therapy is a major cause for uncontrolled CMV replication and related clinical complications. Objective The aim of the study was to assess the suitability of the immune monitoring tool T-Track ® CMV to determine CMV-reactive CMI in hemodialysis patients. Study Design Positive and negative agreement of T-Track ® CMV with CMV-serology have been examined in a cohort of 124 hemodialysis patients of whom 67 (54%) revealed a positive CMV serostatus and compared with that of QuantiFERON ® -CMV and a mixture of 6 CMV iTAG tetramers. Results Positive T-Track ® CMV, QuantiFERON ® -CMV and CMV tetramer results were obtained in 60/67, 45/62 and 40/52 CMV-seropositive hemodialysis patients resulting in 89.6%, 72.6% and 76.9% positive agreement with CMV-serology, respectively. Positive T-Track ® CMV responses were dominated by pp65-reactive cells (58/67 (86.6%)), whereas IE-1 responsive cells were observed in 33/67 (49.3%) CMV-seropositive patients. T-Track ® CMV, QuantiFERON ® -CMV and CMV tetramers showed 78.9% (45/57), 87.3% (48/55) and 93.3% (42/45) negative agreement with serology respectively. Notably, T-Track ® CMV-positive tests in seronegative patients were mostly caused by IE1-reactive cells at low spot counts. Conclusion T-Track ® CMV represents a sensitive assay format, enabling functional assessment of the network of clinically relevant subpopulations of CMV-responsive cells. Thus, T-Track ® CMV may represent a valuable tool to identify patients at increased risk for CMV-related clinical complications and may help to guide personalized antiviral and immunosuppressive therapy.