Proliferative T cell responses to four human cytomegalovirus-specific proteins in healthy subjects and solid organ transplant recipients

Abstract

It is still poorly understood which of the cytomegalovirus (CMV)-induced proteins are important for the host's cellular immunity during active infection and for establishing latency. To answer this question, in vitro proliferative T cell responses to four recombinant CMV proteins were compared and compared with responses to CMV-infected fibroblasts in immunocompetent healthy CMV-seropositive subjects and immunocompromised organ transplant recipients. The proteins studied were the lower matrix protein pp65 (ppUL83), the DNA-binding protein p52 (ppUL44), and the two immediate-early proteins IE1 (UL123) and IE2 (UL122). In healthy persons, pp65 was the most important protein with respect to its ability to induce a proliferative T cell response. In transplant recipients, severe suppression of the responses to these CMV proteins was found. This finding may be clinically relevant in view of the occurrence and course of CMV infection in these patients.