T-cell therapy for cytomegalovirus infection

Abstract

Human cytomegalovirus (CMV) reactivation and disease remains one of the major complications after allogeneic haemopoietic stem cell transplantation. Cell-mediated immunity is essential in counteracting CMV infection as evident by detection of high frequencies of CMV-specific CD8 and CD4 lymphocytes among the healthy CMV-seropositive individuals. Adoptive transfer of CMV-specific T cells to speed up reconstitution of CMV-specific immunity potentially offers clinical protection and reduces drug toxicities as well as outgrowth of drug-resistant strains from prolonged antiviral therapy. Different strategies to generate CMV-specific T cell have been explored. Similarly, vast diversities in term of cell dose and composition of the cellular product have been infused into small cohorts of patients. To date, a number of phase I/II clinical trials have demonstrated the feasibility of adoptive transferred CMV-specific T cells as prophylaxis, pre-emptive or therapeutic measure. In general, all these strategies showed variable degrees of efficacy without obvious adverse event particularly with regard to the induction of graft-versus-host disease. In this review, we would like to give a comprehensive synopsis regarding therapeutic application of CMV-specific T cells in fighting CMV infection.