Prophylactic infusion of cytomegalovirus-specific cytotoxic T lymphocytes stimulated with Ad5f35pp65 gene-modified dendritic cells after allogeneic hemopoietic stem cell transplantation.

Cytomegalovirus (CMV) and its therapy continue to contribute to morbidity and mortality in hemopoietic stem cell transplantation (HSCT). Many studies have demonstrated the feasibility of in vitro generation of CMV-specific T cells for adoptive immunotherapy of CMV. Few clinical trials have been performed showing the safety and efficacy of this approach in vivo. In this study, donor-derived, CMV-specific T cells were generated for 12 adult HSCT patients by stimulation with dendritic cells transduced with an adenoviral vector encoding the CMV-pp65 protein. Patients received a prophylactic infusion of T cells after day 28 after HSCT. There were no infusion related adverse events. CMV DNAemia was detected in 4 patients after infusion but was of low level. No patient required CMV-specific pharmacotherapy. Immune reconstitution to CMV was demonstrated by enzyme linked immunospot assay in all recipients with rapid increases in predominantly CMV-pp65 directed immunity in 5. Rates of graft-versus-host disease, infection, and death were not increased compared with expected. These results add to the growing evidence of the safety and efficacy of immunotherapy of CMV in HSCT, supporting its more widespread use. This study was registered at www.anzctr.org.au as #ACTRN12605000213640.