title: Ex vivo generation of human cytomegalovirus-specific cytotoxic T cells by peptide-pulsed dendritic cells.
abstract: Adoptive transfer of donor-derived human cytomegalovirus (HCMV)-specific T-cell clones can restore protective immunity after stem cell transplantation. Ex vivo induction of HCMV-specific T cells using HCMV-infected fibroblasts as stimulator cells confines this approach to HCMV-seropositive donors and requires the presence of infectious virus during the stimulation procedure. In this study, we describe a potential alternative strategy to generate HCMV-specific T cells ex vivo for adoptive immunotherapy. Generation of HCMV-specific cytotoxic T lymphocytes (CTLs) ex vivo was investigated using peptide-pulsed dendritic cells as antigen-presenting cells. HCMV-specific T cells were generated and sufficiently expanded for adoptive immunotherapy in 6 out of 14 HCMV-seropositive and 2 out of 11 HCMV-seronegative donors. The CTLs recognized HCMV-infected autologous fibroblasts. No lysis was observed with either non-infected autologous or HLA-mismatched infected fibroblasts. Staining with tetrameric HLA/peptide complexes revealed significant enrichment for peptide-specific T cells of up to 28% and > 90% of CD8(+) T cells after three and five specific stimulations respectively. In addition, the expansion rates indicated that ex vivo generation of > 1 x 10(9) HCMV-specific T cells was possible after 6--7 weeks when cultures were initiated with 1--5 x 10(6) responder cells. Thus, the approach with peptide-pulsed DCs to generate HCMV-specific CTLs is feasible for clinical application after allogeneic stem cell transplantation.
authors.affiliation: Medizinische Klinik II, Eberhard-Karls-Universität Tübingen, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Kleihauer
authors.forename: U
authors.initials: U
authors.lastname: Grigoleit
authors.forename: H
authors.initials: H
authors.lastname: Hebart
authors.forename: A
authors.initials: A
authors.lastname: Moris
authors.forename: P
authors.initials: P
authors.lastname: Brossart
authors.forename: A
authors.initials: A
authors.lastname: Muhm
authors.forename: S
authors.initials: S
authors.lastname: Stevanovic
authors.forename: H G
authors.initials: HG
authors.lastname: Rammensee
authors.forename: C
authors.initials: C
authors.lastname: Sinzger
authors.forename: S
authors.initials: S
authors.lastname: Riegler
authors.forename: G
authors.initials: G
authors.lastname: Jahn
authors.forename: L
authors.initials: L
authors.lastname: Kanz
authors.forename: H
authors.initials: H
authors.lastname: Einsele
mesh_terms: D000956:Antigens, Viral / Q000494:pharmacology*; D002460:Cell Line; D003586:Cytomegalovirus Infections / Q000276:immunology*; D003713:Dendritic Cells / Q000276:immunology*; D005347:Fibroblasts / Q000276:immunology; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D016219:Immunotherapy, Adoptive; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014184:Transplantation, Homologous
chemical_list: D000956:Antigens, Viral