title: Benefits of gene transduction of granulocyte macrophage colony-stimulating factor in cancer vaccine using genetically modified dendritic cells.
abstract: Granulocyte macrophage colony-stimulating factor (GM-CSF) is a key cytokine for the generation and stimulation of dendritic cells (DCs), and it may also play a pivotal role in promoting the survival of DCs. In this study, the feasibility of creating a cancer vaccine using DCs adenovirally transduced with the carcinoembryonic antigen (CEA) gene and the GM-CSF gene was examined. In addition, the effect of the co-transduction of GM-CSF gene on the lifespan of these genetically modified DCs was determined. A cytotoxic assay using peripheral blood mononuclear cell (PBMC)-derived cytotoxic T lymphocytes (CTLs) was performed in a 4-h 51Cr release assay. The apoptosis of DCs was examined by TdT-mediated dUTP-FITC nick end labeling (TUNEL) assay. CEA-specific CTLs were generated from PBMCs stimulated with genetically modified DCs expressing CEA. The cytotoxicity of these CTLs was augmented by co-transduction of DCs with the GM-CSF gene. Co-transduction of the GM-CSF gene into DCs inhibited apoptosis of these DCs themselves via up-regulation of Bcl-x(L) expression, leading to the extension of the lifespan of these DCs. Furthermore, the transduction of the GM-CSF gene into DCs also suppressed the incidence of apoptosis of DCs induced by transforming growth factor-beta1 (TGFbeta-1). Immunotherapy using these genetically modified DCs may therefore be useful with several advantages as follows: i) adenoviral toxicity to DCs can be reduced; ii) the lifespan of vaccinated DCs can be prolonged; and iii) GM-CSF may protect DCs from apoptosis induced by tumor-derived TGFbeta-1 in the regional lymph nodes.
authors.affiliation: Second Department of Surgery, Wakayama Medical University, School of Medicine, Kimiidera, Wakayama 641-8510, Japan.
authors.forename: Toshiyasu
authors.initials: T
authors.lastname: Ojima
authors.forename: Makoto
authors.initials: M
authors.lastname: Iwahashi
authors.forename: Masaki
authors.initials: M
authors.lastname: Nakamura
authors.forename: Kenji
authors.initials: K
authors.lastname: Matsuda
authors.forename: Mikihito
authors.initials: M
authors.lastname: Nakamori
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ueda
authors.forename: Teiji
authors.initials: T
authors.lastname: Naka
authors.forename: Masahiro
authors.initials: M
authors.lastname: Katsuda
authors.forename: Motoki
authors.initials: M
authors.lastname: Miyazawa
authors.forename: Hiroki
authors.initials: H
authors.lastname: Yamaue
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D017209:Apoptosis / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D019496:Cancer Vaccines / Q000276:immunology / Q000627:therapeutic use*; D002272:Carcinoembryonic Antigen / Q000235:genetics / Q000276:immunology / Q000627:therapeutic use; D002460:Cell Line; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism / Q000637:transplantation; D004797:Enzyme-Linked Immunosorbent Assay; D005240:Feasibility Studies; D005434:Flow Cytometry; D005822:Genetic Vectors / Q000235:genetics; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics* / Q000276:immunology / Q000627:therapeutic use; D006801:Humans; D007167:Immunotherapy; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014161:Transduction, Genetic; D014162:Transfection