title: Immune deviation and Fas-mediated deletion limit antitumor activity after multiple dendritic cell vaccinations in mice.
abstract: Genetic immunization with a single injection of dendritic cells (DCs) expressing a model melanoma antigen generates antigen-specific, MHC-restricted, protective immune responses. After initiating the immune response, additional vaccinations may increase the protection or conversely downregulate the immune response. Groups of mice were vaccinated several times with DCs transduced with the MART-1 gene, and the anti-tumor protection was compared with that of mice receiving a single vaccination. C3H mice had poorer protection from a syngeneic MART-1-expressing tumor challenge with multiple vaccinations. This was accompanied by lower levels of splenic CTL effectors and a shift from a type 1 to a type 2 cytokine profile. On the contrary, multiple vaccinations in C57BL/6 mice generated greater in vivo antitumor protection with no decrease in splenic CTLs and no cytokine shift. Antiadenoviral humoral or cellular immune responses did not seem to contribute to these effects. When studies were performed in Fas receptor-negative C3H.(lpr) mice, the adverse effect of multiple vaccinations disappeared, and there was no cytokine shift pattern. In conclusion, C3H mice but not C57BL/6 mice receiving multiple vaccinations with DCs expressing the MART-1 tumor antigen show decreased protection associated with deviation from a type 1 to a type 2 cytokine response attributable to a Fas-receptor mediated clearance of antigen-specific IFN-gamma-producing cells.
authors.affiliation: Division of Surgical Oncology, University of California at Los Angeles, 90095, USA.
authors.forename: A
authors.initials: A
authors.lastname: Ribas
authors.forename: L H
authors.initials: LH
authors.lastname: Butterfield
authors.forename: B
authors.initials: B
authors.lastname: Hu
authors.forename: V B
authors.initials: VB
authors.lastname: Dissette
authors.forename: W S
authors.initials: WS
authors.lastname: Meng
authors.forename: A
authors.initials: A
authors.lastname: Koh
authors.forename: K J
authors.initials: KJ
authors.lastname: Andrews
authors.forename: M
authors.initials: M
authors.lastname: Lee
authors.forename: S N
authors.initials: SN
authors.lastname: Amar
authors.forename: J A
authors.initials: JA
authors.lastname: Glaspy
authors.forename: W H
authors.initials: WH
authors.lastname: McBride
authors.forename: J S
authors.initials: JS
authors.lastname: Economou
mesh_terms: D000256:Adenoviridae / Q000235:genetics / Q000276:immunology; D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology; D000956:Antigens, Viral / Q000276:immunology; D019496:Cancer Vaccines / Q000008:administration & dosage / Q000276:immunology*; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism / Q000637:transplantation; D005260:Female; D005822:Genetic Vectors / Q000235:genetics / Q000276:immunology; D007115:Immunization Schedule; D007371:Interferon-gamma / Q000276:immunology; D058965:MART-1 Antigen; D008285:Major Histocompatibility Complex / Q000276:immunology; D008546:Melanoma, Experimental / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D009154:Mutation / Q000235:genetics; D009363:Neoplasm Proteins / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D014407:Tumor Cells, Cultured; D014611:Vaccination; D019014:fas Receptor / Q000235:genetics / Q000502:physiology*
chemical_list: D000951:Antigens, Neoplasm; D000956:Antigens, Viral; D019496:Cancer Vaccines; D058965:MART-1 Antigen; C548668:Mlana protein, mouse; D009363:Neoplasm Proteins; D019014:fas Receptor; D007371:Interferon-gamma