title: Priming for T-cell-mediated rejection of established tumors by cutaneous DNA immunization.
abstract: DNA immunization has been shown to elicit both antibody and CTL responses against antigens expressed by infectious organisms. Because CTL responses have been implicated in rejection of cancer, we investigated whether DNA immunization by particle bombardment using a gene gun could induce CTL responses that were capable of rejecting tumors in mice. DNA immunization by particle bombardment using genes encoding beta-galactosidase and ovalbumin primed mice to generate CTLs in two genetic backgrounds (DBA/2 and C57BL/6 strains, respectively). DNA immunization was more potent in inducing CTLs than immunization with an optimized regimen of ovalbumin peptide plus immune adjuvant. Immunity induced by DNA immunization protected mice against s.c. challenge with tumors expressing the beta-galactosidase antigen. Tumors were rejected even when DNA immunization was started 3 or 7 days after tumor challenge as tumors were becoming established. Tumor rejection required CD8(+) T cells, confirming a role for CTLs in vivo. These studies show that DNA immunization by particle bombardment can efficiently induce CTL responses that are capable of rejecting even established tumors.
authors.affiliation: The Immunology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
authors.forename: H M
authors.initials: HM
authors.lastname: Ross
authors.forename: L W
authors.initials: LW
authors.lastname: Weber
authors.forename: S
authors.initials: S
authors.lastname: Wang
authors.forename: G
authors.initials: G
authors.lastname: Piskun
authors.forename: R
authors.initials: R
authors.lastname: Dyall
authors.forename: P
authors.initials: P
authors.lastname: Song
authors.forename: Y
authors.initials: Y
authors.lastname: Takechi
authors.forename: J
authors.initials: J
authors.lastname: Nikolić-Zugić
authors.forename: A N
authors.initials: AN
authors.lastname: Houghton
authors.forename: J J
authors.initials: JJ
authors.lastname: Lewis
mesh_terms: D000818:Animals; D019470:Biolistics; D019496:Cancer Vaccines / Q000008:administration & dosage; D007279:Injections, Subcutaneous; D012515:Mast-Cell Sarcoma / Q000276:immunology / Q000628:therapy*; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D010047:Ovalbumin / Q000235:genetics / Q000276:immunology; D011994:Recombinant Proteins / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014162:Transfection; D014407:Tumor Cells, Cultured; D019444:Vaccines, DNA / Q000008:administration & dosage; D001616:beta-Galactosidase / Q000235:genetics / Q000276:immunology
chemical_list: D019496:Cancer Vaccines; D011994:Recombinant Proteins; D019444:Vaccines, DNA; D010047:Ovalbumin; D001616:beta-Galactosidase