title: Antitumor effects of the fibroblasts transfected TNF-alpha gene and its mutants.
abstract: To compare the anti-tumor effects of transmembrane TNF-alpha (TM-TNF) and secreted TNF-alpha (S-TNF) in vivo, mouse fibroblasts NIH3T3 were transfected separately with three types of retrovirus containing wild type TNF-alpha (Wt-TNF), TM-TNF mutant (TM-TNFm), S-TNF mutant (S-TNFm). Southern blot, RT-PCR, FACS and bioassay were used to investigate TNF-alpha gene integration, expression and its biological activity. It was found that both fixed cells and supernatant of NIH3T3/Wt-TNF, the fixed cells of NIH3T3/TM-TNFm and the supernatant of NIH3T3/S-TNFm could express high level of TNF-alpha or its mutants and effectively kill H22 in vitro. The transfected NIH3T3 were separately injected into the mice at the sites of H22 tumor cell inoculation according to a ratio of 5:1 or 1:1 (effector/target cells, E/T) after the third day of H22 challenge, respectively. At the E/T = 5:1, the NIH3T3/TM-TNFm induced the highest tumor regression, while NIH3T3/S-TNFm exerted the strongest tumor depressing effect at the E/T = 1:1 in vivo. No obvious side effects were noted throughout the course of treatment. The results suggest that both TM-TNF and S-TNF could cause tumor regression. The anti-tumor effect of TM-TNF would be more powerful and safe than that of S-TNF at the proper E/T ratio.
authors.affiliation: Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030.
authors.forename: Qingfen
authors.initials: Q
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Zhuoya
authors.initials: Z
authors.lastname: Li
authors.forename: Feili
authors.initials: F
authors.lastname: Gong
authors.forename: Wei
authors.initials: W
authors.lastname: Feng
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Jiang
authors.forename: Ping
authors.initials: P
authors.lastname: Xiong
mesh_terms: D016475:3T3 Cells; D000260:Adenoviruses, Human / Q000235:genetics; D000818:Animals; D003602:Cytotoxicity, Immunologic / Q000276:immunology; D005347:Fibroblasts / Q000166:cytology / Q000276:immunology*; D008114:Liver Neoplasms, Experimental / Q000276:immunology* / Q000473:pathology; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D009154:Mutation; D014162:Transfection; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics* / Q000276:immunology / Q000378:metabolism
chemical_list: D008565:Membrane Proteins; D014409:Tumor Necrosis Factor-alpha