title: In vivo induction of necrosis in mice fibrosarcoma via intravenous injection of type B staphylococcal enterotoxin.
abstract: The bacterial superantigen staphylococcal enterotoxin B (SEB) is a potent inducer of cytotoxic T-cell activity and cytokine production in vivo. We investigated the possibility of the therapeutic application of SEB in patients with fibrosarcoma. The anti-tumor effect of SEB in mice with inoculated fibrosarcoma (WEHI-164) was examined by intravenous (IV) and intratumoral (IT) injection and the sizes of the inoculated tumors, IFN-gamma production, and CD4+/CD8+ T cell infiltration were determined. The inoculated tumors were also examined histologically. In the mice in the IV-injected group, a significant reduction (P < 0.02) of tumor size was observed in comparison with mice in the IT-injected and control groups. Furthermore, the mice in the IV-injected group showed significantly higher levels of IFN-gamma (P < 0.009) and CD4+/CD8+ T cell infiltration when compared with the other groups (P < 0.02). A significantly higher frequency of necrosis in tumor tissues was also observed in mice in the IV-injected group (P < 0.05). Our present findings suggest that tumor cell death is caused by increased cytotoxic T-cell activity and cytokine levels in response to the IV injection of SEB and that SEB may be a good option for use as a novel therapy in patients with fibrosarcoma.
authors.affiliation: Research Center of Molecular Biology and Department of Microbiology, Baqiyatallah University of Medical Sciences, Tehran, Iran. Imanifouladi.a@gmail.com
authors.forename: Abbas Ali Imani
authors.initials: AA
authors.lastname: Fooladi
authors.forename: Morteza
authors.initials: M
authors.lastname: Sattari
authors.forename: Zuhair Mohammad
authors.initials: ZM
authors.lastname: Hassan
authors.forename: Mehdi
authors.initials: M
authors.lastname: Mahdavi
authors.forename: Taghi
authors.initials: T
authors.lastname: Azizi
authors.forename: Akira
authors.initials: A
authors.lastname: Horii
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000008:administration & dosage* / Q000276:immunology / Q000494:pharmacology; D017209:Apoptosis; D004768:Enterotoxins / Q000008:administration & dosage* / Q000276:immunology / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D005354:Fibrosarcoma / Q000276:immunology* / Q000473:pathology / Q000628:therapy*; D005434:Flow Cytometry; D020287:In Situ Nick-End Labeling; D007275:Injections, Intravenous; D007371:Interferon-gamma / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D009336:Necrosis; D018709:Statistics, Nonparametric; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D004768:Enterotoxins; D015847:Interleukin-4; C031818:enterotoxin B, staphylococcal; D007371:Interferon-gamma