Inhibitory Effect Of Polysaccharide Sulfate Against Superantigen And Anti-Tumor Of Superantigen

Objectives: To find out the agent which could protected superantigen(SEB) induced lethal shock in mice and to evaluate the tumoricidal effect of staphylococcal enterotoxin C (SEC) in vitro and in vivo..Methods: 20 mg of D-gal was intraperitoneal (i.p.) injected to BALB/c mice 30 minutes before challenge with SEB, and inoculated with Polysaccharide sulfate (PSS) (10mg/animal) in SEB challenged 0, 1, 2 and 4 hrs. The survival ratio of were checked twice daily until 96 hours post-SEB injection. The TNF-αor IFN-γlevels were determined using ELISA .The p38 activity was determined using western blotting. To evaluate SEC as an anti-tumor agent in vitro and in vivo. SEC activated peripheral blood monouclear cells, PBMCs, were able to induce cytotoxicity towards various human carcinoma cells in co-culture experiments in vitro at very low concentrations, check cells(BEL-7402, SMMC-7721, HepG-2, HT-29, BGC-823, GLC-82, Hela, KB) by MTT. Treatment of C57BL/6 mice and rabbits systematicly with SEC in vivo, check tumor outgrow.Results: In section on Superantigens are viral or bacterial proteins that elicit massive T-cell proliferation. Staphylococcal enterotoxin B (SEB) is a Staphylococcus aureus produced superantigen, inducing strong activation of T lymphocytes even at very low concentrations SEB together with several other Staphylococcal and Streptococcal toxins belong to the pyrogenic toxin superantigens family. In section two, treatment of C57BL/6 mice systematicly with SEC resulted in a statistically significant decrease in tumor outgrowth. Treatment of rabbits also resulted in decrease in tumor outgrowth. Moreover, the therapy groups showed tumor necrosis and strong infiltration of lymphocytes in tumor area and prevented metastasis of tumor cell in contrast to control group.CONCLUSION: These experiments indicated that PSS could be a potentialdrug for treatment of SEB induced shock. PSS lowers serum cytokine levels induced by SEB. SEC activated PBMCs were able to induce cytotoxicity towards various human carcinoma cells in co-culture experiments in vitro at very low concentrations. These preclinical results suggested that SEC might be a promising candidate as an anti-cancer agent for further clinical evaluation.