title: A cell-free Salmonella typhimurium extract induces inhibition of tyrosine phosphorylation in murine splenic T-lymphocytes.
abstract: In a previous study, we observed that suppression of T-cell proliferation induced by Salmonella infection is associated with inhibition of tyrosine phosphorylation in T-cells, and that a cell-free Salmonella typhimurium LT2 extract (LT2 extract) also suppressed mitogen-induced T-cell proliferation. In the present study, therefore, we attempted to clarify whether the T-cell suppression induced by LT2 extract involved inhibition of tyrosine phosphorylation in T-cells. Western blotting using anti-phosphotyrosine antibodies showed that the mitogen-induced tyrosine phosphorylation of 120-, 106-, 94-, 76-, 68-, 57- and 36-kDa proteins in murine splenic T-cells was inhibited by treatment with LT2 extract. These results suggest that the suppression of T-cell proliferation induced by LT2 extract is also associated with inhibition of tyrosine phosphorylation in T-cells.
authors.affiliation: Department of Microbiology, Meiji College of Pharmacy, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Matsui
authors.forename: T
authors.initials: T
authors.lastname: Arai
mesh_terms: D000818:Animals; D002458:Cell Fractionation; D003208:Concanavalin A; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D010766:Phosphorylation / Q000187:drug effects; D019000:Phosphotyrosine / Q000037:antagonists & inhibitors / Q000276:immunology* / Q000378:metabolism*; D010835:Phytohemagglutinins; D012486:Salmonella typhimurium / Q000737:chemistry / Q000276:immunology*; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*
chemical_list: D007166:Immunosuppressive Agents; D010835:Phytohemagglutinins; D003208:Concanavalin A; D019000:Phosphotyrosine