title: Tetranactin, a macrotetrolide antibiotic, suppresses in vitro proliferation of human lymphocytes and generation of cytotoxicity.
abstract: Tetranactin, a hydrophobic cyclic antibiotic produced by Streptomyces aureus, has previously been shown to suppress in vitro activation of rat lymphocytes by concanavalin A as well as the onset of experimental autoimmune uveoretinitis in Lewis rats. Here we report the effects of tetranactin on human T and NK lymphocytes in vitro. Tetranactin, at concentrations up to 100 ng/ml, was not toxic to human lymphocytes but completely abrogated the proliferation of human T lymphocytes in response to allogeneic cells in mixed lymphocyte cultures. Tetranactin also blocked the initiation of proliferation in response to interleukin-2, but did not block proliferation of interleukin-2-activated cells. Tetranactin also blocked generation of cytotoxic T lymphocytes and activated killer cells in the mixed lymphocyte culture. However, up to 100 ng/ml tetranactin did not alter the lytic activity of cytotoxic T or NK lymphocytes generated in its absence. The ability of low doses of tetranactin to block the induction of lymphoproliferation is similar to the action of cyclosporin A. Since cyclosporin A is also a cyclic hydrophobic molecule, the immunosuppressive actions of these two agents may involve a similar mechanism.
authors.affiliation: Department of Chemistry, Oakland University, Rochester, MI 48309.
authors.forename: D M
authors.initials: DM
authors.lastname: Callewaert
authors.forename: G
authors.initials: G
authors.lastname: Radcliff
authors.forename: Y
authors.initials: Y
authors.lastname: Tanouchi
authors.forename: H
authors.initials: H
authors.lastname: Shichi
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D006801:Humans; D007166:Immunosuppressive Agents; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects*; D007959:Lymphocyte Culture Test, Mixed; D008875:Middle Aged; D011714:Pyrans / Q000494:pharmacology*; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000276:immunology
chemical_list: D000900:Anti-Bacterial Agents; D007166:Immunosuppressive Agents; D007376:Interleukin-2; D011714:Pyrans; C003417:tetranactin