title: Effect of cyclosporin A on immunity to Listeria monocytogenes.
abstract: The effect of the immunosuppressive drug cyclosporin A (CS-A) on immunity to the facultative intracellular bacterium Listeria monocytogenes was investigated in unprimed and primed mice. Different treatment protocols were followed to evaluate the time dependence of CS-A-mediated immune suppression and the effect of CS-A on immunological memory to L. monocytogenes. The effect of CS-A was observed only during and after activation of T cell-mediated immunity, whereas early resistance exerted by macrophages assessed 6 and 70 min after challenge remained unaffected. CS-A suppressed efficient elimination of L. monocytogenes even when given after day 3 of a primary infection. This contrasts with findings in other models, including viral infections, where CS-A must be administered very early in an immune response to suppress it. CS-A suppressed antibacterial resistance in mice primed at various times before challenge; suppression of protection was time dependent and was virtually complete in livers, whereas CS-A-resistant memory persisted in spleens for up to 10 months.
mesh_terms: D000818:Animals; D001770:Blood Bactericidal Activity / Q000187:drug effects; D003524:Cyclosporins / Q000008:administration & dosage / Q000494:pharmacology*; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D004334:Drug Administration Schedule; D007111:Immunity, Cellular / Q000187:drug effects; D007156:Immunologic Memory / Q000187:drug effects; D007376:Interleukin-2 / Q000494:pharmacology; D008088:Listeriosis / Q000276:immunology*; D008264:Macrophages / Q000276:immunology; D051379:Mice; D013601:T-Lymphocytes / Q000276:immunology*; D014616:Vaccinia virus / Q000276:immunology
chemical_list: D003524:Cyclosporins; D007376:Interleukin-2