title: Augmented induction of interferons during Listeria monocytogenes infection.
abstract: Mice infected iv with an immunizing dose of the gram-positive bacterium, Listeria monocytogenes, produced circulating interferon (IFN) during the inductive phase of the immune response to Listeria. Listeria infection also dramatically altered the host's responsiveness to IFN-inducing agents. Within 24 hr of infection, mice acquired a 50-fold greater than normal capacity to produce the IFN alpha and/or IFN beta classes (IFN alpha/beta) following iv injection of endotoxin. Serum levels of IFN alpha/beta peaked by 2 hr, after which high levels of IFN gamma were detected in the sera of Listeria-infected mice given the B cell mitogen. Similar studies carried out with the interferon-inducing agent polyinosinic-polycytidylic acid (poly(I).poly(C) revealed that mice infected for 24 hr produced only 4-8 times more IFN alpha/beta than did noninfected mice. Unlike endotoxin, however, poly(I).poly(C) did not induce IFN gamma in Listeria-infected animals.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004731:Endotoxins / Q000494:pharmacology; D007370:Interferon Type I / Q000096:biosynthesis* / Q000097:blood / Q000276:immunology; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000097:blood / Q000276:immunology; D008088:Listeriosis / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D011070:Poly I-C / Q000494:pharmacology; D012477:Salmonella enteritidis; D013154:Spleen; D013601:T-Lymphocytes / Q000276:immunology; D013997:Time Factors
chemical_list: D004731:Endotoxins; D007370:Interferon Type I; D007371:Interferon-gamma; D011070:Poly I-C