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T cells made deficient in interleukin-2 production by exposure to staphylococcal enterotoxin B in vivo are primed for interferon-γ and interleukin-10 secretion

✍ Scribed by Sandrine Florquin; Zoulikka Amraoui; Michel Goldman


Publisher
John Wiley and Sons
Year
1995
Tongue
English
Weight
659 KB
Volume
25
Category
Article
ISSN
0014-2980

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✦ Synopsis


T cells made deficient in interleukin-2 production by exposure to staphylococcal enterotoxin B in vivo are primed for interferon-y and interleukin-10 secretion

The superantigen staphylococcal enterotoxin B (SEB) induces a defect in interleukin (1L)-2 production by T cells expressing specific T cell receptor Vp domains. The present study was undertaken to determine the capacity of T cells, made deficient in IL-2 production by exposure to SEB in vivo, to secrete interferon (IFN)-y and IL-10 and to induce pathology upon SEB rechallenge. For this purpose, BALBk mice received two intraperitoneal injections of 100 pg SEB with a 48-h interval. First, we compared peak serum levels of IL-2, IFN-y and IL-10 after SEB rechallenge with those measured after a single SEB injection in control mice.The expected defect in IL-2 production in SEB-pretreated mice was associated with a major increase in IL-10 and IFN-y levels which were about fivefold higher than in controls. Experiments in mice depleted of CD4+ or CD8+ cells as well as studies in which purified T cell populations were rechallenged with SEB in vitro indicated that both CD4+ and CD8+ cells from SEB-pretreated mice were primed for IL-10 and IFN-y production. Furthermore, SEB-pretreated mice were sensitized to the toxic effects of the superantigen as indicated by a 30-70% lethality rate (vs. 0% in naive mice) within 48 h after SEB rechallenge. IFN-y was involved in the lethal syndrome as it could be prevented by injection of neutralizing anti-IFN-y monoclonal antibody. We conclude that SEB-reactive T cells made deficient for the production of IL-2 by exposure to SEB in vivo are primed for IFN-y and IL-10 production, and that IFNy up-regulation is involved in the shock syndrome occurring upon SEB rechallenge.