Deregulated c-fos modulates IgG2b production of B cells mediated by lipopolysaccharide

M Takada1, T Koizumi, D Bachiller

  • 1Department of Immunology, ICMR, Kobe University School of Medicine, Japan.

Immunobiology
|July 1, 1993
PubMed

We have examined effects of the deregulated c-fos protein on IgG2b production of B cells cultured with lipopolysaccharide (LPS) using splenic B cells from a transgenic line carrying the mouse c-fos gene under the control of the interferon alpha/beta (IFN) inducible Mx promoter (Mx-c-fosD). High c-fos expression was induced in the Mx-c-fosD B cells during the first two days of culture. DNA synthesis and IgG2b production were augmented in the culture. When IFN was added together with LPS, the high c-fos expression was prolonged until day 3 of culture. IgG2b production was remarkably suppressed. However, the production was not suppressed by upregulation of c-fos via exogenous IFN on day 4 of culture. These results suggest a regulatory effect of the c-fos protein on the differentiation of B cells to IgG2b producing cells at a distinct period.

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