Interferon-gamma inhibits the proliferation but not the differentiation of murine B cells in response to IL-5.
Interferon-gamma (IFN-gamma) is supposed to be produced by type 1 helper T cells (TH1) and inhibits IL-4-dependent B cell growth and differentiation. IL-5 (T cell-replacing factor, TRF), is a T cell-derived lymphokine which is predominantly produced by type 2 helper T cells (TH2) and regulates proliferation and differentiation of activated B cells. In this study, the effect of IFN-gamma on IL-5-dependent B cell growth and differentiation has been studied using murine chronic B cell leukemic cells (BCL1), normal splenic B cells, and cloned early B cell line. IFN-gamma selectively inhibits the IL-5-mediated proliferation of activated B cells as well as cloned early B cell lines at a low concentration (2 U/ml) in which polyclonal IgM production was not affected. This inhibitory effect of IFN-gamma occurs within 24 h after the onset of culture, as demonstrated by the inability of antibody to IFN-gamma to reverse totally the IFN-gamma-mediated suppressive effects if it was added later than 24 h after the onset of the culture. On the contrary, IL-5-mediated IgM secretion of BCL1 and IgA formation of LPS-stimulated normal B cells were relatively resistant to the suppressive effect of IFN-gamma. IFN-gamma does not affect the receptor expression for IL-5. Interestingly, IL-4-mediated IgG1 formation of LPS-stimulated B cells was markedly suppressed by IFN-gamma at 10 U/ml. These results strongly suggest that IFN-gamma may have differential effects on IL-5-mediated B cell triggering.
Hitoshi
Y
Y
Department of Biology, Kumamoto University Medical School, Japan.
Mita
S
S
Tominaga
A
A
Kikuchi
Y
Y
Sonoda
E
E
Takatsu
K
K
Watanabe
Y
Y
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D001665:Binding Sites; D002454:Cell Differentiation; D002460:Cell Line; D004247:DNA / Q000096:biosynthesis; D007136:Immunoglobulins / Q000378:metabolism; D007371:Interferon-gamma / Q000494:pharmacology*; D015848:Interleukin-5 / Q000378:metabolism / Q000494:pharmacology*; D007700:Kinetics; D008213:Lymphocyte Activation; D051379:Mice
D007136:Immunoglobulins; D015848:Interleukin-5; D007371:Interferon-gamma; D004247:DNA