Interleukin-12 stimulates B cell growth by inducing IFN-gamma.
Human interleukin-12 (IL-12) is a 70-kDa polypeptide that activates human natural killer cells. It has been purified from the culture supernatant of a human Epstein-Barr virus-transformed B cell line and cloned. We show that native as well as recombinant IL-12 promoted growth of Staphylococcus aureus Cowan I strain (SAC) or anti-mu antibody-activated B cells in a dose-dependent manner. IL-12 also acted in synergy with IL-2 in growth and differentiation of SAC-activated B cells. Since anti-interferon (IFN)-gamma antibody completely abrogates B-cell growth factor (BCGF) activity of IL-12, the BCGF activity is mediated by IFN-gamma. This conclusion is clearly supported by the results that IL-12 indeed induced IFN-gamma production by activated B cells. These results suggest that the B cell proliferative effect of IL-12 may be mediated by autocrine IFN-gamma.
Li
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Laboratory of Cellular Immunology, Alton Ochsner Medical Foundation, New Orleans, LA 70121, USA.
Young
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D
Wolf
S F
SF
Choi
Y S
YS
D018951:Antigens, CD20 / Q000096:biosynthesis / Q000235:genetics; D001402:B-Lymphocytes / Q000166:cytology / Q000187:drug effects*; D001483:Base Sequence; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004357:Drug Synergism; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D018664:Interleukin-12 / Q000494:pharmacology*; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D014066:Palatine Tonsil / Q000166:cytology; D012333:RNA, Messenger / Q000032:analysis; D011994:Recombinant Proteins / Q000494:pharmacology; D013268:Stimulation, Chemical
D018951:Antigens, CD20; D007376:Interleukin-2; D012333:RNA, Messenger; D011994:Recombinant Proteins; D018664:Interleukin-12; D015847:Interleukin-4; D007371:Interferon-gamma