Interleukin-8 differentially modulates interleukin-4- and interleukin-2-induced human B cell growth.
The effect of interleukin-8 (IL)-8 on human B cell growth, as determined by thymidine uptake and viable cell numbers was studied. IL-8 inhibited IL-4-induced growth of B cells costimulated with anti-mu antibodies (Ab) or Staphylococcus aureus Cowan strain I (SAC) in a dose-dependent fashion. In contrast, IL-8 did not inhibit IL-2-induced growth of B cells. The IL-8-mediated inhibition was specific, since it was blocked by anti-IL-8 mAb but not by control IgG1. Moreover, anti-tumor necrosis factor-alpha (anti-TNF-alpha) Ab blocked IL-8-mediated inhibition. On the other hand, TNF-alpha, but not other cytokines including IL-1 beta, IL-3, IL-5, IL-6, interferon-alpha (IFN-alpha) or IFN-gamma, inhibited IL-4-mediated growth, and inhibition by TNF-alpha was blocked by anti-TNF-alpha Ab but not by control IgG. IL-4 had no effect on TNF-alpha binding by B cells while it decreased TNF-alpha production by B cells. IL-8 had no effect in binding of IL-4, IL-2 or TNF-alpha by B cells, however, it enhanced TNF-alpha production by B cells. These results indicate that IL-8 inhibited IL-4-induced human B cell growth by enhancement of endogenous TNF-alpha production.
Kimata
H
H
Department of Pediatrics, Kyoto University Hospital, Japan.
Lindley
I
I
D001402:B-Lymphocytes / Q000166:cytology / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000494:pharmacology*; D015847:Interleukin-4 / Q000494:pharmacology*; D016209:Interleukin-8 / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology
D007376:Interleukin-2; D016209:Interleukin-8; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4