Interleukin-6 gene expression and production induced in human monocytes by membrane proteoglycans from Klebsiella pneumoniae.

The present study was designed to investigate the effect of membrane proteoglycans (MPG) from Klebsiella pneumoniae on IL-6 production by human peripheral blood monocytes. Exposure in vitro to MPG induced release of IL-6 activity from human monocytes, as assessed by the 7TD1 hybridoma assay. MPG-induced hybridoma growth factor activity was blocked by anti-IL-6 antibodies. MPG induced expression in human monocytes of IL-6 mRNA transcripts as assessed by Northern blot analysis. Induction of IL-6 in mononuclear phagocytes may play a role in the immunomodulatory activity of MPG.