Production of C5a antagonist by synovial and peritoneal tissue fibroblasts

Abstract

Fibroblasts grown from synovial and peritoneal tissues release into the medium an inhibitor of neutrophil chemotaxis. The inhibitor resembles the antagonist previously described in synovial and peritoneal fluids. It is a heat stable (56 degrees C) protein of MW approximately 40 kDa that counteracts the chemotactic activity of zymosan-activated serum or purified C5a but not the peptide chemoattractant F-met-leu-phe. No chemotactic inhibitor was detected in media from skin fibroblast cultures or in formal human sera. It is suggested that the inhibitor is produced locally by synovial and peritoneal fibroblasts and that it might play a role in the regulation of inflammation at sites lined with mesothelium.

Cancers and the concept of cell senescence

“…Skin fibroblasts do not secrete the antagonist. This finding is consistent with the hypothesis that the fibroblasts of those cavities are regulators of inflammation at sites lined with an epithelium of mesodermal origin (Matzner et al 1986). Testosterone metabolism, the amount of androgen receptor, and the 5-alpha-reductase activity are higher in fibroblast cultures originated from genital skin than in those from other areas (Kaufman et al 1975;Lamberigts et al 1979;Griffin et al 1981).…”

“…Some of the distinctions between the fibroblasts from different tissues are probably necessary to provide for the metabolism of the respective organs and must play a role in the interaction with particular cell types. Peritoneal and synovial fibroblasts for instance, synthesize an antagonist of the C5a peptide, which is chemotactic for neutrophiles (Matzner et al 1986). Skin fibroblasts do not secrete the antagonist.…”