IMMUNOCHEMICAL DETECTION OF CD14 ON HUMAN GINGIVAL FIBROBLASTS IN-VITRO

The activation of monocytes and macrophages induced by lipopolysacchar ide has been shown to contribute to the binding of lipopolysaccharide and lipopolysaccharide-binding protein complex to the cell surface CD1 4 molecule, To clarify the mechanism of the lipopolysaccharide-induced modulation of the function of gingival fibroblasts, ive investigated the effect of anti-CD 14 on interleukin 6 (IL-6) production on human g ingival fibroblasts in vitro. Immunochemical staining revealed weak po sitivity for CD14 on fibroblasts from healthy gingiva, while strong po sitivity for CD14 was found on fibroblasts From inflamed gingiva. West ern blot profiles of the fibroblasts and monocytes showed a CD14-posit ive reaction at 55 kDa, Fluorescein isothiocyanate-conjugated Escheric hia coli lipopolysaccharide bound to fibroblasts more strongly in the presence of 10% fetal bovine serum than without serum. This binding, a s well as IL-6 production, was blocked by anti-CD14, monoclonal antibo dy. The results showed that CD14 was present on human gingival fibrobl asts, which suggests that lipopolysaccharide modulation of gingival fi broblast Function depends on CD14.