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Transforming growth factor beta modulates C3 and factor B biosynthesis and complement receptor 3 expression in cultured human monocytes.

A K Høgåsen·K Hestdal·K Høgåsen·T G Abrahamsen
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Abstract

Complement biosynthesis in monocytes is stimulated by different pathogens and modulated by a variety of cytokines, but little is known about the possible effect of transforming growth factor beta (TGF-beta) on this monocyte function. We therefore studied the effect of TGF-beta 1 and TGF-beta 2 on constitutive, lipopolysaccharide (LPS)- and Candida albicans-induced monocyte biosynthesis of complement components C3 and factor B. Under all three conditions, both forms of TGF-beta (20 ng/ml) induced a two- to fourfold increase in C3 concentration in monocyte supernatants harvested after 2 or 5 days of cell culture, an effect that was abrogated by cycloheximide. In contrast, constitutive and pathogen-induced production of factor B was suppressed by TGF-beta. The effects of TGF-beta on complement production were neutralized by a monoclonal anti-TGF-beta antibody. Moreover, TGF-beta suppressed the pathogen-induced release of granulocyte-macrophage colony-stimulating factor and down-regulated the expression of complement receptor 3 (CD11b/CD18), while the expression of CD11a/CD18, a related beta 2 integrin, was unaffected. These novel effects of TGF-beta emphasize the immunomodulatory significance of this cytokine.

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Adjuvants, ImmunologicAnimalsAntibodiesAntigens, SurfaceCandida albicansCells, CulturedComplement C3Complement Factor BCycloheximideGranulocyte-Macrophage Colony-Stimulating FactorHumansLipopolysaccharidesMonocytesPhenotypeReceptors, ComplementSecretory RateTransforming Growth Factor betaJournal ArticleResearch Support, Non-U.S. Gov't

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A K Høgåsen, K Hestdal, K Høgåsen, T G Abrahamsen. 1995. Transforming growth factor beta modulates C3 and factor B biosynthesis and complement receptor 3 expression in cultured human monocytes.. https://doi.org/10.1002/jlb.57.2.287

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