Instituto di Richerche Farmacologische Mario Negri , Consorzio Mario Negri Sud , Santa Maria Imbarao Chieti , Italy .
Exp Cell Res 193 : 208-12 ( 1991)
Abstract
Interleukin 1 beta ( IL-1 beta ) and platelet-derived growth factor ( PDGF ) induced proliferation in many cell types .
Both peptides are released by activated macrophages and other cells in response to injury and are thought to play a crucial role in a number of pathological processes .
We found that IL-1 beta stimulates proliferation of rabbit articular chondrocytes and induces synthesis and release of PDGF into their culture medium .
This effect , which is time- and dose-dependent ( 0.05-5 ng/ml ) , is restricted to PDGF-AA , one of the three PDGF isoforms ; IL-1 beta effect on PDGF is inhibited by actinomycin D and alpha-amanitin , suggesting a transcriptional regulation of PDGF-A chain .
IL-1 beta stimulates PDGF-AA synthesis also in the presence of indomethacin , a prostaglandin synthesis inhibitor .
Transforming growth factor beta 1 ( TGF-beta 1 ) , a dimeric polypeptide which displays multiple biological activities , inhibits in a dose-dependent manner ( 1-10 ng/ml ) PDGF-AA production induced by IL-1 beta .
In a binding assay , TGF-beta 1 induces 45% decrease in specific binding sites for I-IL-1 beta , with no change in affinity .