Effect of the different dimeric forms of the platelet‐derived growth factor on cellular responses in mouse Swiss 3T3 fibroblasts

Abstract

PDGF consists of two polypeptide chains, A and B, and all three possible dimers have been isolated from different sources. Human PDGF, essentially AB, porcine PDGF (BB) and recombinant PDGF-AA were tested on Swiss 3T3 fibroblasts for their ability to stimulate mitogenesis, phosphoinositide turnover and tyrosine phosphorylation of the PDGF receptor. When used in saturating amounts, the three isoforms were equally active in inducing mitogenesis. However, PDGF-AA was less active than AB and BB to induce the phosphorylation of the receptor and the turnover of phosphoinositides (30~ and 50%, respectively). These findings suggest that, in Swiss 3T3 fibroblasts, PDGF receptors of the a-type are present in a slightly lower amount than//-type. In addition, the two types of receptor appear to have similar physiological functions.Platelet-derived growth factor isoform; Tyrosine phosphorylation; Platelet-derived growth factor receptor; Mitogenesis; Phosphoinositide; (Mouse fibroblast)

Upregulation of the PDGF-alpha Receptor Precedes Asbestos-induced Lung Fibrosis in Rats

“…PDGF-AA is not a strong stimulus for proliferation in primary RLFs because of the low expression of the PDGF-R␣, but PDGF-AA mitosis does increase substantially after asbestos-induced upregulation of the PDGF-R␣ expression in vitro (19). Swiss 3T3 cells have an equal number of PDGF-R␣ and PDGF-R␤ and have a mitogenic response to PDGF-AA, which is 70% of that induced by PDGF-BB (29).…”

Interstitial fibrosis and growth factors.

“…A series of studies in this field has demonstrated that PDGF is produced by these mesenchymal cell populations (21,(106)(107)(108)(109). Accordingly, there are a few reports suggesting that there may be a PDGF-dependent autocrine proliferative mechanism in lung fibroblasts.…”

Platelet-derived growth factor (PDGF)-AB-mediated phosphorylation of PDGF β receptors

“…Platelet-derived growth factor (PDGF) is a potent mitogen for cells of mesenchymal origin, and stimulates the proliferation of density-arrested Balb/c-3T3 fibroblasts (Pledger et al, 1978;Williams et al, 1982;Sturani et al, 1989;Coats et al, 1991). PDGF was first purified from human platelets and shown to consist of a heterodimer composed of two disulphide-linked polypeptide chains, designated A and B (PDGF-AB) (Antoniades et al, 1979;Heldin et al, 1979;Raines and Ross, 1982).…”