Identification of PDGF receptors on human megakaryocytes and megakaryocytic cell lines.

The Centre for Thrombosis and Vascular Research, School of Pathology, The University of New South Wales and Department of Haematology, The Prince of Wales Hospital, Sydney, Australia.
Thrombosis and Haemostasis (Impact Factor: 5.76). 09/1997; 78(2):892-6.
Source: PubMed

ABSTRACT Platelet-derived growth factor (PDGF) is a potent chemotactic and mitogenic factor implicated to play important roles in a variety of normal and pathophysiologic settings. We investigated PDGF receptor expression on human megakaryocytes and several megakaryocytic cell lines (CHRF, DAMI, Meg-01, M-07e) using enzyme-linked immunosorbent assay (ELISA), flow cytometry and immunocytochemical staining. Both PDGF receptor subtypes were identified on CHRF, DAMI, and Meg-01 cells by ELISA; PDGF beta-receptor levels exceeded alpha-receptor levels. Flow cytometry revealed that beta-receptor levels on CHRF and DAMI cells exceeded those on Meg-01 cells, and that M-07e expressed neither receptor. Immunocytochemical staining confirmed these findings and determined that bone marrow megakaryocytes also expressed PDGF receptors. Exposure of megakaryocytes to PDGF-BB dramatically induced the expression of the immediate-early gene, c-fos, within 30 min. Moreover, PDGF-BB significantly stimulated CHRF proliferation and colony formation. The present study demonstrates the presence of functional PDGF receptors on human megakaryocytes and their ability to mediate a mitogenic response.

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