Differential expression of the common beta and specific alpha chains of the receptors for GM-CSF, IL-3, and IL-5 in endothelial cells

Abstract

The present study was designed to reexamine the interaction of granulocyte-macrophage colony-stimulating factor (GM-CSF) with endothelial cells (EC) and to investigate the expression of CSF receptor chains in these cells. In agreement with previous data, GM-CSF induced directional migration and, to a lesser degree, proliferation of human umbilical vein EC. When compared to basic fibroblast growth factor, GM-CSF was comparable in terms of chemotactic activity and was substantially less active in terms of proliferation. Binding studies confirmed the presence of receptors for GM-CSF (GM-CSFR) on EC. The expression of the beta chain common to the GM-CSFR, IL-3 receptor, and IL-5 receptor, as well as of the individual alpha chains, was studied by Northern analysis and/or reverse transcription and polymerase chain reaction. EC expressed high levels of the common beta chain transcripts. Expression of the alpha(GM) and alpha(IL-5) chain mRNA was minimal or absent in normal EC, though the transformed ECV304 endothelial cell line had substantial amounts of alpha(GM) chain mRNA. Unexpectedly, EC expressed alpha(IL-3) chain transcripts. IL-3 induced migration of EC across polycarbonate filters, whereas IL-5 was inactive.