A motif in PSG11s mediates binding to a receptor on the surface of the promonocyte cell line THP-1
Year: 1995
Type: article
Abstract: The pregnancy-specific glycoproteins (PSG) form a large family of essential pregnancy proteins, but their biological function is unknown. We have investigated whether one function of the PSG is to interact with cells of the maternal immune system. Normal human peripheral blood mononuclear cells, activated with phorbol ester, are shown to bind to purified placental PSG. This binding activity can be mimicked using a chemically synthesized peptide ligand containing the Arg-Gly-Asp (RGD) motif present in the N-terminal domain of PSG11s. The PSG11s receptors are present on cells of the myeloid cell lineage but not of the T cell or B cell lineages. The binding is mediated in part by the RGD motif and can be competed against by appropriate RGD-containing, but not Arg-Ala-Asp (RAD)-containing, ligands. Ligand binding requires a functional cytoskeleton. By examining the U937 and THP-1 promonocyte cell lines, the presence of receptors with two different binding characteristics are demonstrated. The THP-1 receptor is identified by chemical cross-linking as a protein of 46 kilodaltons (kDa), and affinity chromatography demonstrates the presence of three protein species of 32 kDa, 16.8 kDa, and 15.9 kDa, suggesting the receptor has multiple subunits.
Source: Molecular Endocrinology
DOI: 10.1210/me.9.10.1297
Authors: K J Rutherfurd, J Y Chou, B C Mansfield
Institution: Massey University
Language: English
Subfield: Immunology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W2031576496
