title: Microvesicle-mediated release of soluble LH/hCG receptor (LHCGR) from transfected cells and placenta explants.
abstract: Placental hCG and pitutary LH transduce signals in target tissues through a common receptor (LHCGR). We demonstrate that recombinant LHCGR proteins which include the hormone-binding domain are secreted from transfected cells and that natural LHCGR is also secreted from human placental explants. LHCGR recombinant proteins representing varying lengths of the N-terminal extracellular domain were expressed in Chinese Hamster Ovary cells in suspension culture. Secretion was minimal up to 72h but by 96h 24-37% of the LHCGR had been released into the culture medium. The secreted proteins were folded and sensitive to glycosidases suggesting N-linked glycosylation. Secretion was independent of recombinant size and was mediated via structurally defined membrane vesicles (50-150nm). Similarly cultured human early pregnancy placental explants also released LHCGR via microvesicles. These studies provide the first experimental evidence of the possible mechanistic basis of the secretion of LHCGR.
authors.affiliation: Department of Clinical Biochemistry, Laboratory Medicine, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK.
authors.forename: Anne E
authors.initials: AE
authors.lastname: Chambers
authors.forename: Paul F
authors.initials: PF
authors.lastname: Stanley
authors.forename: Harpal
authors.initials: H
authors.lastname: Randeva
authors.forename: Subhasis
authors.initials: S
authors.lastname: Banerjee
mesh_terms: D000818:Animals; D016466:CHO Cells; D002478:Cells, Cultured; D006224:Cricetinae; D003412:Cricetulus; D005260:Female; D006801:Humans; D009924:Organ Culture Techniques; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011974:Receptors, LH / Q000235:genetics / Q000378:metabolism*; D022142:Secretory Vesicles / Q000378:metabolism*; D012995:Solubility; D014162:Transfection
chemical_list: D011974:Receptors, LH