title: Co-localization of beta 2-microglobulin and IgG in human placental syncytiotrophoblasts.
abstract: The fetal syncytiotrophoblast cells in close contact with maternal blood circulation apparently lack surface expression of HLA molecules, including the HLA light chain beta 2-microglobulin. This is thought to contribute significantly to a successful pregnancy. We find that syncytiotrophoblasts do express beta 2-microglobulin. Beta 2-microglobulin is primarily localized intracellularly in apical granules, and co-localize with human IgG. The origin and function of syncytiotrophoblast beta 2-microglobulin is unknown, but its localization in the syncytiotrophoblasts may implicate beta 2-microglobulin in the transplacental transport of IgG in conjunction with a recently identified class I HLA-like receptor for IgG/Fc. Alternatively, beta 2-microglobulin may associate with a hitherto unidentified class I HLA molecule.
authors.affiliation: Department of Microbiology and Immunology, The Gade Institute, University of Bergen, Norway.
authors.forename: E K
authors.initials: EK
authors.lastname: Kristoffersen
authors.forename: R
authors.initials: R
authors.lastname: Matre
mesh_terms: D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000737:chemistry*; D007150:Immunohistochemistry; D018613:Microscopy, Confocal; D011247:Pregnancy; D014327:Trophoblasts / Q000737:chemistry / Q000276:immunology*; D001613:beta 2-Microglobulin / Q000737:chemistry*
chemical_list: D007074:Immunoglobulin G; D001613:beta 2-Microglobulin