title: Distinct patterns of C4d immunoreactivity in placentas with villitis of unknown etiology, cytomegaloviral placentitis, and infarct.
abstract: C4d deposition is considered to be evidence of antibody-mediated rejection. This study was conducted to compare C4d immunoreactivity between villitis of unknown etiology (VUE) and cytomegaloviral placentitis. C4d immunohistochemistry was performed in cases with VUE (n = 16) and cytomegaloviral placentitis (n = 5). Distinct, linear C4d immunoreactivity along the syncytiotrophoblast was found in all VUE cases. In cytomegaloviral placentitis, the intensity of C4d immunoreactivity along the syncytiotrophoblast was not prominent, but cytoplasmic C4d immunoreactivity of villous cytotrophoblasts was frequently observed. Further screening of the cases with placental infarcts (n = 5) demonstrated prominent C4d immunoreactivity in the chorionic villi adjacent to the infarct. We report the characteristic co-localization of VUE and C4d immunoreactivity. The overall findings in this study strongly suggest that the complement activation is a common mechanism of diverse placental injuries associated with rejection, infection, and ischemia.
authors.affiliation: Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea.
authors.forename: K
authors.initials: K
authors.lastname: A Lee
authors.forename: Y W
authors.initials: YW
authors.lastname: Kim
authors.forename: J Y
authors.initials: JY
authors.lastname: Shim
authors.forename: H S
authors.initials: HS
authors.lastname: Won
authors.forename: P R
authors.initials: PR
authors.lastname: Lee
authors.forename: A
authors.initials: A
authors.lastname: Kim
authors.forename: C J
authors.initials: CJ
authors.lastname: Kim
mesh_terms: D000328:Adult; D002824:Chorionic Villi / Q000276:immunology; D003167:Complement Activation; D015935:Complement C4b / Q000032:analysis*; D003586:Cytomegalovirus Infections / Q000276:immunology*; D005260:Female; D006801:Humans; D007238:Infarction / Q000276:immunology; D007249:Inflammation / Q000276:immunology*; D010446:Peptide Fragments / Q000032:analysis*; D010920:Placenta / Q000098:blood supply / Q000276:immunology*; D010922:Placenta Diseases / Q000276:immunology* / Q000821:virology; D011247:Pregnancy; D014327:Trophoblasts / Q000276:immunology
chemical_list: D010446:Peptide Fragments; D015935:Complement C4b; C032261:complement C4d