title: Milk fat globule epidermal growth factor 8 (MFG-E8): a novel protein in the mammalian endometrium with putative roles in implantation and placentation.
abstract: OBJECTIVE
  MFG-E8 is a novel endometrial protein with conserved functions in tissue remodeling and angiogenesis in non-uterine tissues. Our aims were: 1. To examine the presence of MFG-E8 protein in the human endometrium during the window of implantation, in human endometrial cell lines, in human placental tissue at different gestational ages, and in murine implantation sites during early gestation; and 2. To study the regulation of MFG-E8 mRNA expression in mice implantation sites.
  
  
  METHODS
  MFG-E8 protein and its receptor integrin αvβ3 were detected by immunostaining in human endometrial biopsies obtained from normal volunteers, in human endometrial cell lines (epithelial: Ishikawa and HEC-1A, stromal: HESC, and endothelial: HEEC), in human products of conception from all trimesters of gestation, and in murine implantation and inter-implantation sites dissected on days 5 and 8 post-coitus. MFG-E8 gene expression was assessed by RT-PCR.
  
  
  METHODS
  Immunohistochemical determination of MFG-E8 in endometrium and products of conception as well as relative MFG-E8 mRNA expression in mice implantation sites.
  
  
  RESULTS
  MFG-E8 protein was present almost exclusively in the epithelial compartment of human endometrium. It was also expressed in the cytotrophoblasts and syncytiotrophoblasts outlining chorionic villi of the human placenta at all trimesters of gestation, and in murine implantation sites. MFG-E8 mRNA was significantly up-regulated in murine implantation sites and with increased gestational age.
  
  
  CONCLUSIONS
  MFG-E8 expression in the endometrial epithelium as well as in chorionic villi suggests its possible role in endometrial reorganization during the receptive phase and in events related to normal pregnancy in mammals.
authors: The Jones Institute for Reproductive Medicine, Department of Obstetrics and Gynecology, Eastern Virginia Medical School, 601 Colley Ave., Norfolk, VA 23507-1627, USA. boccas@evms.edu
authors: S M
authors: SM
authors: Bocca
authors: S
authors: S
authors: Anderson
authors: B
authors: B
authors: Amaker
authors: R J
authors: RJ
authors: Swanson
authors: A
authors: A
authors: Franchi
authors: F
authors: F
authors: Lattanzio
authors: S
authors: S
authors: Oehninger
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000502:physiology*; D002460:Cell Line; D010064:Embryo Implantation / Q000502:physiology*; D004717:Endometrium / Q000378:metabolism*; D004815:Epidermal Growth Factor / Q000235:genetics / Q000502:physiology*; D005260:Female; D006801:Humans; D039302:Integrin alphaVbeta3 / Q000096:biosynthesis; D008597:Menstrual Cycle; D051379:Mice; D008894:Milk Proteins; D010929:Placentation / Q000502:physiology*; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D000954:Antigens, Surface; D039302:Integrin alphaVbeta3; C098942:MFGE8 protein, human; C490919:Mfge8 protein, mouse; D008894:Milk Proteins; D012333:RNA, Messenger; D004815:Epidermal Growth Factor