title: Specific isoforms of leucine-rich alpha2-glycoprotein detected in the proliferative endometrium of women undergoing assisted reproduction are associated with spontaneous pregnancy.
abstract: OBJECTIVE
  To examine differences in specific protein expression from the surface of the human endometrium with respect to eventual pregnancy in infertile women.
  
  
  METHODS
  Laboratory study.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  Thirty-one women presenting for investigation into infertility at an assisted reproductive unit.
  
  
  METHODS
  Endometrial flushings were collected during the proliferative phase of the menstrual cycle and subjected to electrophoretic separation on the basis of isoelectric point and molecular weight. Computerized analysis of the resulting spots was performed, and the proteins were identified using tandem mass spectrometry.
  
  
  METHODS
  The expression of individual isoforms of leucine-rich alpha2-glycoprotein (LRG) was compared in nonpregnant patients (n = 25), those who became pregnant as a result of treatment (n = 3), and those who had treatment-independent pregnancies (n = 3).
  
  
  RESULTS
  A statistically significant difference was found in expression of two LRG isoforms, which were higher in the women who subsequently became pregnant independent of treatment.
  
  
  CONCLUSIONS
  Several indirect lines of evidence suggest a role for LRG in implantation/decidualization. [1] LRG is implicated in transforming growth factor beta signal transduction. [2] Similar sequences have been identified in murine uterine tissues. [3] LRG may be involved in the infiltration of decidua by uterine natural killer cells, given that the murine homolog of LRG supports lymphocyte infiltration into secondary lymphoid tissues. [4] Human uterine natural killer cells differentiate into granular forms during early pregnancy, and LRG is known to support neutrophil granulocytic differentiation in humans.
authors.affiliation: Academic Department of Obstetrics and Gynaecology, St. Bartholomew's School of Medicine and Dentistry, Queen Mary College University of London, London, United Kingdom. d.j.gillott@qmul.ac.uk
authors.forename: David J
authors.initials: DJ
authors.lastname: Gillott
authors.forename: Hazem M
authors.initials: HM
authors.lastname: Al-Rumaih
authors.forename: Kit-Yi
authors.initials: KY
authors.lastname: Leung
authors.forename: Abdallah
authors.initials: A
authors.lastname: Eldib
authors.forename: J Gedis
authors.initials: JG
authors.lastname: Grudzinskas
mesh_terms: D000328:Adult; D004717:Endometrium / Q000378:metabolism*; D005260:Female; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D007247:Infertility, Female / Q000378:metabolism* / Q000628:therapy*; D011247:Pregnancy / Q000378:metabolism*; D020033:Protein Isoforms / Q000378:metabolism; D027724:Reproductive Techniques, Assisted
chemical_list: D006023:Glycoproteins; C015246:LRG1 protein, human; D020033:Protein Isoforms