title: Detection of zona pellucida proteins during human folliculogenesis.
abstract: BACKGROUND
  The stage of folliculogenesis at which the human zona pellucida (ZP) is initiated and the cells responsible for the origin of the ZP continue to be controversial. This study characterizes the development of the ZP during human folliculogenesis using ovarian samples donated from patients requesting ovarian storage.
  
  
  METHODS
  Follicles (from n = 18 patients, 14-40 years old) within fresh tissue and following development in a xenograft system were stained, using immunohistochemical techniques, for the presence of the three human ZP proteins, ZP1, ZP2 and ZP3. Over 500 primordial follicles and >20 follicles at each developmental stage were examined.
  
  
  RESULTS
  All three ZP proteins were detected within the oocyte of the primordial follicle. Presence of ZP1 and ZP3 was observed in the majority of primordial oocytes (93% and 95%, respectively), whereas ZP2 was detected in only 32% of these follicles. The three ZP proteins were detected in the cytoplasm of cuboidal granulosa cells and their distribution correlates with developmental stages throughout folliculogenesis.
  
  
  CONCLUSIONS
  ZP proteins were detected in both the oocyte and the granulosa cells as early as the primordial follicle stage in the human. The detection of ZP proteins in the quiescent primordial follicle suggests that these proteins have been present since oogenesis.
authors.affiliation: Reproductive Services, Royal Women's Hospital, 132 Grattan Street, Carlton, Victoria 3053, Australia. debra.gook@rwh.org.au
authors.forename: Debra A
authors.initials: DA
authors.lastname: Gook
authors.forename: D H
authors.initials: DH
authors.lastname: Edgar
authors.forename: J
authors.initials: J
authors.lastname: Borg
authors.forename: M
authors.initials: M
authors.lastname: Martic
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D048430:Cell Shape; D015925:Cryopreservation; D003593:Cytoplasm / Q000378:metabolism; D004527:Egg Proteins / Q000378:metabolism*; D005260:Female; D006107:Granulosa Cells / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D009865:Oocytes / Q000378:metabolism; D006080:Ovarian Follicle / Q000502:physiology*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D013194:Staining and Labeling; D014018:Tissue Distribution; D014183:Transplantation, Heterologous; D000072216:Zona Pellucida Glycoproteins
chemical_list: D004527:Egg Proteins; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; C000606514:ZP1 protein, human; C000606515:ZP2 protein, human; C000606517:ZP3 protein, human; D000072216:Zona Pellucida Glycoproteins; C000606519:Zp1 protein, mouse; C000606520:Zp2 protein, mouse; C000606521:Zp3 protein, mouse