title: Trisomy 21 placentas: histopathological and immunohistochemical findings using proliferating cell nuclear antigen.
abstract: OBJECTIVE
  The cause of growth retardation in trisomy 21 and other autosomal trisomies is not known, but may be the result of defective cell proliferation, slowing of the cell cycle, or placental structural abnormalities. Abnormalities of the fetal cell cycle may be reflected in placental growth and can be detected using proliferating cell nuclear antigen (PCNA).
  
  
  METHODS
  Twelve second-trimester and six third-trimester trisomy 21 placentas were examined histopathologically and stained immunohistochemically using antibodies to PCNA. Normal age-matched placentas were used as controls.
  
  
  RESULTS
  The second-trimester trisomy 21 placentas all exhibited many large irregular hypovascular villi. The third-trimester trisomy 21 placentas showed two patterns: (i) many large, irregular hypovascular villi, and (ii) relatively normal-appearing villi with only a few abnormal villi and focal hypervascularity. PCNA staining was significantly greater in second-trimester placentas when compared to third-trimester placentas for both trisomy 21 and controls. There was no significant difference in PCNA staining in trisomy 21 placentas when compared to the normal age-matched controls.
  
  
  CONCLUSIONS
  PCNA staining indicates no significant differences in proliferation between normal and trisomy 21 placentas. Trisomy 21 placentas show villus abnormalities, including hypovascularity.
authors.affiliation: Department of Pathology, Hutzel Hospital, Wayne State University School of Medicine, Detroit, Mich., USA.
authors.forename: F
authors.initials: F
authors.lastname: Qureshi
authors.forename: S M
authors.initials: SM
authors.lastname: Jacques
authors.forename: M P
authors.initials: MP
authors.lastname: Johnson
authors.forename: R F
authors.initials: RF
authors.lastname: Hume
authors.forename: R L
authors.initials: RL
authors.lastname: Kramer
authors.forename: Y
authors.initials: Y
authors.lastname: Yaron
authors.forename: M I
authors.initials: MI
authors.lastname: Evans
mesh_terms: D002824:Chorionic Villi / Q000473:pathology; D004314:Down Syndrome / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007150:Immunohistochemistry; D009929:Organ Size; D010920:Placenta / Q000737:chemistry* / Q000473:pathology*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis*; D017154:Stromal Cells / Q000473:pathology
chemical_list: D018809:Proliferating Cell Nuclear Antigen