title: [Development and validation of an in vitro culture model for the study of the differentiation of human trophoblast].
abstract: OBJECTIVE
  To develop a method to isolate cells of human citotrophoblast and to assess its invading and differentiation capacity.
  
  
  METHODS
  Experimental biomedical.
  
  
  METHODS
  Citotrophoblasts of healthy placentas of full-term pregnancies were isolated by digestion with dispase and purification in a density gradient. The purity by immunoreactivity to citokeratin 7 and the invasiveness of the cells of citotrophoblast in Matrigel were evaluated. The enzymatic activity was determined through zimography and hCG secreted was quantified by means of ELISA. The expression of alpha 1 and alpha 5 integrins was evaluated by immunohistochemistry.
  
  
  RESULTS
  Citotrophoblasts with a purity of 97% were obtained; they differentiated themselves, in a spontaneous way, to a syncytium after four days. There was a growing production of hCG. Maximum invasiveness of citotrophoblasts ocurred the first two days, when their phenotype was mononuclear and coincided with the secretion of pro-MMP-9, and then it diminished according with the culture time. Immunoreactivity to the alpha 1 and alpha 5 integrins was observed in citotrophoblast cells with mononuclear phenotype. This immunoreactivity was lower in cells with phenotype of syncytium.
  
  
  CONCLUSIONS
  It was created an in vitro model that replicates events of the early development of the placenta. These events resemble the invasion and differentiation phase of the citotrophoblast. This model has potential utility in the study of the mechanisms of damage in preeclampsia.
authors.affiliation: Instituto Nacional de Perinatología Isidro Espinosa de los Reyes, colonia Lomas de Virreyes, CP, México, DF.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Martínez Flores
authors.forename: Jorge
authors.initials: J
authors.lastname: Beltrán Montoya
authors.forename: Alicia
authors.initials: A
authors.lastname: Ortega Aguilar
authors.forename: Felipe
authors.initials: F
authors.lastname: Vadillo Ortega
mesh_terms: D015415:Biomarkers; D002454:Cell Differentiation; D002465:Cell Movement; D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured / Q000166:cytology / Q000378:metabolism; D006063:Chorionic Gonadotropin / Q000378:metabolism; D003094:Collagen; D003470:Culture Media; D004338:Drug Combinations; D004792:Enzyme Precursors / Q000096:biosynthesis; D005260:Female; D015726:Giant Cells / Q000166:cytology; D006801:Humans; D066298:In Vitro Techniques; D007797:Laminin; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis / Q000378:metabolism; D008954:Models, Biological; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D011509:Proteoglycans; D014327:Trophoblasts / Q000166:cytology* / Q000378:metabolism
chemical_list: D015415:Biomarkers; D006063:Chorionic Gonadotropin; D003470:Culture Media; D004338:Drug Combinations; D004792:Enzyme Precursors; D007797:Laminin; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen; C120487:pro-matrix metalloproteinase 9; D020780:Matrix Metalloproteinase 9