Characteristics of Trophoblasts in Long-Term Culture.

We analyzed more than 40 cytotrophoblast cultures derived from cell islets that grew from trypsinized tissue fragments of placental microvilli. Phenotypic variability of trophoblasts was demonstrated. Changes in trophoblast morphology from epithelium-like or oval cells to bipolar and spindle-shaped or twisted and then to mesenchymal-like cells as well as intensive expression of cytokeratin-7 and vimentin attested to epithelial-mesenchymal transition of trophoblasts during in vitro culturing. Analysis of the expression of specific markers in long-term trophoblast culture (≥7 passages) revealed the possibility of culture contamination with other non-trophoblast cells including fibroblasts. High risk of trophoblast culture contamination with rapidly growing cells necessitates regular control of the cultures used in fundamental studies. Our experiments confirmed the possibility of long-term culturing of cells maintaining trophoblast properties. The identity and purity of 4 trophoblast cultures free from contamination and retaining the properties of pure culture during long-term (>10 passages) culturing in vitro were confirmed.

IFPA Meeting 2012 Workshop Report II: epigenetics and imprinting in the placenta, growth factors and villous trophoblast differentiation, role of the placenta in regulating fetal exposure to xenobiotics during pregnancy, infection and the placenta.

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2012 there were twelve themed workshops, four of which are summarized in this report. These workshops related to various aspects of placental biology: 1) epigenetics and imprinting in the placenta; 2) growth factors and villous trophoblast differentiation; 3) role of the placenta in regulating fetal exposure to xenobiotics during pregnancy; 4) infection and the placenta.