Markers for human placental trophoblasts in two-dimensional gel electrophoresis.

Primary cultures of trophoblasts established from human term placentae showed high viability and reproducibility. Two-dimensional gel patterns obtained by metabolically labeling the trophoblasts with [35S]-methionine demonstrated that their pattern of gene expression was stable during the 6-d period investigated. Gel analysis demonstrated the keratins 7, 8, 14, 17, 18, and 19. Analysis of the gel pattern confirmed the presence of a small proportion of contaminating fibroblasts and lymphocytes. The gel patterns were compared with that of skin fibroblasts, peripheral lymphocytes, and epithelial cells to identify a group of proteins that are enriched in the trophoblasts and thus may be used as marker for these cells.