Figure 1

Expression of β1 integrin by trophoblasts cultured with uterine endothelial cells. Trophoblasts were added to confluent cultures of endothelial cells and cocultured for 24 h as described in Methods. The cultures were fixed in methanol and stained using antibodies against β1 integrin or cytokeratin. (A) Trophoblasts cultured alone and stained for β1 integrin. (B) Trophoblasts cultured on top of endothelial cells for 24 h then stained for β1 integrin. (C) Trophoblasts cultured on top of endothelial cells then fixed in methanol and stained for β1 integrin. (D) Same field as in C but viewed to show cytokeratin (red) staining. (E) Trophoblasts cultured alone in endothelial cell-conditioned medium then stained for β1 integrin. (F) Control culture incubated with isotype-matched mouse immunoglobulin. (G) Trophoblasts cocultured with REN cells and stained for β1 integrin. (H) Same field as G but viewed to show cytokeratin staining. These experiments were performed four times and representative images are shown. The horizontal bar represents 20 μm.