Human uterine epithelial RL95-2 and HEC-1A cell-line adhesiveness: the role of plexin B1

Objective: To study the expression of plexin-B1 in high- and low-receptive epithelial-endometrial cell lines, and 1 its possible role in endometrial adhesiveness. Design: Controlled, laboratory study. Setting: Laboratory for Research in Reproductive Sciences, Department of Obstetrics and Gynecology, Ha'Emek Medical Center, Afula, Israel. Patient(s): None. Intervention(s): None. Main Outcome Measure(s): This study was designed to explore and compare the expression and role of plexin-B1 in endometrial cell lines RL95-2 and HEC-1A, used as models of receptive and nonreceptive cells, respectively. The expression of plexin-B1 was analyzed by Western blotting and reverse-transcriptase polymerase chain reaction. The possible role of plexin-B1 in endometrial-trophoblast adhesiveness was studied with attachment and invasion assays. For further validation, we transfected HEC-1A cells with an expressing vector encoded for plexin-B1. Result(s): Significant differences in spheroid attachment was observed between RL95-2 and HEC-1A cells. Western blotting and reverse-transcriptase polymerase chain reaction revealed that in RL95-2 cells, the expression of plexin-B1 was significantly higher. An attachment assay that used RL95-2 cells in the presence of 1 inhibiting antibodies against plexim-B1 significantly decreased the attachment rates of spheroids. A comparison between HEC-1A and transfected HEC-1A (HEC-1A-2) cells showed significant differences in spheroid attachment. No significant difference was found between HEC-1A-2 and RL95-2. An attachment assay using inhibitory antibodies against plexin-B1 significantly decreased the spheroid-attachment rate. Conclusion(S): Based on our results, we think that plexin-B1 contributes to trophoblast-endometrium interactions, most likely by enhancing adhesion properties.