EFFECTS OF BETA-1 INTEGRINS IN THE PROCESS OF IMPLANTATION

The expression and function of beta 1 integrins on human decidual cell s were investigated. mow cytometric analysis revealed that the culture d decidual. cells expressed a high level of the beta 1 subunit on the cell surface. Mouse blastocysts attached to and spread onto cultured h uman decidual cells. Attachment of the blastocysts was a necessary pre requisite for the further outgrowth of trophoblasts. The addition of a monoclonal antibody recognizing the beta 1 subunit to the cultured de cidual cells did not affect the rates of hatching and attachment of bl astocysts. The outgrowth of embryos on decidual cells was inhibited by the addition of the anti-beta 1-subunit antibody in a dose-dependent manner. Furthermore, exposure of decidual cells to the anti-beta 1-sub unit antibody signifcantly inhibited the extent of outgrowth of tropho blasts, implying that blastocyst attachment and outgrowth is mediated by different mechanisms. These observations suggest that beta 1 integr ins on decidual cells may be involved in the process of blastocyst dev elopment and differentiation after attachment.