CXCL12 controls over-invasion of trophoblasts via upregulating CD82 expression in DSCs at maternal-fetal interface of human early pregnancy in a paracrine manner.

Tetraspanin CD82 has been identified as a potential contributor to controlling trophoblast invasiveness in human first-trimester pregnancy. However, it is unclear how the regulation of CD82 expression at maternal-fetal interface. The present study is to investigate the effect of the trophoblast-derived CXCL12 on CD82 expression in decidual stromal cells (DSCs) that in turn controls trophoblast cell invasiveness. In-cell Western was used to evaluate the expression of CD82 in DSCs. A co-culture model was established to investigate the reciprocal interaction between trophoblasts and DSCs via CXCL12/CXCR4 and CD82 expression. We found that both anti-CXCL12 and anti-CXCR4 neutralizing antibody can eliminate increase of CD82 expression in DSCs induced by the trophoblasts supernatant. Moreover, the invasiveness of trophoblasts pre-treated with anti-CXCR4 neutralizing antibody was significantly decreased. Interestingly, when DSCs were pre-treated with anti-CXCR4 neutralizing antibody, the trophoblasts invasiveness in the co-culture was enhanced, and thus anti-CXCR4 neutralizing antibody can reverse the decrease of trophoblasts invasiveness induced by CD82. The trophoblast cell-derived CXCL12 does not only increase the invasiveness in an autocrine manner, but also control the over-invasion of trophoblasts through promoting CD82 expression in DSCs in a paracrine manner, which maintains a physiological balance of human trophoblasts invasiveness via the cross-talk between trophoblasts and DSCs.