Fig. 1. Expressions of RANK/RANKL at the maternal-fetal interface.

a Immunohistochemistry analysis of RANKL and RANK expression in decidua from normal pregnancy (n = 10), control endometrium from non-pregnant women (NP, n = 10), and decidua from women with recurrent spontaneous abortion (RSA) (n = 8). Original magnification: ×200. b, c Flow cytometry (FCM) analysis of membrane RANKL expression on decidual stromal cells (DSCs) from women with NP decidua (n = 6) and RSA decidua (n = 6). d, e FCM analysis of RANK expression on γδ T cells in peripheral blood (n = 7), NP decidua (n = 7), and RSA decidua (n = 7). Data are shown as the mean ± SD. *P < 0.05, ***P < 0.001, and ****P < 0.0001 (Student’s t-test or Kruskal–Wallis H test). NC normal control, PBMC peripheral blood mononuclear cells, DIC decidual immune cell, pγδ T γδ T cells from peripheral blood, dγδ T γδ T cells from decidua