Fig. 1

Continued cultures and expansion of mouse endometrial epithelial cells (MEECs). A A schematic diagram to illustrate the isolation, expansion, and ALI 3D cultures of MEECs. B The morphology of MEECs in CR condition (upper panel) and regular condition (lower panel). The fresh murine uterus tissues were minced into pieces and dispersed into single cells. And then cells were plated in primary epithelial culture basic medium (PECBM) and co-cultured with irradiated mouse fibroblasts as described in “Materials and methods” section or DMEM supplemented with 10% FBS. The morphology of MEECs was photographed under the phase contrast microscope. Magnification 10 ×. MEECs were marked as “epi.” C The growth curve of MEECs. The cell growth curve was plotted as accumulated population doublings versus time (days). D Cell identification (Cell ID)—the short tandem repeat (STR) analysis of the MEECs. STR analysis showed that 10 STR loci of MEECs do not match any other cell lines registered in the database