Fig. 1

CXCL12 and CXCR4 were both expressed in human first-trimester EECs in vivo. Expression of CXCL12 and CXCR4 proteins in human first-trimester endometrial epithelial cells (EECs) of decidual tissues was measured with immunohistochemical analysis. CXCL12 and CXCR4-specific brown-colored staining was clearly observed in the cytoplasma of EECs (n = 5). No specific staining was observed in the negative control. Human first-trimester villi were used as positive controls