Low Expression Levels of CXCL12, CXCR4, and CXCR 7 in Peripheral Blood and Decidual Tissues are Associated with Miscarriage in Women

Miscarriage can cause significant physical and psychological harm to women. The stromal cell-derived factor 1 (SDF-1, also known as CXCL12)/C-X-C motif chemokine receptor 4 (CXCR4) and C-X-C motif chemokine receptor 7 (CXCR7) axis can promote the proliferation and invasion of trophoblast cells in early pregnancy, and maintain immune tolerance at the maternal-fetal interface to aid with pregnancy success. From our findings, the serum CXCL12 level of women who have miscarried (n = 25) was significantly lower than that of healthy early pregnancy women (n = 20) by ELISA (P < .001). Additionally, CXCL12 levels in normal non-pregnant women (n = 20) were significantly lower than those in early pregnancy women (P < .001) and women who have miscarried (P < .001). Quantitative real-time PCR detected no significant difference in the mRNA transcription levels of CXCR4 and CXCR7 in the decidua tissues of women with early pregnancy (n = 20) and miscarriage (n = 20) (P = .724, P = .281, respectively). However, Western blot and immunohistochemistry of CXCR4 and CXCR7 in decidual tissue of women who have miscarried (n = 20) were significantly lower than those in early pregnancy women (n = 20) (P < .05 for both). Therefore, we believe that the increased serum CXCL12 levels in pregnant offspring may benefit normal pregnancy maintenance. The low level of CXCL12 in peripheral blood and the low expression of CXCR4 and CXCR7 proteins in decidua may be associated with the occurrence of early spontaneous abortion, and the clinical application value of serum CXCL12 in predicting adverse pregnancy outcomes is worth further exploring.