This study is to investigate the mechanism of unexplained recurrent spontaneous abortion (URSA). A total of 35 cases of URSA patients (URSA group), 20 cases with normal pregnancy (normal pregnancy group) and 20 healthy non-pregnancy candidates (healthy control group) were enrolled in this study. Enzyme linked immunosorbent assay (ELISA) method was used for detection of serum soluble Tim-3 (sTim3) and Galectin-9. Cytokine bead array (CBA) determination method was used to detect IFN-γ and IL-4 expression levels. Compared with the healthy control group, sTim-3 levels in normal pregnancy group and URSA group increased, and URSA group had significantly higher sTim-3 levels than normal pregnancy group (P < 0.05). Compared with the healthy control group, Galectin-9 levels in normal pregnancy group and URSA group also increased. However, the normal pregnancy group had significantly higher Galectin-9 level than URSA group (P < 0.05). IFN-γ levels in normal pregnancy group and URSA group were lower than those in healthy control group, and IFN-γ levels in the normal pregnancy group were significantly lower than those in URSA group (P < 0.05). Levels of IL-4 in normal pregnancy group and URSA groups increased compared with the healthy control group, and the IL-4 levels in normal pregnancy group were significantly higher than those in URSA group (P < 0.05). Th1/Th2 imbalance, sTim-3 and Galectin-9 expression increase are found in the patients with URSA, ant this might be involved in the regulation of immunity in pregnancy.
Keywords: IFN-γ; IL-4; galectin-9; sTim-3; unexplained recurrent spontaneous abortion.