Objective: To study the expression of Toll-like receptor 2 (TLR2) and TLR4 in decidual tissue of patients with Unexplained Recurrent Spontaneous Abortion (URSA).
Methods: The decidual tissue of URSA patients (URSA group) and normal pregnancy abortion patients (control group) were collected. The expression of TLR2 and TLR4 protein was detected by immunohistochemical method. The expression of TLR2 and TLR4 mRNA in the decidua was detected by RT-PCR. The levels of Th1 cytokine (TNF-α and IFN-γ) and Th2 cytokine (IL-4) in peripheral blood were detected by ELISA.
Results: Compared with the control group, the levels of protein and mRNA of TLR2 and TLR4 in the deciduas of URSA group were significantly higher than those in the control group (P<0.05). The expression level of TNF-α and IFN-γ in URSA group was significantly higher (P<0.05). There was no significant difference in IL-4 between the two groups (P>0.05).
Conclusion: Compared with normal pregnant women, the expression of TLRs in URSA group was significant. The TLR2 and TLR4 release excess Th1 cytokines, leading to Th1/Th2 imbalance and URSA.