Lymphocyte Immunotherapy Changed the Th1/Th2 and Th17/Treg Balance in Patients with Unexplained Recurrent Spontaneous Abortion

Abstract

Background: Lymphocyte immunotherapy (LIT) is regarded as an efficacious treatment for unexplained recurrent spontaneous abortion (URSA), but its mechanism remains controversial. T cells play an important role in maternal-fetal immune regulation. Therefore, in this study we aimed to investigate the proportions of T helper (Th)1, Th2, Th17, and Treg cells, as well as the change in the Th1/Th2 and Th17/Treg balance in peripheral blood mononuclear cells (PBMCs) in patients with unexplained recurrent spontaneous abortion treated with lymphocyte immunotherapy and who had subsequent successful pregnancies. Methods: Flow cytometry was used to characterize the population and proportion of Th1/Th2 and Th17/Treg balance in 38 patients before and after immunotherapy. Results: The percentage of Th1 cells increased significantly after immunotherapy in patients with URSA (14.96 ± 6.57%), when compared to pretreatment (12.98 ± 7.13%) (p < 0.01), and patients with URSA and LIT and having successful pregnancies (before: 13 ± 7.52%, after: 15.25 ± 6.89%; p < 0.01), while the Th1/Th2 balance decreased significantly (8.37 ± 4.14), when compared to pretreatment (14.08 ± 12.04) (p < 0.05). Furthermore, the proportion of Th1 and Th2 cells was significantly higher in the successful pregnant group, whereas the Th17/Treg balance in patients with URSA did not exhibit significant changes between before LIT (0.39 ± 0.25) and after LIT (0.33 ± 0.23), but decreased significantly in successful pregnancy after LIT (0.29 ± 0.17), when compared to before LIT (0.38 ± 0.25). Conclusions: LIT may alter the Th1/Th2 and the Th17/Treg balance, ensuring successful pregnancy.