Diminished miR-374c-5p negatively regulates IL (interleukin)-6 in unexplained recurrent spontaneous abortion.

Unexplained recurrent spontaneous abortion (URSA) is commonly observed, and seriously affects women's reproductive health. Excessive interleukin-6 (IL-6) production has been shown to frequently occur and relate to URSA pathogenesis. In this study, the miRNA expression profile in peripheral blood mononuclear cells (PBMCs) from URSA patients and normal pregnant (NP) women was assessed by miRNA microarray and real-time quantitative reverse-transcription polymerase chain reaction (qPCR). MiRNA target prediction tools and luciferase reporter assay were used to detect direct binding between miRNAs and IL6. Functional study of administering anti-IL-6 neutralizing antibody and miR-374c-5p mimics to an URSA animal model was performed to evaluate embryo resorption rates. In the results, compared with NP women, the expression of IL-6 increased markedly in PBMCs and decidual tissues at both mRNA and protein levels, while miR-374c-5p expression decreased significantly. Prediction software and luciferase reporter assay showed that miR-374c-5p binds with IL6 3'UTR via the complementary bases. Transfection of miR-374c-5p mimics into an in vitro HeLa cell line significantly downregulated the expression of IL-6, while transfection of the miR-374c-5p inhibitor induced an opposite result. In the URSA mouse model, miR-374c-5p overexpression reduced the embryo resorption rate significantly, accompanied with decreased expression of IL-6 in the decidua. To sum up, downregulated miR-374c-5p was involved in the pathogenesis of URSA by enhancing IL-6 expression. Modulation of miR-374c-5p expression may be used to regulate IL-6 production for the treatment of URSA.

Crosstalk Between Trophoblasts and Decidual Immune Cells: The Cornerstone of Maternal-Fetal Immunotolerance.

The success of pregnancy relies on the fine adjustment of the maternal immune system to tolerate the allogeneic fetus. Trophoblasts carrying paternal antigens are the only fetal-derived cells that come into direct contact with the maternal immune cells at the maternal-fetal interface. The crosstalk between trophoblasts and decidual immune cells (DICs) via cell-cell direct interaction and soluble factors such as chemokines and cytokines is a core event contributing to the unique immunotolerant microenvironment. Abnormal trophoblasts-DICs crosstalk can lead to dysregulated immune situations, which is well known to be a potential cause of a series of pregnancy complications including recurrent spontaneous abortion (RSA), which is the most common one. Immunotherapy has been applied to RSA. However, its development has been far less rapid or mature than that of cancer immunotherapy. Elucidating the mechanism of maternal-fetal immune tolerance, the theoretical basis for RSA immunotherapy, not only helps to understand the establishment and maintenance of normal pregnancy but also provides new therapeutic strategies and promotes the progress of immunotherapy against pregnancy-related diseases caused by disrupted immunotolerance. In this review, we focus on recent progress in the maternal-fetal immune tolerance mediated by trophoblasts-DICs crosstalk and clinical application of immunotherapy in RSA. Advancement in this area will further accelerate the basic research and clinical transformation of reproductive immunity and tumor immunity.

Study of effect and molecule mechanism of Shou Tai Decoction on URSA treatment by regulating function of dendritic cells / 中国免疫学杂志

Objective:To investigate the role of dendritic cells(DC) in unexplained recurrent spontaneous abortion(URSA) and to study the effect and molecular mechanism of Traditional Chinese Medicine Shou Tai Decoction ( STD ) on URSA treatment by regulating the function of DC.Methods:30 cases of normal pregnancy women and 30 cases of URSA patients were taken as control group and URSA group respectively.URSA patients were treated with Shou Tai Decoction.Peripheral blood mononuclear cells were taken from both control group and URSA group before and after STD administration.The proportion of CD11c+HLA-DR+cells,CD11c+CD80+cells and CD11c+CD86+cells in peripheral blood were measured by flow cytometry.Moreover,the mRNA expression of HLA-DR,CD80,CD86 and Indoleamine2,3-dioxygenase( IDO) in venous blood were detected by RT-PCR assay.The protein expression of IDO was detected by Western blot.Furthermore, the cytokines, including IL-12p70 and IL-6, in the blood serum were measured by ELISA.Results:Compared with normal pregnancy women,the proportion of CD11c+HLA-DR+,CD11c+CD80+,CD11c+CD86+cells and the mRNA expression of HLA-DR,CD80,CD86 of URSA patients in peripheral blood were both increased significantly(P<0.05), while the mRNA and protein expression of IDO were decreased markedly(P<0.05).Additionally,the level of IL-12p70 and IL-6 in serum of URSA women were significantly increased ( P<0.01 ) .When compared with URSA patients before STD administration, the proportion of CD11c+HLA-DR+,CD11c+CD80+,CD11c+CD86+cells and the mRNA expression of HLA-DR,CD80,CD86 decreased significantly after STD administration ( P<0.05 ) , while the mRNA and protein expression of IDO increased markedly after STD administration(P<0.05).Meanwhile,compared with before STD administration,serum protein level of IL-12p70 and IL-6 of URSA patients decreased significantly after STD treatment ( P<0.01 ) .Conclusion: The changes of proportion and function of DC were involved in URSA.The regulatory effect of STD on DC proportion and function contribute to the treatment of URSA.