Objectives

Uncontrolled TH17 differentiation has been suggested to play a role in the pathogenesis of pregnancy loss. We recently showed that menstrual blood stromal/stem cells (MenSCs) alter functional features of natural killer cells. Here, we hypothesized that MenSCs could modulate differentiation of TH17 cells.

Method

MenSCs were collected from 18 apparently healthy women and characterized. Bone marrow mesenchymal stem cells (BMSCs) served as a control. TH17 polarization and proliferation of purified T CD4+ cells were assessed by flow cytometry in a well-defined co-culture system containing T CD4+ cells and MenSCs or BMSCs. Indoleamine 2,3-Dioxygenase (IDO) activity was evaluated in MenSC and BMSC culture supernatants by a colorimetric assay. The impact of MenSCs on expression of transcription factors, RORC, T-bet, Gata3, NRP-1 and Helios were studied by qPCR.

Results

MenSCs significantly inhibited TH17 differentiation (p = 0.0383) and percentage of the cells co-expressing IL-17 and IFN-γ (p = 0.0023). PGE2 blockade significantly reduced percentage and proliferation of T CD4+IL-17+ (p = 0.003, p = 0.0018), T CD4+ IFN-γ+ (p = 0.002, p = 0.0022) and T CD4+IL-17+ IFN-γ+ (p = 0.004, p = 0.02) cells. MenSCs produced a considerable activity of IDO (p = 0.0002), induced a significant rise in the Treg frequency (p = 0.0091) and a sharp increase in TH17/Tregs ratio (p = 0.0022). MenSCs increased expression of NRP1 (p = 0.001), while downregulated expression of RORC in T cells (p = 0.001).

Conclusion

Our results suggest a supportive role for MenSCs in establishing a pregnancy-friendly microenvironment in the uterus and put forth the idea that inherent abnormalities of MenSCs may be a basis for dysregulated endometrial immune network leading to pregnancy loss.

中文翻译：

---

MneSCs 通过抑制 TH17 极化在建立对怀孕友好的微环境中发挥支持作用

目标

已表明不受控制的 TH17 分化在流产的发病机制中发挥作用。我们最近表明，经血基质/干细胞 (MenSCs) 会改变自然杀伤细胞的功能特征。在这里，我们假设 MenSCs 可以调节 TH17 细胞的分化。

方法

从 18 名明显健康的女性中收集 MenSCs 并对其进行表征。骨髓间充质干细胞 (BMSC) 作为对照。纯化的 T CD4+ 细胞的 TH17 极化和增殖通过流式细胞术在包含 T CD4+ 细胞和 MenSC 或 BMSC 的明确共培养系统中进行评估。通过比色法在 MenSC 和 BMSC 培养物上清液中评估吲哚胺 2,3-双加氧酶 (IDO) 活性。通过 qPCR 研究了 MenSCs 对转录因子、RORC、T-bet、Gata3、NRP-1 和 Helios 表达的影响。

结果

MenSCs 显着抑制 TH17 分化（p = 0.0383）和共表达 IL-17 和 IFN-γ 的细胞百分比（p = 0.0023）。PGE2 阻断显着降低了 T CD4+IL-17+ (p = 0.003, p = 0.0018)、T CD4+ IFN-γ+ (p = 0.002, p = 0.0022) 和 T CD4+IL-17+ IFN-的百分比和增殖γ+ (p = 0.004, p = 0.02) 细胞。MenSCs 产生相当大的 IDO 活性（p = 0.0002），诱导 Treg 频率显着升高（p = 0.0091）和 TH17/Tregs 比率急剧增加（p = 0.0022）。MenSCs 增加 NRP1 的表达（p = 0.001），同时下调 T 细胞中 RORC 的表达（p = 0.001）。

结论

我们的研究结果表明，MenSCs 在子宫内建立有利于怀孕的微环境中发挥支持作用，并提出 MenSCs 的固有异常可能是子宫内膜免疫网络失调导致流产的基础。