Department of Molecular Medicine, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran.
School of Medicine, Shiraz Institute for Cancer Research, Shiraz University of Medical Sciences, Shiraz, Iran.
Cell Biol Int. 2021 Dec;45(12):2544-2556. doi: 10.1002/cbin.11698. Epub 2021 Sep 27.
Indoleamine 2, 3-dioxygenase (IDO) catabolizes tryptophan, mediates immunomodulatory functions, and is released by stromal cells such as mesenchymal stem cells. The aims of this study were to investigate the effects of IDO silencing on immunosuppressive function of adipose-derived mesenchymal stem cells (ASCs), T cells phenotype, and the proliferation/migration of tumor cells. ASCs isolated from adipose tissues of healthy women were transfected with IDO-siRNA. Galectin-3, transforming growth factor-β1, hepatocyte growth factor, and interleukin-10 as immunomodulators were measured in ASCs using qRT-PCR. T cells phenotype, interferon-γ, and interleukin-17 expression were evaluated in peripheral blood lymphocytes (PBLs) cocultured with IDO silenced-ASCs by flow cytometry and qRT-PCR, respectively. Scratch assay was applied to assess the proliferation/migration of MDA-MB-231 cell line. Galectin-3 was upregulated (p ˂ 0.05) while hepatocyte growth factor was downregulated (p ˂ 0.05) in IDO-silenced ASCs compared to control groups. Regulatory T cells were inhibited in PBLs cocultured with IDO-silenced ASCs; also T helper2 was decreased in PBLs cocultured with IDO-silenced ASCs relative to the scramble group. IDO-silenced ASCs caused interferon-γ overexpression but interleukin-17 downregulation in PBLs. The proliferation/migration of MDA-MB-231 was suppressed after exposing to condition media of IDO-silenced ASCs compared with condition media of untransfected (p < 0.01) and scramble-transfected ASCs (p < 0.05). The results exhibited the weakened capacity of IDO-silenced ASCs for suppressing the immune cells and promoting the tumor cells' proliferation/migration. IDO suppression may be utilized as a strategy for cancer treatment. Simultaneous blocking of immunomodulators along with IDO inhibitors may show more effects on boosting the efficiency of immune-based cancer therapies.
吲哚胺 2,3-双加氧酶 (IDO) 分解色氨酸、介导免疫调节功能，并由间充质干细胞等基质细胞释放。本研究旨在探讨 IDO 沉默对脂肪来源间充质干细胞 (ASCs) 免疫抑制功能、T 细胞表型以及肿瘤细胞增殖/迁移的影响。从健康女性的脂肪组织中分离出 ASCs，并用 IDO-siRNA 进行转染。使用 qRT-PCR 检测 ASCs 中半乳糖凝集素-3、转化生长因子-β1、肝细胞生长因子和白细胞介素-10 等免疫调节剂。通过流式细胞术和 qRT-PCR 分别评估 IDO 沉默的 ASCs 与外周血淋巴细胞 (PBLs) 共培养后 T 细胞表型、干扰素-γ 和白细胞介素-17 的表达。划痕试验用于评估 MDA-MB-231 细胞系的增殖/迁移。与对照组相比，IDO 沉默的 ASCs 中半乳糖凝集素-3 上调 (p<0.05)，而肝细胞生长因子下调 (p<0.05)。与对照转染组相比，IDO 沉默的 ASCs 与 PBLs 共培养后抑制调节性 T 细胞；与 scramble 组相比，IDO 沉默的 ASCs 与 PBLs 共培养后 T 辅助 2 减少。IDO 沉默的 ASCs 导致 PBLs 中干扰素-γ 过度表达，但白细胞介素-17 下调。与未转染 (p<0.01) 和 scramble 转染的 ASCs (p<0.05) 的条件培养基相比，暴露于 IDO 沉默的 ASCs 的条件培养基后 MDA-MB-231 的增殖/迁移受到抑制。结果表明，IDO 沉默的 ASCs 抑制免疫细胞和促进肿瘤细胞增殖/迁移的能力减弱。IDO 抑制可作为癌症治疗的一种策略。同时阻断免疫调节剂和 IDO 抑制剂可能会对提高免疫为基础的癌症治疗效率产生更大的影响。
