Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan 430022, P.R. China.
Oncol Rep. 2013 Nov;30(5):2211-9. doi: 10.3892/or.2013.2687. Epub 2013 Aug 22.
Mesenchymal stem cells (MSCs) are multipotent stem cells with the ability to migrate to sites of inflammation and injury, where they participate in tissue regeneration and repair. The present study aimed to investigate the effects of T cell activation and inflammation on the differentiation of MSCs. Human trabecular bone‑derived MSCs were isolated from patients undergoing total hip replacement, and T cells were isolated and purified from peripheral blood mononuclear cells (PBMCs) using CD3 MicroBeads. MSCs were co‑cultured with activated T cells to mimic the inflammatory microenvironment. MTS assay was used to detect cell proliferation.qRT‑PCR, western blotting, histology and immunohistochemical staining were used to detect the adipo‑/osteo‑specific gene expression and the relative signaling pathway. The MTS results showed that higher concentrations of T cells significantly increased the proliferation of MSCs. Expression of the inflammatory gene IL‑6 was upregulated, while expression of IL‑10 and INFγ was downregulated in MSCs exposed to activated T cells. The results also showed that PHA‑activated T cells significantly upregulated the expression of PPARγ and FABP4 (adipo‑specific genes) in MSCs, but no difference was noted in the expression of RUNX2, osteocalcin and ALP (osteo‑specific genes) at the protein level. T cell treatment and inflammation inhibited the protein expression of TGF‑β1 and the phosphorylation of Smad3, resulting in the weakening of the TGF‑β/Smad pathway and enhancing the adipogenic differentiation of MSCs. The results indicated that PHA‑activated T cells and inflammation could promote adipogenesis without affecting the late stage of osteogenesis of MSCs, by increasing the expression of key adipogenic genes through TGF‑β/Smad3 signaling.
间充质干细胞（MSCs）是具有多能性的干细胞，能够迁移到炎症和损伤部位，参与组织再生和修复。本研究旨在探讨 T 细胞激活和炎症对 MSCs 分化的影响。从接受全髋关节置换术的患者中分离出人小梁骨源性 MSCs，并使用 CD3 MicroBeads 从外周血单核细胞（PBMCs）中分离和纯化 T 细胞。将 MSCs 与激活的 T 细胞共培养，以模拟炎症微环境。使用 MTS 法检测细胞增殖。qRT-PCR、western blot、组织学和免疫组织化学染色用于检测脂肪/成骨特异性基因表达和相关信号通路。MTS 结果表明，较高浓度的 T 细胞可显著增加 MSCs 的增殖。暴露于激活的 T 细胞后，MSC 中炎症基因 IL-6 的表达上调，而 IL-10 和 INFγ 的表达下调。结果还表明，PHA 激活的 T 细胞可显著上调 MSCs 中 PPARγ 和 FABP4（脂肪特异性基因）的表达，但在蛋白质水平上，RUNX2、骨钙素和 ALP（成骨特异性基因）的表达无差异。T 细胞处理和炎症抑制了 TGF-β1 的蛋白表达和 Smad3 的磷酸化，从而削弱了 TGF-β/Smad 通路，并增强了 MSCs 的脂肪生成分化。结果表明，PHA 激活的 T 细胞和炎症可通过增加 TGF-β/Smad3 信号转导中关键脂肪生成基因的表达，促进脂肪生成而不影响 MSCs 成骨后期。
