雌激素缺乏导致的骨质疏松发病过程中T淋巴细胞对骨髓间充质干细胞增殖和成骨分化的影响及与TNF-α的关系

Effect of T-lymphocytes on Cell Proliferation and Osteogenic Differentiation of Bone Marrow-derived Mesenchymal Stem Cells

探讨骨质疏松发病过程中T淋巴细胞对骨髓间充质干细胞(bone marrow-derived mesenchymal stem cells,BMMSC)增殖分化的影响。选用健康雌性小鼠行双侧卵巢切除术(ovariectomy,OVX),建立绝经后骨质疏松模型。选用同一批次健康小鼠行双侧卵巢脂肪组织部分切除,建立假手术组(sham),Micro-CT确立模型成功建立。将sham组、OVX组、sham+anti-TNFα组、OVX+anti-TNFα组中T淋巴细胞与BMMSC共培养,ELISA检测sham组与OVX组T淋巴细胞上清液中TNF-α表达的差异,MTT法检测四组共培养体系中BMMSC生长曲线;成骨诱导后碱性磷酸酶和钙化结节茜素红染色法检测BMMSC成骨能力差异;RT-PCR检测小鼠BMMSC成骨相关基因Runx2、碱性磷酸酶(alkaline phosphatase,ALP)的表达。结果显示,与sham组相比,OVX组中BMMSC的增殖受到了抑制,成骨分化减弱(P<0.05),OVX anti-TNF-α刺激组较OVX组增殖显著升高(P<0.05),成骨分化能力显著增强(P<0.05)。以上结果证明,在雌激素缺乏下的T淋巴细胞能影响BMMSC增殖及成骨分化能力,这可能与T淋巴细胞表达TNF-α增强相关。

To investigate the effect of T-lymphocytes on the cell proliferation and osteogenic differentiation of bone marrow-derived mesenchymal stem cells （BMMSC）, the bone marrow-derived mesenchymal stem cell was co-cultured with T-lymphocytes from the sham, OVX group, sham＋anti-TNF-α and OVX＋anti-TNF-α group. The MTT method was used to analyze the growth curves of BMMSC. After osteogenic induction, calcium nodules were observed by alizarin red staining and alkaline phosphatase staining. The expression levels of BMMSC osteogenesis related genes, for instance, Runx2, OCN were measured by RT-PCR. Compared with sham group, the proliferation capacity of BMMSC in OVX group was declined, and the osteogenic potential was decreased. Compared with OVX group, the proliferation capacity of BMMSC in OVX anti-TNF-α group was increased, and the osteogenic potential was enhanced. The results demonstrated that T-lymphocytes might influence the osteogenic activity of BMMSC by inhibiting proliferation and osteogenic differentiation increased expression of TNF-α by T-lymphocytes.