TGF-β1对成人骨髓CD105~+间充质干细胞增殖与分化的影响

目的分离并鉴定成人骨髓间充质干细胞(mesenchymalstemcells,MSCs),研究TGFβ1对骨髓MSCs增殖与分化的影响。方法分离成人骨髓单个核细胞;MACS磁珠分选CD105+细胞;FACS检测其免疫表型;诱导分选的CD105+细胞向脂肪及成骨细胞分化,油红O染色、VonKossa染色及RTPCR检测脂肪细胞及成骨细胞;观察TGFβ1对分选出的CD105+细胞分化与增殖的影响;免疫荧光染色检测诱导后的脂肪细胞CD105的表达情况;MTT法检测TGFβ1对CD105+细胞增殖的影响。结果成人骨髓来源的CD105+细胞体外可向脂肪及成骨细胞分化;在向脂肪细胞分化过程中,加入1～50ng/mLTGFβ1后,成脂诱导体系中无脂肪细胞出现;在向成骨诱导过程中,加入20ng/mLTGFβ1后,钙化基质沉淀明显降低;在脂肪诱导体系中,MTT染色检测显示TGFβ1对CD105+细胞的增殖有明显促进作用(P<0.05)。结论TGFβ1抑制成人骨髓源CD105+MSCs向脂肪及成骨细胞分化,在向脂肪诱导过程中,TGFβ1促进MSCs的增殖。

Role of TGF-β1 on differentiation and proliferation of adult bone marrow-derived CD105+ mesenchymal stem cells

Objective To investigate the role of TGF-β1 on proliferation and differentiation of CD105 + mesenchymal stem cells derived from adult bone marrow. Methods Mesenchymal stem cells were sorted by MACS CD105 micromagnetic beads and phenotyped by FACS. The differentiation of CD105 + cells into adipocytes and osteocytes under differentiation culture was induced and determined by RT-PCR, staining of Oil red O and Von Kossa, respectively. The proliferation assay was performed with MTT method. The expression of CD105 was detected by immunofluorescent staining. Results Sorted CD105 + mesenchymal stem cells derived from adult bone marrow could differentiate into adipocytes and osteocytes under different differentiation culture conditions. Differentiation into adipocytes could be inhibited by TGF-β1 at the dose of 1～50 μg/L while accumulation of calcium was only inhibited by higher dosage of TGF-β1 (≥20 μg/L). In the adipocytes differentiation culture, TGF-β1 could promote mesenchymal stem cells proliferation while inhibiting their differentiation. Conclusion TGF-β1 could inhibit the differentiation of CD105 + mesenchymal stem cells into adipocytes and osteocytes and enhance cell proliferation under adipocytes differentiation.