Galectin-3/Notch信号介导骨髓间充质干细胞缺陷参与再生障碍性贫血发病的作用机制研究

Abnormality of bone marrow mesenchymal stromal cells (BM-MSCs) play a central role in the pathogenesis of aplastic anaemia (AA). Galectin-3/Notch signaling pathway was involved in the process of cell differentiation and immune-regulation. Our preliminary data have demonstrated that decreased Gal-3 expression in BM-MSCs from AA patients, accompanied by increased adipogenic differentiation capability and decreased immunomodulatory function. Meanwhile, Gal-3 and Notch signaling were involved in the adipogenic differentiation of BM-MSCs. To this end, we hypothesize that a cross-talk between Gal-3 and Notch signaling regulates the function of BM-MSCs, which was responsible for the pathological progress of AA. To test this hypothesis, we measure Gal-3 levels in BM plasma and BM-MSCs, and evaluate the correlation of Gal-3 levels with related clinical features in newly diagnosed AA patients. Then, we interfere the interaction of Gal-3 and Notch signaling by recombination human Gal-3 (rhGal-3), lentivirus transfection and siRNA, and detect the adipogenic differentiation capability and immune regulation function of BM-MSCs. Subsequently, by western blot, ChIP and RNA-SEQ technology, we observe the expression or activation of key factors in the signal pathway, to analyze the potential molecular mechanisms. Finally, we confirm the role of Gal-3/Notch signaling in vivo. Our results will reveal the molecular mechanisms contributing to BM-MSCs defects in AA, providing new ideas and theoretical basis in the pathogenesis of AA.

骨髓间充质干细胞（BM-MSCs）缺陷在再生障碍性贫血（AA）发病中起重要作用，Gal-3/Notch信号参与多种细胞分化和免疫调控过程。我们前期研究发现AA中BM-MSCs Gal-3表达降低、成脂能力增强、免疫调控能力减弱；Gal-3、Notch在其成脂过程中表达发生改变。据此，我们提出假说：Gal-3与Notch结合，介导BM-MSCs成脂分化和免疫调控异常参与AA发病。为验证假说：我们分析AA骨髓微环境和BM-MSCs中Gal-3/Notch表达与疾病参数相关性；在细胞和小鼠模型中，通过rhGal-3、慢病毒转染和siRNA干预BM-MSCs中Gal-3表达，检测成脂分化和免疫调控改变；western blot、ChIP和RNA-SEQ等手段检测信号关键因子表达和激活，探寻其分子机制。进一步揭示Gal-3/Notch、BM-MSCs缺陷和AA关系，为AA防治提供新思路和理论依据。

骨髓间充质干细胞（BM-MSCs）缺陷和骨髓微环境异常在再生障碍性贫血（AA）发病中起重要作用，在本基金资助下，我们试图从不同角度探讨其发病机制，主要研究成果如下：1.课题组进一步探讨MSCs在AA疾病中的作用，我们筛选出高活性VCAM-1+ MSCs，发现其有更强大免疫抑制功能，在AA小鼠模型中能够减轻其病理生理进程，同时结合MSCs免疫抑制作用，我们系统计较了不同代次MSCs在免疫系统疾病（GVHD）中的功效，发现不同代次MSCs仍有很强的免疫抑制作用。2.探讨骨髓微环境在造血分化中的作用，我们专注于ITP-Exo在巨核细胞产板作用，发现ITP-Exo能够通过细胞凋亡途径抑制巨核细胞产板功能。3.我们试图进一步探讨MSCs造血支持等功能机制，我们通过不同小分子组合（JNKi、DAC）诱导hESCs向MSCs分化，揭示其可能造血机制并构建MSCs体外分化体系，为临床转化提供理论支撑。4.课题结合临床前沿，探讨了循环肿瘤细胞（CTC）相关问题，我们系统地修改了技术参数的范围，提高了CTC早期癌症检测的准确性。