骨髓间充质干细胞通过SPI-6调节DCs功能改善哮喘的机制研究

树突状细胞（DCs）作为最强的抗原递呈细胞在哮喘发生、发展中起着重要作用，对其深入研究有望突破目前哮喘的治疗瓶颈。在前期实验中，我们发现输注骨髓间充质干细胞（BMMSCs）可通过调节DCs功能进而改善哮喘模型的病情。随后我们体外筛查了与DCs作用后BMMSCs中多种细胞因子及蛋白的转录水平，发现丝氨酸蛋白酶抑制剂-6（SPI-6）转录水平明显升高，结合文献报道，推测SPI-6是BMMSCs作用于DCs的关键，其机制是通过抑制颗粒酶等丝氨酸蛋白酶的活性而起到抗凋亡的作用。为进一步探索其机制，我们用SPI6-/-和CD11c DTR小鼠进行实验，通过FACS、定量PCR、蛋白印迹、基因转染等手段，从转录、翻译、细胞活性等水平探索BMMSCs作用于DCs的机制，为揭示BMMSCs和DCs在哮喘治疗中发挥的作用提供依据，也为哮喘的靶向治疗提供新的思路。

Dendritic cells(DCs)，as the most potent antigen presenting cells, play important role in initiation and progression of asthma。Deeper studies on the function of DCs in asthma will give us better understanding of the disease, hence benefit future potential therapeutic stratagy.Our preliminary data show that transfusion of BMMSCs alleviates asthma through downregulation of DC functions. We further screened cytokines and multiple regulatory proteins in DC pretreated with BMMSCs at mRNA levels and found SPI-6 significantly increased in DCs co-cultured with BMMSCs. Based on published data, we hypothessize that upregulation of SPI-6 is the key change in BMMSC conditioned DC function. SPI-6 upregulation leads to decreased level of apoptosis through inhibition of serine proteinases, e.g. Granzyme B.To further characterize the role of SPI-6 in this model, we propose using SPI-6-/- and CD11c DTR transgenic mice as our animal model. We will adopt multiple tenchniques including FACS, qRT-PCR, Wertern blotand gene transfection to study the role of SPI-6 in BMMSC conditioned DC functions at transcription, translation and cellular levels. Hopefully we will adress the molecular mechanism underlying BMMSC regulatiion of DC functions and provide experimental evidence for futher therapeutic stratagies.