Wang Kai, Du Boxiang, Zhang Yan, Wu Congyou, Wang Xiuli, Zhang Xu, Wang Liwei
School of Medicine, Tongji University, Shanghai 200092, China.
Department of Anesthesiology, Xuzhou Central Hospital, Jiangsu 221009, China.
Stem Cells Int. 2021 Jul 29;2021:9992381. doi: 10.1155/2021/9992381. eCollection 2021.
Acute respiratory distress syndrome (ARDS) is difficult to treat and has a high mortality rate. Mesenchymal stem cells (MSCs) have an important therapeutic effect in ARDS. While the mechanism of MSC migration to the lungs remains unclear, the role of MSCs is of great clinical significance. To this end, we constructed vimentin knockout mice, extracted bone MSCs from the mice, and used them for the treatment of LPS-induced ARDS. H&E staining and Masson staining of mouse lung tissue allowed us to assess the degree of damage and fibrosis of mouse lung tissue. By measuring serum TNF-, TGF-, and INF-, we were able to monitor the release of inflammatory factors. Finally, through immunoprecipitation and gene knockout experiments, we identified upstream molecules that regulate vimentin and elucidated the mechanism that mediates MSC migration. As a result, we found that MSCs from wild-type mice can significantly alleviate ARDS and reduce lung inflammation, while vimentin gene knockout reduced the therapeutic effect of MSCs in ARDS. Cytological experiments showed that vimentin gene knockout can significantly inhibit the migration of MSCs and showed that it changes the proliferation and differentiation status of MSCs. Further experiments found that vimentin's regulation of MSC migration is mainly mediated by Rab7a. Rab7a knockout blocked the migration of MSCs and weakened the therapeutic effect of MSCs in ARDS. In conclusion, we have shown that the Vimentin-Rab7a pathway mediates migration of MSCs and leads to therapeutic effects in ARDS.
急性呼吸窘迫综合征（ARDS）难以治疗且死亡率高。间充质干细胞（MSCs）在ARDS中具有重要的治疗作用。虽然MSCs迁移至肺部的机制尚不清楚，但MSCs的作用具有重大临床意义。为此，我们构建了波形蛋白基因敲除小鼠，从小鼠体内提取骨髓间充质干细胞，并将其用于治疗脂多糖诱导的ARDS。通过对小鼠肺组织进行苏木精-伊红（H&E）染色和Masson染色，我们能够评估小鼠肺组织的损伤程度和纤维化程度。通过检测血清肿瘤坏死因子-α（TNF-α）、转化生长因子-β（TGF-β）和干扰素-γ（INF-γ），我们能够监测炎症因子的释放情况。最后，通过免疫沉淀和基因敲除实验，我们鉴定出调节波形蛋白的上游分子，并阐明了介导MSCs迁移的机制。结果，我们发现野生型小鼠的MSCs能够显著缓解ARDS并减轻肺部炎症，而波形蛋白基因敲除则降低了MSCs在ARDS中的治疗效果。细胞学实验表明，波形蛋白基因敲除能够显著抑制MSCs的迁移，并表明其改变了MSCs的增殖和分化状态。进一步实验发现，波形蛋白对MSCs迁移的调节主要由Rab7a介导。Rab7a基因敲除阻断了MSCs的迁移，并削弱了MSCs在ARDS中的治疗效果。总之，我们表明波形蛋白-Rab7a通路介导了MSCs的迁移，并在ARDS中产生治疗效果。
