Department of Molecular and Internal Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-Ku, Hiroshima, 734-8551, Japan.
Department of Physical Analysis and Therapeutic Sciences, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
Cell Commun Signal. 2023 Sep 21;21(1):247. doi: 10.1186/s12964-023-01099-z.
Nestin, an intermediate filament protein, participates in various pathophysiological processes, including wound healing, angiogenesis, endothelial-mesenchymal transition (EndoMT), and fibrosis. However, the pathophysiological roles of lung nestin-expressing cells remain unclear due to conflicting reports. The objective of this study is to elucidate the characteristics and functions of lung nestin-expressing cells.
We conducted a series of in vitro and in vivo experiments using endothelial cell line MS1 and nestin-GFP mice. This animal model allows for nestin-expressing cell detection without the use of anti-nestin antibodies.
Lung nestin-expressing cells occurred in approximately 0.2% of CD45 cells and was co-expressed with epithelial, endothelial, and mesenchymal cell-surface markers. Importantly, virtually all nestin-expressing cells co-expressed CD31. When compared to lung nestin-nonexpressing endothelial cells, nestin-expressing endothelial cells showed robust angiogenesis with frequent co-expression of PDGFRβ and VEGFR2. During TGFβ-mediated EndoMT, the elevation of Nes mRNA expression preceded that of Col1a1 mRNA, and nestin gene silencing using nestin siRNA resulted in further upregulation of Col1a1 mRNA expression. Furthermore, Notch3 expression was regulated by nestin in vitro and in vivo; nestin siRNA resulted in reduced Notch3 expression accompanied with enhanced EndoMT. Contrary to previous reports, neither Nes mRNA expression nor nestin-expressing cells were increased during pulmonary fibrosis.
Our study showed that (1) lung nestin-expressing cells are an endothelial lineage but are distinct from nestin-nonexpressing endothelial cells; (2) nestin regulates Notch3 and they act collaboratively to regulate angiogenesis, collagen production, and EndoMT; and (3) nestin plays novel roles in lung angiogenesis and fibrosis. Video Abstract.
巢蛋白（Nestin）是一种中间丝蛋白，参与多种病理生理过程，包括伤口愈合、血管生成、内皮-间充质转化（EndoMT）和纤维化。然而，由于相互矛盾的报道，肺巢蛋白表达细胞的病理生理作用仍不清楚。本研究旨在阐明肺巢蛋白表达细胞的特征和功能。
我们使用内皮细胞系 MS1 和 nestin-GFP 小鼠进行了一系列的体外和体内实验。该动物模型允许在不使用抗巢蛋白抗体的情况下检测巢蛋白表达细胞。
肺巢蛋白表达细胞约占 CD45 细胞的 0.2%，并与上皮细胞、内皮细胞和间充质细胞表面标志物共同表达。重要的是，几乎所有的巢蛋白表达细胞都共同表达 CD31。与肺巢蛋白不表达的内皮细胞相比，巢蛋白表达的内皮细胞表现出强烈的血管生成能力，并且经常共同表达 PDGFRβ 和 VEGFR2。在 TGFβ 介导的 EndoMT 中，Nes mRNA 的表达升高先于 Col1a1 mRNA 的表达，使用 nestin siRNA 沉默巢蛋白基因导致 Col1a1 mRNA 的表达进一步上调。此外，Notch3 的表达在体外和体内均受巢蛋白的调节；nestin siRNA 导致 Notch3 表达减少，同时 EndoMT 增强。与之前的报道相反，在肺纤维化过程中，Nes mRNA 的表达或巢蛋白表达细胞并没有增加。
我们的研究表明：（1）肺巢蛋白表达细胞是内皮谱系，但与巢蛋白不表达的内皮细胞不同；（2）巢蛋白调节 Notch3，它们协同作用调节血管生成、胶原产生和 EndoMT；（3）巢蛋白在肺血管生成和纤维化中发挥新的作用。视频摘要。
