Department of Ophthalmology, UT Southwestern Medical Center, Dallas, TX 75390, USA.
Department of Biomedical Engineering, UT Southwestern Medical Center, Dallas, TX 75390, USA.
Cells. 2024 Jun 25;13(13):1094. doi: 10.3390/cells13131094.
Vimentin has been reported to play diverse roles in cell processes such as spreading, migration, cell-matrix adhesion, and fibrotic transformation. Here, we assess how vimentin impacts cell spreading, morphology, and myofibroblast transformation of human corneal fibroblasts. Overall, although knockout (KO) of vimentin did not dramatically impact corneal fibroblast spreading and mechanical activity (traction force), cell elongation in response to PDGF was reduced in vimentin KO cells as compared to controls. Blocking vimentin polymerization using Withaferin had even more pronounced effects on cell spreading and also inhibited cell-induced matrix contraction. Furthermore, although absence of vimentin did not completely block TGFβ-induced myofibroblast transformation, the degree of transformation and amount of αSMA protein expression was reduced. Proteomics showed that vimentin KO cells cultured in TGFβ had a similar pattern of protein expression as controls. One exception included periostin, an ECM protein associated with wound healing and fibrosis in other cell types, which was highly expressed only in Vim KO cells. We also demonstrate for the first time that LRRC15, a protein previously associated with myofibroblast transformation of cancer-associated fibroblasts, is also expressed by corneal myofibroblasts. Interestingly, proteins associated with LRRC15 in other cell types, such as collagen, fibronectin, β1 integrin and α11 integrin, were also upregulated. Overall, our data show that vimentin impacts both corneal fibroblast spreading and myofibroblast transformation. We also identified novel proteins that may regulate corneal myofibroblast transformation in the presence and/or absence of vimentin.
波形蛋白已被报道在细胞过程中发挥多种作用，如扩散、迁移、细胞-基质黏附以及纤维化转化。在这里，我们评估了波形蛋白如何影响人角膜成纤维细胞的细胞扩展、形态和肌成纤维细胞转化。总的来说，尽管波形蛋白敲除（KO）并没有显著影响角膜成纤维细胞的扩展和机械活性（牵引力），但与对照组相比，波形蛋白 KO 细胞对 PDGF 的反应性细胞伸长减少。使用 Withaferin 阻断波形蛋白聚合对细胞扩展的抑制作用更为明显，并且还抑制了细胞诱导的基质收缩。此外，尽管缺乏波形蛋白并没有完全阻止 TGFβ诱导的肌成纤维细胞转化，但转化的程度和αSMA 蛋白表达的量减少。蛋白质组学显示，在 TGFβ中培养的波形蛋白 KO 细胞与对照具有相似的蛋白质表达模式。一个例外是periostin，一种与其他细胞类型的伤口愈合和纤维化相关的 ECM 蛋白，它仅在 Vim KO 细胞中高度表达。我们还首次证明，LRRC15 是一种先前与癌症相关成纤维细胞的肌成纤维细胞转化相关的蛋白，也由角膜肌成纤维细胞表达。有趣的是，与其他细胞类型中的 LRRC15 相关的蛋白质，如胶原蛋白、纤维连接蛋白、β1 整合素和α11 整合素，也被上调。总的来说，我们的数据表明波形蛋白既影响角膜成纤维细胞的扩展，也影响肌成纤维细胞的转化。我们还鉴定了在存在和/或不存在波形蛋白的情况下可能调节角膜肌成纤维细胞转化的新蛋白。
