Department of Cardiovascular Sciences, University of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield Hospital, Leicester LE3 9QP, United Kingdom.
Horizon Discovery Ltd., 8100 Cambridge Research Park, Cambridge CB25 9TL, United Kingdom.
Biochim Biophys Acta Mol Cell Res. 2023 Aug;1870(6):119479. doi: 10.1016/j.bbamcr.2023.119479. Epub 2023 Apr 24.
The large extracellular matrix protein SVEP1 mediates cell adhesion via integrin α9β1. Recent studies have identified an association between a missense variant in SVEP1 and increased risk of coronary artery disease (CAD) in humans and in mice Svep1 deficiency alters the development of atherosclerotic plaques. However how SVEP1 functionally contributes to CAD pathogenesis is not fully understood. Monocyte recruitment and differentiation to macrophages is a key step in the development of atherosclerosis. Here, we investigated the requirement for SVEP1 in this process.
SVEP1 expression was measured during monocyte-macrophage differentiation in primary monocytes and THP-1 human monocytic cells. SVEP1 knockout THP-1 cell lines and the dual integrin α4β1/α9β1 inhibitor, BOP, were utilised to investigate the effect of these proteins in THP-1 cell adhesion, migration and cell spreading assays. Subsequent activation of downstream integrin signalling intermediaries was quantified by western blotting.
SVEP1 gene expression increases in monocyte to macrophage differentiation in human primary monocytes and THP-1 cells. Using two SVEP1 knockout THP-1 cells we observed reduction in monocyte adhesion, migration, and cell spreading compared to control cells. Similar results were found with integrin α4β1/α9β1 inhibition. We demonstrate reduced activity of Rho and Rac1 in SVEP1 knockout THP-1 cells.
SVEP1 regulates monocyte recruitment and differentiation phenotypes through an integrin α4β1/α9β1 dependent mechanism.
These results describe a novel role for SVEP1 in monocyte behaviour relevant to CAD pathophysiology.
大细胞外基质蛋白 SVEP1 通过整合素 α9β1 介导细胞黏附。最近的研究表明，SVEP1 中的一个错义变异与人类和小鼠的冠状动脉疾病 (CAD) 风险增加有关，并且 Svep1 缺陷改变了动脉粥样硬化斑块的发展。然而，SVEP1 如何在 CAD 发病机制中发挥功能尚不完全清楚。单核细胞募集和分化为巨噬细胞是动脉粥样硬化发展的关键步骤。在这里，我们研究了 SVEP1 在这个过程中的必要性。
在原代单核细胞和 THP-1 人单核细胞中，测量单核细胞-巨噬细胞分化过程中 SVEP1 的表达。利用 SVEP1 敲除 THP-1 细胞系和双重整合素 α4β1/α9β1 抑制剂 BOP，研究这些蛋白在 THP-1 细胞黏附、迁移和细胞铺展实验中的作用。随后通过 Western blot 定量下游整合素信号转导中间产物的激活。
在人类原代单核细胞和 THP-1 细胞中，单核细胞向巨噬细胞分化过程中 SVEP1 基因表达增加。我们使用两种 SVEP1 敲除 THP-1 细胞，与对照细胞相比，观察到单核细胞黏附、迁移和细胞铺展减少。整合素 α4β1/α9β1 抑制也得到了类似的结果。我们证明 SVEP1 敲除 THP-1 细胞中 Rho 和 Rac1 的活性降低。
SVEP1 通过整合素 α4β1/α9β1 依赖性机制调节单核细胞募集和分化表型。
这些结果描述了 SVEP1 在与 CAD 病理生理学相关的单核细胞行为中的新作用。
