Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, College of Bioengineering, Chongqing, China.
Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, College of Bioengineering, Chongqing, China.
Colloids Surf B Biointerfaces. 2022 Oct;218:112784. doi: 10.1016/j.colsurfb.2022.112784. Epub 2022 Aug 24.
Mechanical properties play key roles in the immune system, especially the activation, transformation and subsequent effector responses of immune cells. As transmembrane adhesion receptors, integrins mediate the adhesion events of both cells and cell-extracellular matrix (ECM). Integrin affinity would influence the crosslinking of cytoskeleton, leading to the change of elastic properties of cells. In this study, the cells were treated with F-actin destabilizing agent Cytochalasin-D (Cyt-D), fixed by Glutaraldehyde, and cultivated in hypotonic solution respectively. We used Atomic force microscopy (AFM) to quantitatively measure the elasticity of Jurkat cells and adhesion properties between integrins and vascular cell adhesion molecule-1 (VCAM-1), and immunofluorescence to study the alteration of cytoskeleton. Glutaraldehyde had a positive effect on the adhesion force and Young's modulus. However, these mechanical properties decreased in a hypotonic environment, confirming the findings of cellular physiological structure. There was no significant difference in the bond strength and elasticity of Jurkat cells treated with Cytochalasin-D, probably because of lower importance of actin in suspension cells. All the treatments in this study pose a negative effect on the adhesion probability between integrins and VCAM-1, which demonstrates the effect of structural alteration of the cytoskeleton on the conformation of integrin. Clear consistency between adhesion force of integrin/VCAM-1 bond and Young's modulus of Jurkat cells was shown. Our results further demonstrated the relationship between cytoskeleton and integrin-ligand by mechanical characteristics.
力学性能在免疫系统中起着关键作用，尤其是免疫细胞的激活、转化和后续效应反应。作为跨膜黏附受体，整合素介导细胞和细胞-细胞外基质（ECM）之间的黏附事件。整合素亲和力会影响细胞骨架的交联，导致细胞弹性特性的改变。在这项研究中，用细胞松弛素 D（Cyt-D）处理细胞以破坏 F-肌动蛋白，用戊二醛固定细胞，然后分别在低渗溶液中培养。我们使用原子力显微镜（AFM）定量测量 Jurkat 细胞的弹性和整合素与血管细胞黏附分子-1（VCAM-1）之间的黏附特性，并通过免疫荧光研究细胞骨架的变化。戊二醛对黏附力和杨氏模量有积极影响。然而，在低渗环境下，这些力学性能下降，证实了细胞生理结构的变化。用细胞松弛素 D 处理的 Jurkat 细胞的键强度和弹性没有显著差异，可能是因为悬浮细胞中肌动蛋白的重要性较低。本研究中的所有处理都对整合素和 VCAM-1 之间的黏附概率产生负面影响，这表明细胞骨架结构的改变对整合素构象有影响。整合素/VCAM-1 键的黏附力和 Jurkat 细胞的杨氏模量之间显示出清晰的一致性。我们的结果进一步通过力学特性证明了细胞骨架和整合素-配体之间的关系。
