原子力显微镜研究粘附分子与细胞膜上整合素分子的相互作用

AFM Measures the Interaction of Integrin with Adhesion Molecule

目的:研究肝癌细胞弹性变化对其表达的整合素分子与配体分子相互作用的影响。方法:以壳聚糖/聚丙烯酰胺水凝胶作为可变基底材料,并将人肝肿瘤细胞(Hep G2)接种到不同软硬度壳聚糖/聚丙烯酰胺水凝胶基底上,利用原子力显微镜力与距离模式定量测定不同软硬基底上生长的Hep G2肝瘤细胞膜表面整合素分子与层粘连蛋白分子之间相互作用力。结果:功能化的原子力显微镜探针与不同软硬基底上生长的细胞所产生的粘附情况不相同,细胞生长在培养皿的为对照组;细胞生长在硬度为1000Pa壳聚糖/聚丙烯酰胺水凝胶基底上的为实验组,表达在Hep G2肝瘤细胞膜上的α6β1整合素与其配体层粘连蛋白相互作用力的大小分别为19±7 p N和38.85±19.7 p N。结论:基底软硬度会影响细胞整合素与配体分子间的相互作用。

Objective： To study the interactions between integrin and their ligand by the hepatocellular carcinoma cell line with elastic changes. Methods： The chitosan/polyacrylamide hydrogel is a variable substrate material, and Hep G2 cells are planted on different rigidity of chitosan/polyacrylamide hydrogen substrates. Cell elasticity of Hep G2 in different rigidity substrate and the interaction force between integrin α6β1 and laminin（LN） under physiological conditions were detected by AFM force distance curve. Results： The main results obtained in this study as follows： The adhesions between atomic force microscope functional probe and the cell grown different soft and hard substrate were not the same. Cells grown in culture dishes were served as control group; cells growth in the hardness of1000 Pa chitosan/polyacrylamide hydrogel substrates for the experimental group. The adhesion proportion of cell is different because of the deviation of rigidity. The interaction force between integrinα6β1 and ligand（LN） are 19±7 p N and 38.85±19.7 p N. Conclusions：Substrate rigidity is a factor which affects the interaction of integrin with adhesion molecule.