IL-8刺激L-选择素水解断裂对细胞膜拓扑结构和刚度的影响  

Impacts of IL-8-induced L-selectin shedding on microtopology and stiffness of cell membrane

作　　者：贾潇凌[1,2,3] 王世骐[1,2] 陈娟[1,2] 龙勉[1,2] 

机构地区：[1]中国科学院力学研究所微重力重点实验室,北京100190 [2]中国科学院力学研究所生物力学与生物工程中心,北京100190 [3]北京航空航天大学生物与医学工程学院,北京100191

出　　处：《医用生物力学》2009年第5期379-383,389,共6页Journal of Medical Biomechanics

基　　金：国家自然科学基金资助(30730032和10332060)

摘　　要：目的研究IL-8刺激所致的L-选择素水解断裂是否会引起细胞膜结构和刚度的变化,进而影响L-选择素-配体的反应动力学。方法分别用IL-8、TAPI-0+IL-8和TAPI-0处理本构表达L-选择素的Jurkat细胞,用以构建L-选择素水解断裂、阻断水解断裂和阻断剂对照的细胞-分子模型。采用扫描电镜观察其表面拓扑结构,采用微管吸吮方法测量其刚度。结果与正常组相比,水解断裂组和阻断水解断裂组细胞微绒毛减少、表面趋于光滑,而阻断剂对照组则无明显变化;无论是水解断裂组,阻断水解断裂组还是阻断剂对照组,细胞膜刚度与正常组相比均无显著性差异。结论IL-8刺激所致L-选择素水解断裂会引发细胞膜拓扑结构的变化,进而影响L-选择素-配体反应动力学的变化;而细胞膜刚度未见明显变化,表明载体刚度不是水解断裂引发L-选择素-配体反应动力学变化的因素。Objective To elucidate if IL-8-induced L-selectin shedding is associated with the changes in microtopology and stiffness of cell membrane,which in turn regulates the kinetics of L-selectin binding to its ligands. Method Intact Jurkat cells constitutively expressing L-selectin（Case Ⅰ） were incubated by IL-8（Case Ⅱ）,pre-incubated by TAPI-0 following by incubating with IL-8（Case Ⅲ）,or treated by TAPI-0 alone（Case Ⅳ）.The microtopology and stiffness of cell membrane were measured using electron scanning microscopy and micropipette aspiration assay,respectively. Result The presentation of microvilli on the surface was reduced and cell membrane became smooth in Cases Ⅱ and Ⅲbut not in Case Ⅳ,as compared to that in Case Ⅰ.No significant difference in membrane stiffness was found for all four cases. Conclusions Surface microtopology of a Jurkat cell was modified by IL-8 treatment,which would affect the binding kinetics of L-selectin to its ligands,whereas membrane stiffness retained the same as that for an intact cell,which would not contribute to the kinetics.

关 键 词：白细胞介素-8(IL-8) L-选择素水解断裂 拓扑结构 刚度 动力学 

分 类 号：R318.01[医药卫生—生物医学工程]