Distinct Kinetics Features of LFA-1 and Mac-1 in Neutrophil Activation

摘要：

　　LFA-1 and Mac-1,two β2 integrin members constitutively expressed on neutrophils,mediate leukocyte recruitment cascade by binding to the same ligand of ICAM-1.The slow rolling and firm adhesion of leukocytes rely on LFA-1 while the cell crawling is dependent on Mac-1.We hypothesized that their distinct roles are likely attributed to the differences in the binding kinetics or in the diverse responses of outside-in and inside-out signaling.In this study,we compared the ICAM-1 binding features between soluble or membrane-expressed LFA-1 and Mac-1 with different affinity conformation using optical trap technique.Our data indicated that the affinity up-regulation from wide type (WT) to high affinity (HA) is off-rate dependent for LFA-1 but on-rate dependent for Mac-1.The structural bases of this new finding were found to be consistent with our previous simulations.These results furthered our understanding in their function differences under shear flow.

关键词： LFA-1 Mac-1 ICAM-1 on-rate off-rate

作者: Ning Li Debin Mao Yixin Gong Shouqin Lü Yan Zhang Mian Long

作者单位: Key Laboratory of Microgravity(National Microgravity Laboratory), Institute of Mechanics, Chinese Academy of Sciences,Center of Biomechanics and Bioengineering, Institute of Mechanics, Chinese Academy of Sciences, Beijing, P. R China

会议类型: 国际会议

会议名称: World Congress on Medical Physics and Biomedical Engineering (2012年医学物理及生物医学工程国际会议(IFMBE))

会议地点: 北京

会议语种:英文

页码: 139-142

在线出版日期: 2012-05-26（万方平台首次上网日期，不代表论文的发表时间）