Shear force-induced activation of integrin LFA-1 by chemokine CXCL12 under flows
10.16156/j.1004-7220.2017.06.011
- VernacularTitle:流体剪应力作用下趋化因子CXCL12诱导的白细胞整合素LFA-1的激活
- Author:
Dai-Lin CHEN
1
;
Jian-Hua WU
;
Ying FANG
Author Information
1. 华南理工大学生物科学与工程学院
- Keywords:
Lymphocyte function-associated antigen 1 (LFA-1);
Chemokines CXCL12;
Integrin activation;
Receptor-ligand interaction;
Cell adhesion
- From:
Journal of Medical Biomechanics
2017;32(6):548-554
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the activate process of lymphocyte function-associated antigen 1 (LFA-1) triggered by chemokine under shear stresses.Methods Jurkat cells were perfused over ICAM-1 in the parallel-plate flow under 10-30 mPa shear stresses.The effects of soluble and immobilized Chemokines on transient adhesion behavior of Jurkat cells were observed and analyzed to obtain their tether characteristics.Results The immobilized CXCL12 could mediate brief tether (0.13-0.2 s) of Jurkat cells under flow.Only immobilized CXCL12 could effectively activate LFA-1 on Jurkat cells to bind ICAM-1,and then enhance cell adhesion fraction and greatly prolong the tether time (0.8-1.2 s).Two distinct activation states of LFA-1/ICAM-1 were reflected by their dissociation rate k1 (1.09-1.24 s-1) and k2 (0.28-0.7 s-1),respectively.The shear stress would affect the transient adhesion behavior of cells through regulation of k2 andβ (the contribution ratio of high affinity to total tether time).Conclusions Shear stress can rapidly trigger LFA-1 activation in 0.2 s through G protein coupled receptors induced by chemokine CXCL12,and further regulate the whole adhesion process of leukocyte.These research findings will contribute to further understanding the integrin activation mechanism of chemokine-force cooperative regulation.
