Hong Qian¹

Molecular & Cellular Biomechanics, Vol.1, No.4, pp. 267-278, 2004, DOI:10.3970/mcb.2004.001.267

Abstract In recent single-particle tracking (SPT) measurements on Listeria monocytogenes motility in cells [Kuo and McGrath (2000)], the actin-based stochastic dynamics of the bacterium movement has been analyzed statistically in terms of the mean-square displacement (MSD) of the trajectory. We present a stochastic analysis of a simplified polymerization Brownian ratchet (BR) model in which motions are limited by the bacterium movement. Analytical results are obtained and statistical data analyses are investigated. It is shown that the MSD of the stochastic bacterium movement is a monotonic quadratic function while the MSD for detrended trajectories is linear. Both the short-time relaxation and the… More >

Molecular & Cellular Biomechanics, Vol.15, No.1, pp. 21-36, 2018, DOI:10.3970/mcb.2018.015.021

Abstract Dendritic cells (DCs) are the most potent professional antigen presenting cells as now known, which play critical roles in the initiation, programming and regulation of the immune response. Transforming growth factor-β₁ (TGF-β₁), one of the major suppressive cytokines in tumor microenvironment, can deteriorate the biomechanical characteristics and motility of mature dendritic cells (mDCs)，but the underlying molecular mechanisms are not well defined. In this study, the effects of TGF-β₁ on the motilities and T cell priming capabilities of mDCs as well as the molecular regulatory mechanisms were investigated. The results showed that the cytoskeleton (F-actin) organizations of mDCs were abnormally remodeled… More >

A.L. Brock, D.E. Ingber¹

Molecular & Cellular Biomechanics, Vol.2, No.3, pp. 135-144, 2005, DOI:10.3970/mcb.2005.002.135

Abstract The direction in which cells extend new motile processes, such as lamellipodia and filopodia, can be controlled by altering the geometry of extracellular matrix adhesive islands on which individual cells are cultured, thereby altering mechanical interactions between cells and the adhesive substrate [Parker (2002)]. Here we specifically investigate the intracellular molecular signals that mediate the mechanism by which cells selectively extend these processes from the corners of polygonal-shaped adhesive islands. Constitutive activation of the small GTPase Rac within cells cultured on square-shaped islands of fibronectin resulted in the elimination of preferential extension from corners. This loss of directionality was accompanied… More >