title: Mechanisms for flow-enhanced cell adhesion.
abstract: Cell adhesion is mediated by specific receptor-ligand bonds. In several biological systems, increasing flow has been observed to enhance cell adhesion despite the increasing dislodging fluid shear forces. Flow-enhanced cell adhesion includes several aspects: flow augments the initial tethering of flowing cells to a stationary surface, slows the velocity and increases the regularity of rolling cells, and increases the number of rollingly adherent cells. Mechanisms for this intriguing phenomenon may include transport-dependent acceleration of bond formation and force-dependent deceleration of bond dissociation. The former includes three distinct transport modes: sliding of cell bottom on the surface, Brownian motion of the cell, and rotational diffusion of the interacting molecules. The latter involves a recently demonstrated counterintuitive behavior called catch bonds where force prolongs rather than shortens the lifetimes of receptor-ligand bonds. In this article, we summarize our recently published data that used dimensional analysis and mutational analysis to elucidate the above mechanisms for flow-enhanced leukocyte adhesion mediated by L-selectin-ligand interactions.
authors.affiliation: Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta GA 30332, USA. cheng.zhu@bme.gatech.edu
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhu
authors.forename: Tadayuki
authors.initials: T
authors.lastname: Yago
authors.forename: Jizhong
authors.initials: J
authors.lastname: Lou
authors.forename: Veronika I
authors.initials: VI
authors.lastname: Zarnitsyna
authors.forename: Rodger P
authors.initials: RP
authors.lastname: McEver
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D002448:Cell Adhesion / Q000502:physiology*; D002465:Cell Movement; D003198:Computer Simulation; D006801:Humans; D007962:Leukocytes / Q000502:physiology*; D040542:Mechanotransduction, Cellular / Q000502:physiology*; D008955:Models, Cardiovascular; D033081:Shear Strength