Effect of contact time and force on monocyte adhesion to vascular endothelium.

TitleEffect of contact time and force on monocyte adhesion to vascular endothelium.
Publication TypeJournal Article
Year of Publication2001
AuthorsRinker, KD, Prabhakar, V, and Truskey, GA
JournalBiophysical Journal
Start Page1722
Pagination1722 - 1732
Date Published04/2001

In this study we examined whether monocytic cell attachment to vascular endothelium was affected by elevating shear stress at a constant shear rate. Contact time, which is inversely related to the shear rate, was fixed and viscosity elevated with dextran to increase the shear stress (and hence the net force on the cell) independently of shear rate. At a fixed contact time, tethering frequencies increased, rolling velocities decreased, and median arrest durations increased with increasing shear stress. Rolling and short arrests (< 0.2 s) were well fit by a single exponential consistent with adhesion via the formation of a single additional bond. The cell dissociation constant, k(off), increased when the shear stress was elevated at constant shear rate. Firmly adherent cells arresting for at least 0.2 s were well fit by a stochastic model involving dissociation from multiple bonds. Therefore, at a fixed contact time and increasing shear stress, bonds formed more frequently for rolling cells resulting in more short arrests, and more bonds formed for firmly arresting cells resulting in longer arrest durations. Possible mechanisms for this increased adhesion include greater monocyte deformation and/or more frequent penetration of microvilli through steric and charge barriers.

Short TitleBiophysical Journal