title: The viscoelastic properties of microvilli are dependent upon the cell-surface molecule.
abstract: We studied at nanometer resolution the viscoelastic properties of microvilli and tethers pulled from myelogenous cells via P-selectin glycoprotein ligand 1 (PSGL-1) and found that in contrast to pure membrane tethers, the viscoelastic properties of microvillus deformations are dependent upon the cell-surface molecule through which load is applied. A laser trap and polymer bead coated with anti-PSGL-1 (KPL-1) were used to apply step loads to microvilli. The lengthening of the microvillus in response to the induced step loads was fitted with a viscoelastic model. The quasi-steady state force on the microvillus at any given length was approximately fourfold lower in cells treated with cytochalasin D or when pulled with concanavalin A-coated rather than KPL-1-coated beads. These data suggest that associations between PSGL-1 and the underlying actin cytoskeleton significantly affect the early stages of leukocyte deformation under flow.
authors.affiliation: Department of Biomedical Engineering, University of Virginia, Box 800759, Charlottesville, VA 22908, USA.
authors.forename: Johanne L
authors.initials: JL
authors.lastname: Python
authors.forename: Kristal O
authors.initials: KO
authors.lastname: Wilson
authors.forename: Jeremy H
authors.initials: JH
authors.lastname: Snook
authors.forename: Bin
authors.initials: B
authors.lastname: Guo
authors.forename: William H
authors.initials: WH
authors.lastname: Guilford
mesh_terms: D002462:Cell Membrane / Q000737:chemistry*; D004548:Elasticity; D018922:HL-60 Cells; D006801:Humans; D007962:Leukocytes / Q000737:chemistry*; D008562:Membrane Glycoproteins / Q000737:chemistry*; D008871:Microvilli / Q000737:chemistry*; D019007:P-Selectin / Q000737:chemistry*; D014783:Viscosity
chemical_list: D008562:Membrane Glycoproteins; D019007:P-Selectin; C084882:P-selectin ligand protein