title: Membrane tethers formed from blood cells with available area and determination of their adhesion energy.
abstract: Fundamental to all mammalian cells is the adherence of the lipid bilayer membrane to the underlying membrane associated cytoskeleton. To investigate this adhesion, we physically detach the lipid membrane from the cell by mechanically forming membrane tethers. For the most part these have been tethers formed from either neutrophils or red cells. Here we do a simple thermodynamic analysis of the tether formation process using the entire cell, including tether, as the control volume. For a neutrophil, we show that the total adhesion energy per unit area between lipid membrane and cytoskeleton depends on the square of the tether force. For a flaccid red cell, we show that the total adhesion energy minus the tension in the spectrin cytoskeleton depends also on the square of the tether force. Finally, we discuss briefly the viscous flow of membrane. Using published data we calculate and compare values for the various adhesion energies and viscosities.
authors.affiliation: Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708-0300, USA. r.hochmuth@duke.edu
authors.forename: Robert M
authors.initials: RM
authors.lastname: Hochmuth
authors.forename: Warren D
authors.initials: WD
authors.lastname: Marcus
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D001773:Blood Cells / Q000166:cytology* / Q000502:physiology*; D002448:Cell Adhesion / Q000502:physiology*; D003599:Cytoskeleton / Q000502:physiology; D004912:Erythrocytes / Q000166:cytology / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D008563:Membrane Lipids / Q000502:physiology; D008871:Microvilli / Q000502:physiology; D009504:Neutrophils / Q000166:cytology / Q000502:physiology; D013816:Thermodynamics; D014783:Viscosity
chemical_list: D008563:Membrane Lipids