title: Dynamic adhesion of T lymphocytes to endothelial cells revealed by atomic force microscopy.
abstract: The recruitment of T lymphocytes to lymphoid organs or sites of inflammation is a crucial step in adaptive immunity. These processes require endothelial activation and expression of adhesion molecules, including E- and P-selectins, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1). However, the complete characterization of the adhesion strength and dynamics between lymphocytes and endothelial cells has been hampered by the lack of sensitive quantitative techniques. Here we report on the application of atomic force microscopy to characterize the interaction between individual pairs of living T lymphocytes (i.e., Jurkat cells) and human umbilical vein endothelial cells (HUVECs). The detachment of individual cell-cell conjugates was a complex process involving several step-like rupture events and the viscoelastic deformation of cells on the scale of several microns. Adhesion between Jurkat cells and activated endothelial cells increased with compression force and contact time, with the most dramatic changes occurring within the first half second of contact. After 0.25 sec of contact, E-selectin, ICAM-1, and VCAM-1 contributed to 18%, 39%, and 41% of total adhesion strength, respectively, suggesting that ICAM-1 and VCAM-1 contributed more than the selectins in supporting cell attachment.
authors.affiliation: Department of Physiology and Biophysics, University of Miami School of Medicine, 1600 NW 10th Avenue, Miami, Florida 33136, USA. xzhang@cbr.med.harvard.edu
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Zhang
authors.forename: Ewa P
authors.initials: EP
authors.lastname: Wojcikiewicz
authors.forename: Vincent T
authors.initials: VT
authors.lastname: Moy
mesh_terms: D002448:Cell Adhesion / Q000502:physiology*; D002450:Cell Communication / Q000502:physiology*; D044842:Cullin Proteins / Q000378:metabolism; D019040:E-Selectin / Q000378:metabolism; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D019169:Jurkat Cells; D018625:Microscopy, Atomic Force / Q000379:methods; D017483:Receptors, Vasopressin / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology / Q000378:metabolism*
chemical_list: C496871:CUL5 protein, human; D044842:Cullin Proteins; D019040:E-Selectin; D017483:Receptors, Vasopressin; D018799:Intercellular Adhesion Molecule-1