PMID: 8596031Mar 1, 1996Paper

T cell adhesion to intercellular adhesion molecule-1 (ICAM-1) is controlled by cell spreading and the activation of integrin LFA-1

The Journal of Immunology : Official Journal of the American Association of Immunologists
M P StewartNancy Hogg

Abstract

Many leukocyte integrins require activation before they can adhere to their ligands. For example, stimulation of T cells enables the integrin LFA-1 to bind to ligand. This study compares two well known protocols for inducing T cell LFA-1 mediated adhesion to intercellular adhesion molecule-1 (ICAM)-1. We how that treatment with high concentrations of the divalent cation Mg2+ induces a high affinity state of LFA-1, which is reflected in the binding of soluble ICAM-1 and correlates with the expression of the epitope recognized by mAb 24. The second stimulation protocol with the phorbol ester phorbol-12,13-dibutyrate (PDBu) does not induce a high affinity state of LFA-1, and in this situation, adhesion is dependent on cell spreading and intracellular events involving protein kinase C, [Ca2+]i, and actin polymerization. These low affinity LFA-1 receptors are responsible for the initial contact with immobilized ligand because, unlike the Mg2+-stimulated receptors, adhesion is not blocked by soluble ICAM-1. Finally, we used a third method of inducing LFA-1-mediated adhesion by stimulation of T cells through the TCR/CD3 complex. This procedure, which is considered to be a more physiologic trigger for LFA-1 activation, resembles the ph...Continue Reading

Related Concepts

Related Feeds

Adhesion Molecules in Health and Disease

Cell adhesion molecules are a subset of cell adhesion proteins located on the cell surface involved in binding with other cells or with the extracellular matrix in the process called cell adhesion. In essence, cell adhesion molecules help cells stick to each other and to their surroundings. Cell adhesion is a crucial component in maintaining tissue structure and function. Discover the latest research on adhesion molecule and their role in health and disease here.