A talin-dependent LFA-1 focal zone is formed by rapidly migrating T lymphocytes.
Cells such as fibroblasts and endothelial cells migrate through the coordinated responses of discrete integrin-containing focal adhesions and complexes. In contrast, little is known about the organization of integrins on the highly motile T lymphocyte. We have investigated the distribution, activity, and cytoskeletal linkage of the integrin lymphocyte function associated antigen-1 (LFA-1) on human T lymphocytes migrating on endothelial cells and on ligand intercellular adhesion molecule-1 (ICAM-1). The pattern of total LFA-1 varies from low expression in the lamellipodia to high expression in the uropod. However, high affinity, clustered LFA-1 is restricted to a mid-cell zone that remains stable over time and over a range of ICAM-1 densities. Talin is essential for the stability and formation of the LFA-1 zone. Disruption of the talin-integrin link leads to loss of zone integrity and a substantial decrease in speed of migration on ICAM-1. This adhesive structure, which differs from the previously described integrin-containing attachments displayed by many other cell types, we have termed the "focal zone."
Leukocyte Adhesion Laboratory, Cancer Research UK London Research Institute, London WC2A 3PX, England, UK.
Andrew
A
Smith
Yolanda R
YR
Carrasco
Paula
P
Stanley
Nelly
N
Kieffer
Facundo D
FD
Batista
Nancy
N
Hogg
D002448:Cell Adhesion / Q000502:physiology; D002450:Cell Communication / Q000276:immunology; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D002478:Cells, Cultured; D002634:Chemotaxis, Leukocyte / Q000502:physiology*; D022001:Focal Adhesions / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D016023:Integrins / Q000378:metabolism; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D016169:Lymphocyte Function-Associated Antigen-1 / Q000378:metabolism*; D011554:Pseudopodia / Q000276:immunology / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D016608:Talin / Q000378:metabolism*; D013997:Time Factors
D016023:Integrins; D016169:Lymphocyte Function-Associated Antigen-1; D016608:Talin; D018799:Intercellular Adhesion Molecule-1