title: Activated T cells acquire endothelial cell surface determinants during transendothelial migration.
abstract: Activated T cells acquire endothelial cell (EC) plasma membrane constituents during transendothelial migration. This was assessed using an in vitro model system in which human peripheral blood CD4+ T cells migrated through confluent monolayers of HUVEC. Flow cytometry of migrated CD4+ T cells demonstrated that activated, but not resting, T cells acquired a variety of endothelial surface determinants, including CD31, CD49d, CD54, CD61, and CD62E. The extracellular domains of these molecules were detected on migrated T cells with mAbs, including those directed to the ligand-binding regions. A number of approaches were employed to document that the acquisition of these molecules was uniquely accomplished by activated T cells and clearly involved transfer from both resting and TNF-alpha-activated EC. Acquisition of endothelial markers by activated T cells occurred as part of the transfer of membrane components, as migrating T cells acquired EC membranes prelabeled with the lipophilic dye, 3,3'-dihexadecyloxacarbocyanine perchlorate (DiOC-16), along with EC surface proteins. Thus, during transendothelial migration, activated T cells acquire endothelial membrane components, and as a result may deliver them to perivascular sites.
authors.affiliation: Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75235, USA.
authors.forename: R I
authors.initials: RI
authors.lastname: Brezinschek
authors.forename: N
authors.initials: N
authors.lastname: Oppenheimer-Marks
authors.forename: P E
authors.initials: PE
authors.lastname: Lipsky
mesh_terms: D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D017209:Apoptosis; D001483:Base Sequence; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000502:physiology*; D002462:Cell Membrane / Q000276:immunology; D002465:Cell Movement; D002478:Cells, Cultured; D017931:DNA Primers / Q000235:genetics; D019040:E-Selectin / Q000235:genetics / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000276:immunology*; D006801:Humans; D066298:In Vitro Techniques; D039421:Integrin alpha2; D039661:Integrin beta3; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D008213:Lymphocyte Activation; D008954:Models, Biological; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D010980:Platelet Membrane Glycoproteins / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction