title: Skin-homing T lymphocytes: detection of cutaneous lymphocyte-associated antigen (CLA) by HECA-452 in normal human skin.
abstract: The immigration of circulating T cells into specific tissues is directed by the interaction between adhesion molecules on lymphocyte subpopulations and their ligands on vascular endothelium. Of these, endothelial leucocyte adhesion molecule (ELAM-1), weakly expressed in normal human skin (NHS), seems to be the counter-structure for cutaneous lymphocyte-associated antigen (CLA). CLA is a 200 kDa cell-surface glycoprotein of which the sugar moieties sialyl Le(a) and sialyl Le(x) are the possible epitopes recognized by the monoclonal antibody HECA-452. HECA-452 was originally described as a marker for lymphoid organ high endothelial cells, but 16% of peripheral-blood-derived T cells react with this antibody. We studied the expression of CLA on the cellular constituents of the skin immune system (SIS). By applying immunohistochemical double staining, 41% of CD3+ T cells, 44% of CD4+ T cells and 31% of CD8+ T cells were found to express CLA. Keratinocytes, CD1a+ Langerhans cells (LC) and endothelial cells did not express HECA-452 in significant numbers in NHS. Monocytes were found to express HECA-452 in 14% of CD68+ cells. CLA expression was present on a relatively low percentage of T cells and subsets localized distant from NHS vessels, suggesting loss of the molecule during further migration after transendothelial passage. However, intraepidermal T cells expressed CLA in similar percentages to T cells localized directly perivascularly. Our findings support the notion that CLA expression by T cells is associated with their homing into cutaneous structures.
authors.affiliation: Department of Dermatology A0-235, University of Amsterdam, The Netherlands.
authors.forename: J D
authors.initials: JD
authors.lastname: Bos
authors.forename: O J
authors.initials: OJ
authors.lastname: de Boer
authors.forename: E
authors.initials: E
authors.lastname: Tibosch
authors.forename: P K
authors.initials: PK
authors.lastname: Das
authors.forename: S T
authors.initials: ST
authors.lastname: Pals
mesh_terms: D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D016201:Receptors, Lymphocyte Homing / Q000378:metabolism*; D012016:Reference Values; D012867:Skin / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D016201:Receptors, Lymphocyte Homing