title: Expression of the cutaneous lymphocyte-associated antigen in circulating T cells in drug-allergic reactions.
abstract: BACKGROUND
  Mechanisms underlying the production of delayed cutaneous reactions to drugs are poorly characterized. The cutaneous lymphocyte-associated antigen (CLA) is a skin-homing T cell receptor that defines T lymphocytes associated with the cutaneous immune response. We studied the percentage and activation phenotype of circulating CLA+ T cells in drug allergic patients and healthy controls.
  
  
  METHODS
  PBMCs were isolated from heparinized venous blood by Ficoll density gradient. Lymphocytes were stained for flow cytometry with anti-CLA, anti-CD3 and anti-HLA-DR mAbs. Five-parameter analysis was performed on an Ortho Cytoron Absolute flow cytometer.
  
  
  RESULTS
  We found increased percentages of circulating CLA+ T cells in drug-allergic patients compared to controls. Moreover, CLA+ T cells from drug-allergic individuals expressed a higher percentage of the T cell activation marker HLA-DR.
  
  
  CONCLUSIONS
  These results suggest that CLA+ T cells may play a role in the pathology of delayed cutaneous reactions to drugs. Further studies are in progress to elucidate the role of skin-homing T cells in allergic reactions to drugs.
authors.affiliation: Internal Medicine Department, Carlos Haya Hospital, Malaga, Spain.
authors.forename: F J
authors.initials: FJ
authors.lastname: Gonzalez
authors.forename: M J
authors.initials: MJ
authors.lastname: Carvajal
authors.forename: L
authors.initials: L
authors.lastname: Leiva
authors.forename: C
authors.initials: C
authors.lastname: Juarez
authors.forename: M
authors.initials: M
authors.lastname: Blanca
authors.forename: L F
authors.initials: LF
authors.lastname: Santamaria
mesh_terms: D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; D004342:Drug Hypersensitivity / Q000276:immunology*; D006801:Humans; D008562:Membrane Glycoproteins / Q000032:analysis*; D016201:Receptors, Lymphocyte Homing / Q000032:analysis*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; C063419:CTAGE1 protein, human; D008562:Membrane Glycoproteins; D016201:Receptors, Lymphocyte Homing