title: The frequency of CLA+ CD8+ T cells in the blood of psoriasis patients correlates closely with the severity of their disease.
abstract: Psoriasis is thought to be a T cell-mediated skin disease and the cutaneous lymphocyte antigen (CLA) is an important skin homing epitope for T cells. We have studied the relationship between disease severity (PASI) and phenotypic analysis of T cells in the blood of 36 patients with psoriasis focusing on the expression of CLA, VLA-4 and CD25 on CD4+ and CD8+ T cells. The patients had a higher frequency of circulating CLA+ CD8+ cells than healthy controls. Furthermore, a much stronger correlation was observed between PASI and the frequency of CLA+ CD8+ than CLA+ CD4+ T cells. The frequency of CLA+D8+ T cells correlated more strongly with redness, thickness and scaling of the skin lesions than the total affected body surface area. In contrast to CLA the T cell expression of VLA-4 did not demonstrate any such correlation. Finally, the expression of the activation marker CD25 on CD8+ T cells showed a strong correlation with disease severity in patients with moderate to severe psoriasis (PASI > 10) but such correlation was not observed for CD4+ T cells. These findings support the notion that circulating CLA+ CD8+ T cells may play an important role in the pathogenesis of psoriasis.
authors.affiliation: Department of Immunology, Landspítali University Hospital, Reykjavík, Iceland.
authors.forename: H
authors.initials: H
authors.lastname: Sigmundsdóttir
authors.forename: J E
authors.initials: JE
authors.lastname: Gudjónsson
authors.forename: I
authors.initials: I
authors.lastname: Jónsdóttir
authors.forename: B R
authors.initials: BR
authors.lastname: Lúdvíksson
authors.forename: H
authors.initials: H
authors.lastname: Valdimarsson
mesh_terms: D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D016022:Case-Control Studies; D006801:Humans; D008562:Membrane Glycoproteins / Q000378:metabolism*; D011565:Psoriasis / Q000209:etiology / Q000276:immunology* / Q000473:pathology; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; C063419:CTAGE1 protein, human; D008562:Membrane Glycoproteins; D015375:Receptors, Interleukin-2