CD25(+)CD8(+), CLA(+)CD4(+), CD11a(+) CD4(+), and CD11a(+) CD8(+) T cell counts are elevated in the blood of Brazilian patients with chronic plaque psoriasis.

Psoriasis is a recurrent, chronic inflammatory disorder that mainly affects the skin and joints1. In view of the scarcity of studies on peripheral lymphocyte subpopulations in Brazilian psoriasis patients, we performed cytofluorometric analysis of peripheral blood mononuclear cells (PBMC) in psoriatic patients and healthy controls in order to characterize the lymphocyte subpopulations and certain molecules involved in cell activation and migration. The study was approved by the Ethics Committee of Escola de Medicina e Cirurgia (UNIRIO, MEC, Brazil) and all patients signed an informed consent. Twenty-five individuals were recruited from the Dermatology Department of HUGG/UNIRIO/MEC-Brazil. Seventeen had chronic plaque psoriasis and there were 8 healthy controls. None of the psoriasis patients was receiving systemic treatment. The physician’s global assessment score2—4 was 4 in 6 cases, 5 in 6 cases, and 6 in 5 cases. A 20-ml blood sample was drawn from each patient and PBMCs were separated using the Ficoll-Hypaque gradient (Sigma Chemical Co, St.Louis, USA). Five microliters of each monoclonal antibody—–anti-CD3, anti-CD4, anti-CD8, antiCD11a (Immunotech, Beckman Coulter, France), anti-CD25, anti-CD69, and anti-CLA (BD Biosciences, California, USA)— –were added according to the combinations listed in the table 1. Laboratory procedures were performed according to the manufacturer’s instructions5. The nonparametric MannWhitney and Kruskal-Wallis tests were used for the statistical analysis, which was performed using GraphPad Prism version 4.00 for Windows (GraphPad Software, San Diego, California, USA). Analysis of the lymphocyte subpopulations (CD3+ or total T cells, CD4+ or helper T cells, and CD8+ or cytotoxic T cells) revealed no significant differences between patients with psoriasis and healthy controls. The relative percentages of each lymphocyte subpopulation in patients and controls are shown in Figure 1. Lymphocyte activation was