Objective: The critical role of infiltrating T cells in the pathogenesis of psoriasis is now well established. In order to determine whether circulating T cells from patients with psoriasis were also involved in the disease process, the authors investigated the biological behavior as studied by chemotactic activity of T cells in patients with psoriasis.
Methods: A 48 microchemotaxis chamber was employed to determine T-cell chemotaxis activity. In addition, the expression of T cell activation markers such as HLA-DR and interleukin 2 receptor were analysed with fluorescence activated cell sorting technique and serum IL-8 level was measured with ELISA methods. Forty-five patients with psoriasis (23 patients with severe psoriasis and 22 with mild psoriasis) and 21 patients with atopic dermatitis were investigated. For comparison, T-lymphocytes from 20 healthy controls were tested equally.
Results: T-cell chemotactic responses were significantly decreased in patients with severe psoriasis and atopic dermatitis as compared to healthy controls. Increased expression of activation markers such as HLA-DR and interleukin 2 receptor were demonstrated in circulating T cells from psoriatic patients and atopic dermatitis patients in comparison to healthy controls. Serum IL-8 level was significantly increased in patients with psoriasis and atopic dermatitis.
Conclusions: Circulating T cells in patients with severe psoriasis show abnormal in vitro chemotactic response to IL-8. Furthermore, the in vivo activation state of T lymphocytes in these patients and increased level of serum IL-8 seemed to be associated to their decreased in vitro T-cell chemotactic responses.