Psoriasis: comparison of immunological markers in patients with acute and remission phase.

The immune system involvement in psoriasis has been documented by the presence of activated T-cells both in peripheral blood and in psoriatic skin lesions and by the intervention of cytokines in the inflammatory process. On this basis, we have undertaken a study in order to examine, in addition to activation markers such as CD25 and CD54 (ICAM-1) on peripheral blood mononuclear cells (PBMNCs) surface, serum levels of soluble interleukin (IL)-2 receptor (sIL-2R), soluble ICAM-1 (sICAM-1), soluble CD4 (sCD4), soluble CD8 (sCD8), beta 2-microglobulin and fibronectin (FN) in psoriatic patients analyzed both in acute and remission phase obtained by topical therapy alone. Our results show that PBMNCs expressing IL-2 receptor (CD25) were increased both in percentage and absolute number in respect to controls, and were not modified after remission. On the contrary, the significantly higher number of CD54+ lymphocytes evaluated in acute psoriasis, showed a reduction during the remission phase, even if the values persisted higher than controls. Serum levels of sIL-2R, sICAM-1, sCD4, sCD8 and beta 2-microglobulin were significantly higher than controls both in acute and remission phase; only FN levels were found to be lower, in patients evaluated both in acute psoriasis and after therapy, in respect to normal donors. On the whole, these results seem to indicate the persistence of both cellular and soluble activation markers even in psoriasis remission phase; in this light, we can suppose that topical therapy alone is not able to efficiently down-regulate activation mechanisms involved in the pathogenesis of the disease.