Morphological Characterization of Local Defence System in the Skin of Psoriasis Patients. Summary of the Doctoral Thesis

Abstract

Psoriasis is a chronic inflammatory skin disease that affects 1–3% of the European population. Psoriasis is characterized by substantial biochemical, immunological, genetic and vascular changes. Significant alternations affect the epidermal growth and differentiation processes. At the same time, psoriasis is associated with higher metabolic syndrome and diabetes development possibilities, as well as increased cardiovascular risk. In skin of psoriasis patients increased amount of microorganisms has been observed, but these patients rarely develop secondary bacterial skin infections, which is linked to the presence of the natural antimicrobial peptides. The aim of this research was a morphological study of local skin defense system in psoriasis patients with various progress of the disease in ontogenetic aspect. The study included 40 patients with Psoriasis vulgaris with untreated skin inflammation and 10 control patients without any history of inflammatory skin diseases and existing visual changes on the skin. Skin tissue samples were obtained from all patients. Immunoreactive cells and the relative quantity of nerve fibers containing human beta defensin-2 (hBD-2), protein gene product 9.5 (PGP 9.5), calcitonin gene-related peptide (CGRP), substance P, tumor necrosis factor alpha (TNF-α), interleukin-1 alpha (IL-1α), interleukin-6 (IL-6), interleukin-8 (IL-8), matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinase-2 (TIMP-2) and tissue inhibitor of metalloproteinase-4 (TIMP-4) were examined and analyzed by the immunohistochemistry method. The presence of apoptosis and distribution of apoptotic cells was determined by the TUNEL method. Statistically significant difference between patients with psoriasis and control patients we found for hBD-2, PGP 9.5, substance P factors and apoptotic cells in epidermis and dermis, and for CGRP, TIMP-2 and TIMP-4 factors in epidermis. In the skin of psoriasis patients with different disease duration and progress activation of skin antimicrobial peptides, specific neuropeptides-containing innervation (sensory), inflammatory cytokines, degeneration enzymes and programmed cell death is essential, suggesting their involvement in the morphopathogenesis of psoriasis. At the same time findings of these factors statistically significantly do not correlate with patient age, sex, disease duration and season, excluding these parameters from involvement in the pathogenesis of the disease. In the prognostic diagnostic algorithm of psoriasis patient the detection of such molecular markers as hBD-2, CGRP, IL-6, IL-8, MMP-2 and TIMP-4 should be included.