Correlation Between IL-33 And Its Receptor ST2 And Psoriasis Vulgaris

Background Psoriasis is a common chronic inflammatory immune-related skin disease. There were four types in clinical practice:erythroderma, arthropathica, pustulosa, and psoriasis vulgaris. Psoriasis vulgaris is a very important type of psoriasis, which accounted for more than 94.6% of all patients with psoriasis. At present, the pathogenesis of psoriasis have not been fully illustrated, but the existence of abnormal immune in skin lesion has been widely recognized. Interleukin (interleukin, IL)-33 is newly found a kind of IL-1 cytokine superfamily member. Constitutive expression of IL-33 is found in a variety of human tissue cells. There is a close link between IL-33 and a variety of diseases such as cardiovascular disease, autoimmune diseases, inflammatory bowel disease, inflammation and tumors, etc. ST2, the receptor of IL-33, is mainly expressed in the Th2 cells, mast cells, macrophages, dendritic cells, NK cells and natural killer T cells and other immune cells surface. So far, the relationship between the expression of IL-33 and ST2 and psoriasis vulgaris has not been fully elucidated.Objective Study of the expression of interleukin 33 and its receptor ST2 in psoriasis vulgaris (PV) lesions, and to explore their role in the pathogenesis of psoriasis.Methods 30 patients with psoriasis vulgaris and 15 healthy controls were selected as research object. The expression levels of IL-33 and the ST2 were detected using Envision immunohistochemistry and indirect immunofluorescence method.Result Compared with the healthy control group skin tissue, the expression levels of ST2 and IL-33 were significantly increased from the base layer of epidermal cells to granular layer in the skin lesion in patients with psoriasis vulgaris. It was also highly expressed in the dermis blood vessels, inflammatory cells, hair follicles, sebaceous glands. Of the 30 skin lesion tissue in psoriasis vulgaris, there was 12 and 11 cases strong positive expression of IL-33 and ST2. The positive expression rate of IL-33 was 90% and 46.67%; and that of ST2 was 83.33% and 53.33% respectively in the psoriatic group and healthy control group, and there were significant differences(P<0.05).Conclusion IL-33 and its receptor ST2 increased expression in psoriatic skin lesions, and a positive correlation with the degree of inflammation, as in patients with psoriasis area and severity of lesions indicators.