Clinical Significance of Decreased TIPE2 Expression in Peripheral Blood Mononuclear Cells of Patients with Psoriasis Vulgaris

Psoriasis is an immune system disorder induced by the interaction of the polygenic background and environmental factors. Tumor necrosis factor-α (TNF-α)-induced protein 8-like 2 (TNFAIP8L2, TIPE2), a regulator of immunity, is differentially expressed in tumors, inflammation, and autoimmune diseases. However, to our knowledge, no study has evaluated TIPE2 expression in patients with psoriasis vulgaris. The present case-control study aimed to determine the expression levels of TIPE2 mRNA in the peripheral blood mononuclear cells (PBMCs) of patients with psoriasis vulgaris and analyze the correlation between TIPE2 and other inflammatory cytokine variations in the pathogenesis of psoriasis vulgaris. Thirty-three patients with psoriasis vulgaris and thirty-one healthy volunteers were enrolled from October 2021 to March 2022. The mRNA expression levels of TIPE2, RELA (NF-κb p65), TNF-α, IL-10, IL-6, and IL-1β in PBMCs were determined using qPCR. The severity of psoriasis vulgaris was determined according to the Psoriasis Area and Severity Index (PASI) scores. TIPE2 mRNA expression significantly decreased, while the expression of RELA, TNF-α, IL-10, IL-6, and IL-1β increased in patients with psoriasis vulgaris compared with that in the healthy control group. In addition, the expression levels of TIPE2, RELA, TNF-α, and IL-1β positively correlated with the PASI score. TIPE2 mRNA expression negatively correlated with IL-6 and positively correlated with TNF-α. Moreover, TIPE2 mRNA expression was higher in the active stage than that in the stationary stage. Notably, TNF-α expression levels were higher in patients with psoriasis vulgaris combined with a history of respiratory infection. TIPE2 may contribute to the pathogenesis of psoriasis and be a potential biomarker of psoriasis vulgaris.