Alteration of Th1 and Th17 Inflammatory Cytokines in the Skin Lesions after Psoriasis Treatment

Background: Psoriasis is a T cell-mediated disorder. Appropriate treatment of psoriasis can result in a plethora of dynamic changes in the T cells and their cytokine production. Studies on the expression of Thl and Thl7 inflammatory cytokines after various treatments have reported inconsistent results. Objective: This study aimed to investigate the changes in inflammatory cytokine expression in psoriasis skin lesions before and after psoriasis treatment. Methods: Five patients with plaque psoriasis were enrolled in the study. The tissue mRNA and protein levels of interleukin (IL)-12, IL-2, interferon (IFN)- γ, IL-23, IL-17A, and IL-22 in psoriatic skin lesions before and after psoriasis treatment were detected using real-time polymerase chain reaction and immunohistochemical staining, respectively. Results: The decrease in the psoriasis area and severity index was accompanied by a reduction in IL-12 and IL-23 mRNA levels and a concomitant reduction of IL-2 and IL-I7A protein levels in psoriasis skin lesions. Both mRNA and protein levels of IFN-γ in psoriatic skin lesions increased after treatment. Conclusion: The mRNA levels of tissue inflammatory cytokines (IL-12 and IL-23) and the protein levels of tissue inflammatory cytokines (IL-2 and IL-17A) significantly decreased after psoriasis treatment. The mRNA and protein levels of IFN-γ increased, even after psoriasis treatment.