To evaluate the efficacy of combined methotrexate and narrowband UVB phototherapy - 70 patients with moderate-to-severe plaque psoriasis who satisfy the inclusion criteria were divided into 2 equal groups matched for age, sex, and severity 10 - First testing (before treatment): + Experimental group: CD4, CD8, IL-2, IL-4, IL-6, IL-8, IL-10, IL-17, TNF-α, IFN -, AST, ALT, urea, creatinine, and CBC.