AbstractObjectiveTo investigate the effects of secukinumab treatment for psoriasis on different functional cytokines and inflammatory mediators in patients’ serumMethodsEnzyme‐linked immunosorbent assay was used to detect interleukin (IL)‐1β and IL‐1RA associated with intrinsic immunity; IL‐6, IL‐18, and growth regulated oncogene alpha (GROα) associated with neutrophils; IL‐12, tumour necrosis factor (TNF)‐α, and interferon (IFN)‐γ associated with Th1; IL‐23, IL‐17A, and IL‐22 associated with Th17; Thymus activation regulated chemokine (TARC), IL‐13, and defensin beta 2 (DEFB2) associated with Th2; Vascular endothelial growth factor (VEGF)‐A and IL‐10 associated with angiogenesis; and IFN‐γ associated with sepsis in the peripheral blood of 12 patients with common psoriasis treated with secukinumab and 15 healthy controls. IL‐23, IL‐17A, IL‐22 associated with Th17; TARC, IL‐13, DEFB2 associated with Th2; VEGF‐A, IL‐10 associated with angiogenesis and procalcitonin (PCT) associated with sepsis. The differences in expression of the above cytokines before and after treatment and the correlation with psoriasis disease severity［Psoriasis Area Severity Index(PASI) score］, age, and disease duration were analyzed.ResultsThe mean PASI score of the enrolled patients with moderate to severe psoriasis was 21.6 ± 11.0 before treatment and decreased to below 1 after treatment. Serum IL‐6; IL‐18, GROα, IFN‐γ, TNF‐α, VEGF‐A, and IL‐17A were significantly higher than normal. And IL‐17A and IFN‐γ were positively correlated with disease duration and age, and IL‐18 was positively correlated with PASI score. The expression levels of IL‐6, GROα, VEGF‐A, IFN‐γ, TNF‐α, IL‐17A and IL‐23 were significantly lower after secukinumab treatment compared with those before treatment, but the expression levels of IFN‐γ, VEGF‐A, TARC, IL‐13, and DEFB2 were still significantly higher than those of normal subjects after treatmentConclusionssecukinumab clears skin lesions by antagonizing IL‐17A and simultaneously decreasing the expression levels of IL‐6, GRO α, VEGF‐A, IFN‐γ, TNF‐α, IL‐17A, and IL‐23.