Pifu-xingbing zhenliaoxue zazhi (Feb 2023)
Imbalance of expression levels of IL-36γ and IL-38 is possibly associated with the severity of inflammation in psoriasis vulgaris
Abstract
Objective To investigate the roles of cytokines, IL-36γ and IL-38, in the inflammatory response in psoriasis vulgaris. Methods Both serum and peripheral blood mononuclear cells (PBMC) were collected from 29 patients with psoriasis vulgaris (PV) and 19 healthy controls. PV group was divided into mild to moderate group (n=14) and severe group (n=15) according to psoriasis area and severity index (PASI). In addition, serum and PBMC were collected from 12 PV patients before and after the treatment with IL-17A monoclonal antibody (IL-17A mAb). Serum levels of IL-36γ and IL-38 were measured using ELISA, and the relative expression levels of IL-36γ and IL-38 mRNA in PBMC were determined using RT-quantitative real-time PCR (RT-qPCR). Moreover, human immortalized keratinocytes (HaCaT) cocultured with IL-17A were sampled at different time points to measure expression levels of IL-36γ and IL-38 mRNA. Results Serum IL-36γ levels were significantly higher in patients with either mild to moderate or severe psoriasis than in healthy controls (t=12.27 and 16.45, respectively, P<0.001), but IL-38 levels were significantly lower in psoriatic patients than in healthy controls (t=5.83 and 7.61, respectively, P<0.001). In comparison to baseline levels, treatments of psoriasis with IL-17A mAb for 4 weeks markedly lowered serum levels of IL-36γ (t=3.24, P=0.004), while increasing IL-38 levels (t=3.36, P=0.001), along with similar changes in expression levels of IL-36γ and IL-38 mRNA in PBMC of psoriatic patients. Moreover, IL-17A increased the expression levels of IL-36γ mRNA, while decreasing expression levels of IL-38 in HaCaT cultures. Conclusions The expression levels of proinflammatory cytokine, IL-36γ, are significantly increased in peripheral blood of PV patients, while the expression levels of anti-inflammatory cytokine, IL-38, are significantly decreased. Treatments with IL-17A antibody reverse the expression levels of IL-36γ and IL-38 to some extent, suggesting an essential role of IL-36γ and IL-38 in chronic inflammation of psoriasis. IL-36γ and IL-38 could serve as serological markers for the assessment of the efficacy of biologics for psoriasis.
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