Psoriasis is a multifactorial immune-mediated disease. The highly effective and eligible treatment for psoriasis is limited, for its specific pathogenesis is incompletely elucidated. Skin microbiota is a research hotspot in the pathogenesis of immune-mediated inflammatory skin diseases nowadays, and it may have significant involvement in the provocation or exacerbation of psoriasis with broadly applicable prospects. It is postulated that skin microbiota alternation may interplay with innate immunity such as antimicrobial peptides and Toll-like receptors to stimulate T-cell populations, resulting in immune cascade responses and ultimately psoriasis. Achieving a thorough understanding of its underlying pathogenesis is crucial. Herein, we discuss the potential immunopathogenesis of psoriasis from the aspect of skin microbiota in an attempt to yield insights for novel therapeutic and preventive modalities for psoriasis.

Real‐life data on guselkumab in psoriasis are limited and not available in China hitherto. This study aimed to evaluate the short‐term effectiveness and safety of guselkumab in patients with psoriasis under Chinese real‐life conditions and to explore the effect of guselkumab on CD4+CD25+Foxp3+ regulatory T cells (Tregs). A Chinese prospective and real‐life study involving patients with psoriasis in Dermatology Hospital of Southern Medical University, Guangzhou, China from April to September 2020 was conducted. A total of 45 patients with psoriasis were finally enrolled in the study. Psoriasis Area Severity Index (PASI) 90 and 100 responses at week 16 were achieved by 88.6% and 45.5% of patients, respectively. The analysis of PASI response in different subgroups showed no statistically significant difference. Univariate logistic regression analysis revealed that at week 16, none of the variables were associated with decreasing PASI 90 response, whereas age at onset of disease was a predictor of PASI 100 response. Dynamic detection of CD4+CD25+Foxp3+ Tregs frequency from peripheral blood suggested a stable maintained trend in terms of guselkumab treatment duration. No severe adverse events occurred during the follow‐up period. This study confirmed the short‐term effectiveness and safety of guselkumab, as well as its good tolerance against psoriasis, in the Chinese population. Guselkumab treatment maintains levels of Tregs in patients with psoriasis.

Background. Psoriasis is a chronic immune-mediated skin disease requiring long-term management. However, for various reasons such as financial issues, treatment cessation is common among psoriasis patients who have achieved clinical remission. Currently, only few studies have assessed the time to relapse after guselkumab withdrawal in the real-world setting. Objective. The study aimed at assessing the time to relapse after remission following guselkumab discontinuation in patients with moderate-to-severe plaque psoriasis in the real-world setting. Materials and Methods. Eligible adult moderate-to-severe plaque psoriasis patients received at least 2 doses of administration of guselkumab treatment between March 2020 and March 2022 were enrolled. The study included patients who achieved PASI < 3 at week 12. Relapse was defined as restart of systemic therapy upon guselkumab withdrawal. Time to relapse was defined as the time interval between the last guselkumab administration and restart of systemic therapy. Results. Totally, 76 patients were enrolled. Relapse was found in 60.5% of patients, with a median PASI score at relapse of 4.6 (IQR: 1.6, 8.4) and median time to relapse was 201 (IQR: 159, 314) days. The proportion of patients with comorbidities significantly differed between the relapse and nonrelapse groups at baseline ( P < 0.05 ). Compared with patients with PASI < 3, those with PASI ≥ 3 at relapse had longer time to relapse ( P < 0.001 ). Conclusions. Guselkumab provides durable maintenance of response after discontinuation of therapy in the real-world setting. Higher PASI score at relapse was associated with longer time to relapse. This trial is registered with Chinese Clinical Trial Registry: ChiCTR2000041398.