Biopsy-guided cytokine profiling in PsO

Results from a cross-sectional study examining biopsy-guided cytokine profiling across five psoriasis (PsO) subtypes were published in Clinics in Dermatology by Soto et al. Quantitative immunohistochemistry (IHC) analysis of interleukin (IL)-17A, IL-17F, IL-23p19, IL-36γ, and tumor necrosis factor-α (TNF-α) expression was performed on formalin-fixed, paraffin-embedded (FFPE) skin biopsies from 16 patients using digital pathology. The PsO subtypes included plaque (n = 5), guttate (n = 3), inverse (n = 3), generalized pustular (GPP; n = 3), and palmoplantar (n = 2). The objectives of this study were to characterize subtype-specific cytokine expression patterns, evaluate the feasibility of biopsy-guided profiling as a clinically accessible tool, and explore its potential contribution to precision biologic therapy in PsO. 

Key data: Distinct dermal cytokine profiles were observed across subtypes. Guttate PsO was characterized by elevated levels of IL-17A and IL-17F compared with IL-36γ and TNF-α (p < 0.05); similarly, inverse PsO showed modest enrichment of IL-17 cytokines compared with other markers. Analyses of palmoplantar PsO revealed significant increases in IL-17A relative to IL-36γ and TNF-α (p < 0.05), while other cytokine levels were more variable. Plaque PsO exhibited broad cytokine expression, with relative IL-17A predominance vs TNF-α and IL-36γ (p < 0.05–0.01), and prominent IL-17F and IL-23p19 expression. GPP demonstrated a distinct profile characterized by enrichment of IL-17F- and IL-36γ-positive cells vs all other subtypes (p < 0.0001–0.001). 

Key learning: These findings suggest that biopsy-guided cytokine profiling may help characterize subtype-specific inflammatory patterns in PsO. Prospective studies are needed to establish clinical utility and whether this approach can inform biologic treatment decisions.