Local IgG autoantibody profiles in hidradenitis suppurativa and their associations with disease features and anti-TNF therapy

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disorder marked by dysregulated TNF-α signaling and aberrant adaptive immune responses, yet the role of humoral autoimmunity in disease pathogenesis remains incompletely understood. Although autoantibodies have been reported in HS, their prevalence, specificity, and clinical relevance, particularly in relation to clinical features and biologic therapy, are not well defined. This study aimed to characterize lesional IgG autoantibody profiles in HS and evaluate their associations with clinical features, comorbidities, and biologic treatment status. Skin biopsy specimens from 20 patients with HS and 5 control subjects were analyzed for IgG autoantibodies, and findings were correlated with clinical features. Patients with HS demonstrated significantly elevated lesional IgG autoantibody levels, with greater abundance observed in chronic disease stages. Higher autoantibody levels were more prevalent among Black patients and correlated with disease severity (Hurley stage, hidradenitis suppurativa lesion, area, and severity index), lesion type (sinus tracts, scarring), comorbidities including asthma, acne, and diabetes, and clinical factors such as pain severity and smoking status. Samples from patients receiving adalimumab showed lower autoantibody levels, whereas no consistent pattern was observed with infliximab. These findings identify lesional IgG autoantibodies as a feature of HS and support a role for humoral autoimmunity in HS pathobiology, warranting longitudinal investigation.