antiDSG1

AntiDsg1, short for anti-desmoglein-1 antibodies, refers to autoantibodies directed against desmoglein-1, a cadherin protein that is a component of desmosomes and mediates cell–cell adhesion in the superficial epidermis. Desmoglein-1 is most abundant in the upper layers of the skin, and its disruption can lead to loss of keratinocyte adhesion and blister formation.

These autoantibodies are a serologic hallmark of pemphigus foliaceus, including its endemic form fogo selvagem, and may be present in other pemphigus subtypes to varying degrees. In pemphigus foliaceus, anti-Dsg1 antibodies target the superficial epidermis, producing superficial blisters and crusted erosions. In pemphigus vulgaris, anti-Dsg3 antibodies predominate, and anti-Dsg1 antibodies may occur in patients with mucocutaneous involvement.

Diagnosis combines clinical features with serologic testing. Indirect immunofluorescence and enzyme-linked immunosorbent assay (ELISA) using recombinant Dsg1 detect anti-Dsg1 IgG antibodies. Antibody titers often correlate with disease activity and are used to monitor response to therapy alongside testing for anti-Dsg3 when relevant.

Pathophysiology involves antibody-mediated disruption of desmosomal adhesion, leading to acantholysis in the epidermis. The circulating anti-Dsg1 pool is mostly IgG, commonly of the IgG4 subclass, and is considered pathogenic in disease models.

Treatment focuses on reducing autoantibody production and controlling inflammation, typically through immunosuppressive therapies and B-cell–targeted treatments as appropriate.