antiDsg3

Anti-desmoglein-3 (anti-Dsg3) antibodies are autoantibodies directed against desmoglein-3, a cadherin-like cell adhesion protein found in desmosomes of stratified squamous epithelia, including mucous membranes. In pemphigus vulgaris, anti-Dsg3 antibodies disrupt keratinocyte adhesion, leading to acantholysis and the formation of flaccid blisters and erosions, often with mucosal involvement. The presence of anti-Dsg3 antibodies, especially when combined with anti-Dsg1 antibodies, underpins the mucocutaneous form of the disease, whereas anti-Dsg3 antibodies alone are commonly associated with mucosal-dominant disease.

Desmoglein-3 is more highly expressed in the lower epidermis and in mucosal tissues; anti-Dsg3 antibodies interfere with its adhesive function, contributing to loss of cell-cell cohesion. Detection of anti-Dsg3 antibodies is typically performed by enzyme-linked immunosorbent assay (ELISA) using recombinant Dsg3 antigen, and by indirect immunofluorescence, which reveals intercellular staining in epidermal keratinocytes. Antibody titers can correlate with disease activity in many patients and are useful for diagnosis and monitoring, though they do not always track perfectly with clinical severity.

Clinical management of anti-Dsg3–positive disease follows standards for pemphigus vulgaris, including systemic corticosteroids plus steroid-sparing immunosuppressants or biologics such as rituximab. Treatment aims to reduce antibody production and restore epidermal adhesion, with serial measurements of anti-Dsg3 aiding in monitoring response and relapse risk.