What is Desmoglein III Antibody?

The Desmoglein III antibody test or DSG III antibody test is performed to screen for and diagnose the autoimmune disease Pemphigus. Pemphigus is an autoimmune disease where antibodies are produced against Desmoglein, which forms a type of glue that joins the epidermal cells or skin cells together. Antibodies target and destroy desmoglein, causing pemphigus.

Why is Desmoglein III Antibody done?

1. To diagnose the causes of blisters or lesions on the skin surface and the mucosal membranes of the mouth and genitals
2. To assess painful blisters that start near the mouth
3. When crusting and peeling of skin at or near the blisters appears
4. To diagnose pemphigus

Clinical Information

Pemphigus includes a group of often fatal autoimmune blistering diseases characterized by intraepithelial lesions. Pemphigus vulgaris and its variants may present with oral or mucosal lesions alone or with mucosal plus skin lesions. Pemphigus foliaceous and variants present with skin lesions alone.

Indirect immunofluorescence (IIF) studies reveal that both forms of pemphigus are caused by autoantibodies to cell surface antigens of stratified epithelia or mucous membranes and skin. These antibodies bind to calcium-dependent adhesion molecules in cell surface desmosomes, notably desmoglein 1 (DSG1) in pemphigus foliaceus and desmoglein 3 (DSG3) and/or DSG1 in pemphigus vulgaris. Desmogleins are protein substances located in and on the surface of keratinocytes. These proteins have been shown to be a critical factor in cell-to-cell adhesion. Antibodies to desmogleins can result in loss of cell adhesion, the primary cause of blister formation in pemphigus.

The diagnosis of pemphigus depends on biopsy and serum studies that characterize lesions and detect the autoantibodies that cause them. Originally, the serum studies were performed by IIF using monkey esophagus and other tissue substrates. The identification of the reactive antigens as DSG1 and DSG3 has made it possible to develop highly specific and sensitive enzyme-linked immunosorbent assay methods.