Desmoglein 3 is a protein that is encoded by the DSG3 gene on Chromosome 18. Desmoglein 3 is a calcium-binding transmembrane glycoprotein component ofdesmosomes in vertebrate epithelial cells. Currently, four desmoglein subfamily members have been identified and all are members of the cadherin cell adhesion molecule superfamily. This protein has been identified as the autoantigen of the autoimmune skin blistering disease pemphigus vulgaris.

Desmoglein 3 has been cited as a superior marker for Lung Squamous Cell Carcinomas, and helps distinguish lung squamous cell carcinoma cases from lung adenocarcinoma. Studies have also shown that a panel consisiting of Desmoglein-3 utilized with Napsin A can be a useful Immunohistochemical marker for differentiation of lung squamous cell carcinoma and adenocarcinoma from other subtypes. Lung cases that are typically positive for Desmoglein 3 tend to have a poor clinical outcome.