For example, when AA target proteins within superficially expressed desmosomes (i.e., DSG1 and/or desmocollin [DSC]-1) restricted to the granular and/or upper spinous layers of the epidermis, a form of superficial pemphigus known as pemphigus foliaceus (PF) develops [5] that only affects the skin, and not the mucosae. Here, DSG1 is linked to pemphigus foliaceus.