Update on immunogenetics of Tunisian endemic pemphigus foliaceus.

Pemphigus foliaceus (PF) is an autoimmune blistering skin disease characterized by the presence of bullous skin lesions, the absence of mucous tissue involvement, and the production of auto-antibodies directed against a keratinocyte transmembrane protein localized in the desmosome and member of the cadherines, desmoglein 1. These pathogenic auto-antibodies are responsible for the intra-epidermal formation of blisters through the loss of keratinocyte adhesion, the so-called acantholysis process. The endemic form of PF observed in the south of Tunisia is characterized by a significantly higher incidence rate compared to the sporadic form in northern countries, occurrence mainly in young women and the absence of cases during childhood. Tunisian endemic PF is an ideal research model for the decryption of the puzzle of genetic and environmental factors and their interactions in the development of autoimmune diseases. In this review, we will summarize recent findings regarding the epidemiologic and immunologic features of Tunisian PF and its genetic and environmental factors.