Fogo selvagem, or endemic pemphigus foliaceus, is an organ-specific disease, where IgG autoantibodies, especially from the IgG4 subclass are directed against the ectodomains of desmoglein 1, culminating in acantholysis. Genetic and environmental influences modulate this specific autoimmune response; individuals with a determined sequence of alleles (LLEQRRAA) in the positions 67-74 of the third hypervariable region of the HLA-DRB1, or those exposed to hematophagous insects, especially Simulium nigrimanum, are more susceptible to develop the disease. A possible explanation for the development of the autoimmune process would be antigenic mimicry, initiated by environmental stimuli in those genetically predisposed individuals.
Autoimmunity; Fluorescent antibody technique; Epitope Mapping; Pemphigus
