COL17A1 and autoimmune bullous skin disease: Indeed, this pathology is initiated by an inflammatory cascade that leads to the production of autoantibodies directed against key components of hemidesmosomes, known as bullous pemphigoid antigens (BPAGs) with a 230-kD (BPAG1 or BP-230) and a 180-kD (BPAG2 or BP-180) protein, and the secretion of specific enzymes, MMP-9 and elastase, both being essentially produced by neutrophils.