COL17A1 and autoimmune bullous skin disease: These junctional complexes are formed by at least six different types of proteins: laminin-332 (laminin-5), the integrin  α6β4, the bullous pemphigoid antigens 180 (BP180, BPAG2, or type XVII collagen) and 230 (BP230 or BPAG1-e), CD151, and plectin [3–5].