Pathologie acquise de la jonction dermo-épidermique

Abstract

The dermoepidermal junction (DEJ) is a supramolecular structure between the epidermis and the dermis. Its importance in the integrity of the skin is evidenced by the numerous inherited and acquired diseases which affect the DEJ and lead to subepidermal bullous disorders. Considerable progress has recently been made in the characterization of the molecules which constitute the basement membrane zone and of receptor/ligand interactions at the DEJ. Some molecules appear critical for the adhesion of the epidermis to the dermis since a genetic alteration in their structure or an autoimmune reaction directed to these molecules ultimately lead to dermal epidermal split and bullae formation. In respect to acquired bullous disorders, three molecules of the DEJ (bullous pemphigoid antigens (BP Ag 1 and BP Ag 2), collagen type VII and epiligrin/niceine) have been shown to be antigenic and are the targets of patients autoantibodies in three distinct diseases affecting the DEJ, namely bullous pemphigoid, epidermolysis bullosa acquisita and cicatricial pemphigoid. The better understanding in the molecular basis of acquired blistering skin diseases has already allowed the improvement of the diagnostic procedures and new insights in the nosology of this group of dermatoses.