Linear IgA bullous dermatosis of adults and children: an immunoelectron microscopic study.

The ultrastructural localization of the IgA deposits in the skin of 15 patients with linear IgA bullous dermatosis of adults (LAD), 13 with chronic bullous dermatosis of childhood (CBDC) and three with childhood cicatricial pemphigoid (CCP) were studied. The site of the antigen was determined using sera from two LAD, 13 CBDC and two CCP patients. In all 31 patients the IgA was located predominantly below the lamina lucida (sublamina densa). Similarly, the indirect immunoelectron microscopic studies demonstrated the antigen to be present at the same site, below the lamina densa. This suggests that in linear IgA bullous dermatosis the antibody reacts with the antigen in the sublamina densa region of the basement membrane zone.