Linear IgA bullous dermatosis is characterized by IgA autoantibodies reactive with LAD-1 and LABD97, truncated forms of BP180 (type XVII collagen), but not with full-length BP180.Toyonaga et al. determined that cleavage within both the C-terminal region and NC16A domain plays a role in exposure of neoepitopes on the 15th collagenous domain of BP180.
For immunolabeling, we used two recently developed monoclonal antibodies to LAD-1 whose epitopes were ultrastructurally localized in the lamina lucida between NC16A and carboxyterminal domains of BPAG2, as well as autoantibodies against LAD-1 from the sera of two patients with linear IgA dermatosis.
The anchoring filament protein LAD-1 has been recently identified as the target of autoantibodies in the acquired blistering disorder linear IgA bullous dermatosis.