Skin blistering disorders result from damaged proteins involved in the dermal-epidermal adhesion. The damage is either caused by genetically induced defects or by autoantibodies targeting those proteins. In hereditary epidermolysis bullosa (EB) skin blistering is pathogenetically linked to genetic deficiency of distinct proteins of the epidermis or the dermal-epidermal junction, but circulating autoantibodies against these proteins have also been identified in EB patients. So far, the pathogenetic role of these autoantibodies is unclear, as they do not bind the respective skin structures, as shown by negative indirect immunofluorescence (IIF). In this project, we investigated sera of 258 EB patients by ELISA and found in 22 % of the patients autoantibodies against the bullous pemphigoid antigen BP180. Among those patients, we identified six (2.33 %) with clinical features of an autoimmune bullous disorder (AIBD) and positive IIF on human split skin. In the literature, we found four more cases of EB patients developing disease-aggravating AIBD. Co-existence of AIBD in 2.33% of the patients in our large EB cohort, compared to the prevalence of 0.05% in the general population and AIBD-onset at a very young age suggest that EB patients have a predisposition for the development of AIBD. Our work highlights that EB patients with increased itch or blister formation should be examined for additional AIBD and IIF is necessary to confirm pathogenicity of detected autoantibodies.

ESDR065 - Evaluating pathogenicity of skin autoantibodies in hereditary epidermolysis bullosa hints towards predisposition of autoimmunity

The scientific meeting of the European Society for Dermatological Research (ESDR) is held yearly, usually in September. With an international attendance of more than 1000 skin scientists from around the globe, the four-day event includes short oral presentations from peer-reviewed abstracts, keynote lectures from international experts, sponsored symposia, satellite programs, educational events as well as an important focus on posters, networking and building collaborations amongst scientists. For more information about this year’s meeting visit our website.