Identification of autoantibodies contributing to the break of immunotolerance in immunization induced MMP mouse model

Mucosal pemphigoid (MMP) is one of the bladder-forming autoimmune diseases with predominant involvement of the mucous membranes. Autoantibodies target components of the basal membrane. In particular, it shows an activity directed against the protein laminin-332 which is associated with an increased risk of developing malignant tumours.Patients with MMP have been shown to have an HLA polymorphism whose influence on the development of the disease is still unclear. Tu study this mechanism, samples from the established MMP mouse model designed for anti-laminin 332 MMP are used. This shows great similarity to characteristics of human disease expression.Samples of this mouse model are used to determine the genetic impact on disease development, as well as the influence of antibody subclasses. To a certain extent, conclusions can be drawn about the underlying pathophysiology, in particular the development of antibodies against different epitopes or proteins.To achieve these objectives, samples in the form of serums and biopsies are collected from mice with three different genetic backgrounds. These were immunized with two different fragments of the murine laminin-332 alpha chain.Epitopes and proteins that can act as auto antigens in MMP are analyzed with the help of western blot and immunoprecipitation.In order to investigate the question of epitope spreading, nearby structural proteins (mCOL7, mCOL17) are included in the study. The autoantibodies are analyzed by ELISA regarding their subclasses. This examination is continued in the form of indirect and direct immunofluorescence.