Many inflammatory diseases begin with a relapsing-remitting phase that progressively worsens until the condition becomes entirely chronic. Relapses of disease activity (so-called flares) often occur in region that had previously been affected and are often triggered by withdrawal or tapering of anti-inflammatory therapy. Also pemphigoid diseases (PDs) exhibit a relapsing-remitting disease pattern and frequently flare upon modulation of therapy. Furthermore, PD lesions exhibit a scattered regional distribution, affecting certain skin areas more often while others like the face are mostly spared. The preferential affection of specific body parts although antibody deposition is more or less homogenously distributed over the skin on the whole body suggests an involvement of local cell populations facilitating inflammation at certain spots. Recently, resident mesenchymal cells have emerged to be major drivers of the inflammatory tissue response. Dermal fibroblasts (DFs) of the skin have only recently attracted more attention from the scientific community and have been shown to be importantly involved not only in fibrosis but also in vitiligo. The aim of project B10 is to understand the contribution of dermal fibroblasts to the pathogenesis of PDs.