Epidermal autonomous VEGFA/Flt1/Nrp1 functions mediate psoriasis-like disease.

Abstract

Psoriasis is a common chronic skin disorder characterized by keratinocyte hyperproliferation with altered differentiation accompanied by inflammation and increased angiogenesis. It remains unclear whether the first events that initiate psoriasis development occur in keratinocytes or inflammatory cells. Here, using different psoriasis mouse models, we showed that conditional deletion of <i>Flt1</i> or <i>Nrp1</i> in epidermal cells inhibited psoriasis mediated by <i>Vegfa</i> overexpression or <i>c-Jun/JunB</i> deletion. Administration of anti-Nrp1 antibody reverted the psoriasis phenotype. Using transcriptional and chromatin profiling of epidermal cells following <i>Vegfa</i> overexpression together with <i>Flt1</i> or <i>Nrp1</i> deletion, we identified the gene regulatory network regulated by <i>Vegfa</i>/<i>Nrp1</i>/<i>Flt1</i> during psoriasis development and uncovered a key role of Fosl1 in regulating the chromatin remodeling mediated by <i>Vegfa</i> overexpression in keratinocytes. In conclusion, our study identifies an epidermal autonomous function of Vegfa/Nrp1/Flt1 that mediates psoriatic-like disease and demonstrates the clinical relevance of blocking Vegfa/Nrp1/Flt1 axis in psoriasis.