The skin is the largest organ of the body, it protects it from damage and hosts immune system cells. To function effectively as a barrier, the skin continually regenerates producing new cells to replace the old. If the regeneration process fails the skin may produce tumors. In addition, disruption to the immune barrier can lead to autoimmune or allergic skin diseases such as psoriasis or atopic dermatitis.
This mouse model has epidermis-specific Braf/Raf1 ablation, mediated by Cre expression in the basal epidermal layer and follicular keratinocytes using the Keratin 5 promoter. In normal conditions Braf and RAF1 operate independently to balance MAPK signalling. Removal of Braf and Raf1 in this model caused mice to develop an allergic disease similar to human atopic dermatitis, characterized by IgE responses (chemokines and Th2-type cytokines) with local and systemic inflammation.