Finding models for skin diseases: successes and failures

Hidradenitis suppurativa (HS) is a disfiguring and debilitating, relatively rare disease in humans. Reports of similar diseases in domestic animals are also very rare. A clinically similar disease was reported in dogs, particularly in Collies and Shelties, but this was later re‐evaluated and determined to be a form of vesicular cutaneous lupus erythematosus. The alternative term for HS, acne inversa, suggests forms of acne in domestic animals might provide an alternative approach to finding a model. Mice, unlike dogs and cats, do not generally develop acne. However, the icthyosis mutation (Lbr ic ) does develop bacterial infections within the infundibulum that may result in furunculosis. If combined with various immunodeficiencies, through the creation of double mutant mice, then this might provide a useful model. However, finding spontaneous or genetically engineered mouse models usually result in obtaining the best tools. The success obtained by developing or finding simple single gene mutation or complex polygenic disease models for pseudoxanthoma elasticum and alopecia areata, respectively, through support from their respective foundations, provide a road map on how such models can be found, defined, and provide unique tools to unravel the complex mechanisms of HS and, more importantly, provide preclinical tools for drug efficacy testing approaches.