Anthropophilic and zoophilic dermatophytes express specific genes when infecting reconstructed human epidermis

Dermatophytoses are superficial fungal infections of the host keratinized structures. While anthropophilic dermatophytes generally cause mildly inflammatory lesions only in humans, zoophilic species are responsible for more severe lesions. Despite the increasing incidence of dermatophytosis worldwide, and the emergence of strains resistant to available antifungals, there is still a lack of information about the virulence mechanisms and the factors determining host-specificity of dermatophytes species. Here, we used a previously developed model based on reconstructed human epidermis (RHE) to compare the development of infection between the anthropophilic Trichophyton rubrum and the zoophilic Trichophyton benhamiae. By optimizing a method for the recovery of both human and fungal RNA from infected RHE, we were able to investigate the expression of host inflammatory factors and fungal genes, including subtilisins as potential virulence factors. By this means, we showed that dermatophytes deployed the same processes during infection in RHE as those observed during in vivo infection, validating the infection model in RHE as a valuable tool to study pathogenesis of dermatophytoses. Furthermore, we identified some robust fungal markers of infection, and highlighted different mechanisms deployed by zoophilic or anthropophilic dermatophyte species.