A. benhamiae ΔacuE mutants induce symptoms of inflammatory dermatophytosis comparable to those of the wild type. Shown is the development of skin lesions and skin fungal colonization in guinea pigs 14 days postinfection with A. benhamiae strain AbenACUEM1A (B, E, and H) and AbenACUEM1B (C, F, and I) or the control parental strain Lau2354-2 (A, D, and G). (A to C) Macroscopically visible inflammatory skin lesions consisting of erythema, alopecia, moderate scaling, crusting, and severe excoriations due to pruritus are similar between those induced by the control parental strain Lau2354-2 (A) and the mutant strains AbenACUEM1A (B) and AbenACUEM1B (C). (D to F) PAS-stained cross-section microscopy of a scaly and crusty infected area showing similar levels of fungal colonization (arrows) of the keratinized superficial epidermis (epidermal horny layer [EHL]) in flanks infected with the control parental strain Lau2354-2 (D) and the mutant strains AbenACUEM1A (E) and AbenACUEM1B (F). (G to I) PAS-stained cross-section microscopy of an infundibular-isthmal hair follicle (IIHF) showing similar levels of fungal colonization (arrows) of hair keratin in flanks infected with the control parental strain Lau2354-2 (G) and the mutant strains AbenACUEM1A (H) and AbenACUEM1B (I).