Fig. 4
Epidermal infections caused by S. epidermidis and S. aureus. A S. epidermidis (102 and 104 CFU input) caused epidermal infections within 96 h of culture, visualized with H&E staining that revealed the structural damage and loss of granular layer compared to the control HEE (PBS). B Immunostainings of the AMPs SKALP/elafin and hBD2 showed induction of protein expression in case of an epidermal infection. C H&E staining of HEE colonized with the S. aureus clinical isolate SA-DUS-011 (104 CFU input) for 96 h compared to the control HEE (PBS). D HEEs inoculated with SA-DUS-011, harvested at different time points of infection and stained for the AMPs SKALP/elafin and hBD2. All HEEs had multiple visible large yellow colonies on top of the stratum corneum. Only the culture medium of the first HEE was not infected yet, analyzed with a blood agar plate and o/n incubation at 37 °C. Scale bar = 100 µm