Internalized by Skin Keratinocytes Evade Antibiotic Killing.

causes the majority of skin and soft tissue infections. Half of patients treated for primary skin infections suffer recurrences within 6 months despite appropriate antibiotic sensitivities and infection control measures. We investigated whether internalized by human skin keratinocytes are effectively eradicated by standard anti-staphylococcal antibiotics. , but not , were internalized and survive within keratinocytes without inducing cytotoxicity or releasing the IL-33 danger signal. Except for rifampicin, anti-staphylococcal antibiotics in regular clinical use, including flucloxacillin, teicoplanin, clindamycin, and linezolid, did not kill internalized , even at 20-fold their standard minimal inhibitory concentration. We conclude that internalization of by human skin keratinocytes allows the bacteria to evade killing by most anti-staphylococcal antibiotics. Antimicrobial strategies, including antibiotic combinations better able to penetrate into mammalian cells are required if intracellular are to be effectively eradicated and recurrent infections prevented.