Light activated “spy” bacteria: Mediated PTT/PDT/Lysozyme hydrolysis for synergistic treatment of MRSA wound infections

Methicillin-resistant Staphylococcus aureus (MRSA) presents a significant challenge in wound infection treatment due to its antibiotic resistance and biofilm formation. To address this, we utilized Escherichia coli (Ec) as a carrier to deliver lysozyme (LYZ) and adsorb the photosensitizer indocyanine green (ICG), resulting in the Ec-LYZ-ICG multi-functional antimicrobial platform. Since both Ec and MRSA are bacteria, this platform can act as a “spy”, evading the immune surveillance of MRSA and effectively penetrating infection sites. Upon exposure to 808 nm laser irradiation, Ec-LYZ-ICG utilizes the synergistic effects of photothermal therapy (PTT) and photodynamic therapy (PDT) induced by ICG, which ruptures Ec membrane and releases LYZ. The combined PTT and PDT directly damage MRSA, while LYZ further hydrolyzes MRSA. This strategy, with its “spy-like” camouflage and penetration abilities, overcomes MRSA’s antibiotic resistance and immune evasion, providing new insights and approaches for the precise treatment of MRSA infections.