Targeted Neutrophil Extracellular Traps Mimics Combat Staphylococcus aureus Infections.

Neutrophil extracellular traps (NETs) are crucial innate immune components that ensnare and neutralize pathogens. Inspired by this, we engineered a novel peptide, RFC, designed to mimic NETs' "trap-and-kill" strategy against Staphylococcus aureus infections. RFC integrates an antimicrobial peptide (KR12), a self-assembling motif (KLVFF), and a Staphylococcus-targeting sequence (CARGGLKSC). In vitro, RFC exhibited potent broad-spectrum activity (minimum inhibitory concentration (MIC) as low as 4 μM), fast bactericidal kinetics (>3-log10 reduction within 2 h at 1× MIC), inhibited biofilm formation (>92% at 2× MIC), and eradicated persister cells, while showing high biocompatibility. RFC self-assembles into nanofibrillar networks for bacterial entrapment and disrupts membranes. In vivo, RFC potently treated murine polymicrobial skin infections (99.3% wound closure) and lethal sepsis, improving survival from 16.6% to 66.7%, clearing bacteremia, and suppressing cytokines without toxicity. These findings highlight RFC as a promising antimicrobial agent, combining bacterial targeting, killing, and aggregation with tissue healing and immune activation capabilities, offering a novel strategy against challenging S. aureus infections.