Bacteria were grown to late logarithmic phase at 37°C in tryptic soy broth (Becton Dickinson and Co., Sparks, MD) and washed three times in endotoxin-free phosphate-buffered saline. Concentrations were determined by colony counts. A range of concentrations of bacteria (10 5 -10 7 CFU/mL) was studied, based upon our previously published data with other CA-MRSA strains [11] and our preliminary experiments using LAC and MW2 (data not shown).