TNF and staphylococcal infection: As previously observed with two USA300 CA-MRSA strains isolated from Memphis children with invasive staphylococcal infections [11], macrophages exposed to either of the two prototypical CA-MRSA strains studied (the USA300 strain, LAC, or the USA400 strain, MW2) secreted significantly less TNF in the presence of daptomycin as compared with vancomycin (more than 50% reduction in each strain; Figure 1).