Panton-Valentine leukocidin is not a virulence determinant in murine models of community-associated methicillin-resistant Staphylococcus aureus disease

(See the editorial commentary by Nauseef, on pages XXX–XX.) Increases in the incidence and severity of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections have spawned efforts to define unique viru-lence properties among prevalent strains. Panton-Valentine leukocidin (PVL), a pore-forming cytotoxin, has garnered attention because of its epidemiologic association with CA-MRSA.Using both the clinical isolate LAC,which is repre-sentative of the epidemicUSA300 strain, and its isogenic PVL-negative strain inmurinemodels of staphylococcal skin infec-tion and pneumonia, we expanded upon recent studies by assessing the contributionofPVL in thegeneticbackgroundof BALB/c mice. The data presented in this report support the observation that PVL does not contribute to the pathogenesis of staphylococcal infection of mice