Vaccine Created to Defend Against Staphylococcus aureus Biofilms in Cases of Severe Osteomyelitis

Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterium that causes infections to be especially difficult to treat. S. aureus has become a particularly significant problem in hospitals, where they often grow as biofilms and are currently the largest contributor to nosocomial infections. In previous experimentation, multiple strains of immunogens were found to be upregulated in biofilm growth. In this experiment, the antigens to four of these immunogens were grown in culture and combined to create a vaccine. This vaccine was administered to New Zealand white rabbits that were later infected with S. aureus tibial osteomyelitis. The initial vaccine was given on day zero of the experiment. The rabbit titer was boosted with a second injection after ten days. The animals were challenged after ten days with MRSA introduced to the left tibia. Responses to vancomycin were evaluated by examining osteomyelitic infection in the rabbit tibias. The combination of vaccine and vancomycin treatment significantly lowered levels of biofilm infection. From these results, we postulate that the vaccine was able to prevent the formation of the biofilm and vancomycin was able to destroy the remaining bacteria. From the positive results of this experiment, we plan on expanding this study to mouse models.