Augmenting Staphylococcal infection: the importance of timing

Staphylococcus aureus (S. aureus) acts as a commensal in the microbiome of the skin and nasopharynx. However, on gaining access to the bloodstream it can cause an array of pathogenic outcomes. S. aureus can crowdsource the microflora to assist in becoming an opportunistic pathogen as our lab has recently published findings that co-inoculation of S. aureus with commensals, acting as pro-infectious agents, leads to a much more robust, virulent infection. This benefits S. aureus at doses where it would otherwise be cleared by the immune system. Pro-infectious agents do not need to be live commensals as isolated cell wall peptidoglycan also augments infection. This work aimed to assess the effects of inoculation with pro-infectious agents before and after infection with S. aureus. It was found that pro-infectious agents needed to be co-administered in order to fully augment infection. This gives mechanistic insight where S. aureus and the pro-infectious agents need to be in the same local environment or phagocyte to augment infection.