Protective humoral and CD4(+) T cellular immune responses of Staphylococcus aureus vaccine MntC in a murine peritonitis model

Staphylococcus aureus can cause different types of diseases from mild skin infections to life-threatening sepsis worldwide. Owing to the emergence and transmission of multidrug-resistant strains, developing an impactful immunotherapy especially vaccine control approach against S. aureus infections is increasingly encouraged and supported. S. aureus manganese transport protein C (MntC), which is a highly-conserved cell surface protein, can elicit protective immunity against S. aureus and Staphylococcus epidermidis. In this study, we evaluated the humoral immune response and CD4(+) T cell-mediated immune responses in a mouse peritonitis model. The results showed that MntC-specific antibodies conferred an essential protection for mice to reduce invasion of S. aureus, which was corroborated via the opsonophagocytic killing assay and passive immunization experiment in mice, and moreover MntC-induced Th17 played a remarkable part in preventing S. aureus infection since the MntC-induced protective immunity decreased after neutralization of IL-17 by antibody in vivo and the Th17 adoptive transferred-mice could partly resist S. aureus challenge. In conclusion, we considered that the MntC-specific antibodies and MntC-specific Th17 cells play cooperative roles in the prevention of S. aureus infection.