Identification of vaccine candidates for the prevention of equine strangle

Research Summary

Streptococcus equi is major bacteria that cause equine strangles, a highly contagious respiratory infection in horses. There are urgent needs for the development of safe and effective vaccines because of the limitations of current vaccines against S. equi infection.

In this study, we outline the comprehensive proteome information of various fractions, including the whole cell lysate, membrane proteome, secretory proteome, and extracellular vesicle proteome. The potential vaccine candidates are predicted using reverse vaccinology. Finally, we investigated EVs as a vaccine candidate against S. equi infection using a mouse model and validated them via immunoprecipitation-mass spectrometry (IP-MS). Importantly, a significantly higher survival rate was observed after S. equi infection using S. equi-derived EVs than using heat-killed bacteria. This study attest the usefulness of proteomics-based reverse vaccinology for identifying new vaccine candidate antigens.

Expected Outcomes

Our results suggest that S. equi-derived EVs can serve as attractive vaccine candidates against S. equi infection and the identified antigens facilitate further vaccine development

Related Figures

• [Figure 1] The proteomics-based antigen screening for Streptococcus equi
• [Figure 2]The survival plot of mice
  immunization experiments