Development of an MTB39A protein-based Mycobacterium tuberculosis nanoparticle vaccine candidate

Tuberculosis (TB), a human and animal disease caused by Mycobacterium tuberculosis ( M.tb ), has the highest global mortality rate after coronavirus disease 2019 (COVID-19) and poses a major public health threat to China and several countries worldwide. Since 1890, vaccine candidates for various forms of TB have been developed for different age groups, but these vaccine candidates have not provided good protection in adolescents and adults in clinical trials. To help prevent and control the spread of TB, the development of a safe and effective TB vaccine is important. Studies conducted in recent years have shown that MTB39A has good immunogenicity and that the baculovirus expression vector systems have promising applications in vaccine development. Accordingly, in this study, we expressed the MTB39A protein via an insect-baculovirus surface display expression system, and the obtained recombinant baculovirus surface-displayed particles were used as subunit vaccines for the immunization of BALB/c mice. The results showed that the rvAc-71cA/rvAc-MTB39A recombinant baculovirus surface-displayed particles exhibited good immunogenicity in mice and could be considered potential candidates for further development of more effective genetically engineered vaccines based on the MTB39A protein, providing a solid experimental foundation for the further development of vaccines against TB and for the development of vaccines for other associated diseases using the baculovirus expression system.