Mycobacterium tuberculosisextracellular vesicles: exploitation for vaccine technology and diagnostic methods

Tuberculosis (TB) is a fatal epidemic disease usually caused byMycobacterium tuberculosis(Mtb). Pervasive latent infection, multidrug- and extensively drug-resistant tuberculosis (MDR- and XDR-TB), and TB/HIV co-infection make TB a global health problem, which emphasises the design and development of efficient vaccines and diagnostic biomarkers. Extracellular vesicles (EVs) secretion is a conserved phenomenon in all the domains of life. Various cargos such as nucleic acids, toxins, lipoproteins, and enzymes have been recognised in these nano-sized vesicles that may be involved in bacterial physiology and pathogenesis. The intrinsic adjuvant effect, native immunogenic cargo, sensing by host immune cells, circulation in all body fluids, and comprehensive distribution of antigens introduce EVs as a promising tool for designing novel vaccines, diagnostic biomarkers, and drug delivery systems. Genetic engineering of the EV-producing bacteria and the subsequent production of proper EVs could facilitate the development of the EV-based therapeutic applications. Recently, it was demonstrated that thick-walled mycobacteria release EVs, which contain immunodominant cargos such as lipoglycans and lipoproteins. The present article is a comprehensive review on the recent findings ofMtbEVs biology and the exploitation of EVs for the vaccine technology and diagnostic methods.

Automated summary

Tuberculosis is a deadly epidemic disease caused by Mycobacterium tuberculosis, and issues such as multidrug resistance and extensively drug-resistant tuberculosis have made efficient vaccines and diagnostic biomarkers essential. Extracellular vesicles, with their various cargos, are recognized as promising tools for designing novel vaccines, diagnostic biomarkers, and drug delivery systems in the fight against TB.