Mechanisms of outer membrane vesicles in bacterial drug resistance: Insights and implications.

The emergence of antibiotic resistance has rendered the treatment of bacterial infections exceedingly challenging, with diseases caused by resistant strains often resulting in significant morbidity and mortality. Consequently, it is crucial to investigate the mechanisms underlying antibiotic resistance. Outer membrane vesicles (OMVs) are nanoscale spheres characterized by a double membrane structure, released by Gram-negative bacteria (GNB). While the mechanisms governing OMV biogenesis remain under investigation, three models have been proposed. These vesicles have been implicated in enhancing bacterial survival during antibiotic treatment and contributing to the onset and development of drug resistance through various pathways. OMVs function as a secretion system, delivering cargo that mediates intercellular communication to neighboring cells, and their closed structure facilitates this molecular delivery. Vesicles released into the extracellular compartment can protect bacteria from antibiotic treatment by promoting horizontal gene transfer, inactivating or binding antibiotics, influencing biofilm formation, and mediating bacterial gene mutations, among other mechanisms. Many studies have demonstrated that OMVs play a critical role during antibiotic exposure. An in-depth understanding of the mechanisms of OMVs in the development of bacterial drug resistance could help develop more effective therapeutic strategies to prevent persistent bacterial infections. This review focuses on summarising the latest evidence on the involvement of OMVs in the development of drug resistance, to provide ideas for future studies.