Outer Membrane Vesicles: Biogenesis, Composition, and Biological Functions.

has been recognized not only as a causative agent of a spectrum of gastroduodenal diseases including chronic gastritis, peptic ulcer, mucosa-associated lymphoid tissue lymphoma, and gastric cancer, but also as the culprit in several extra-gastric diseases. However, the association of infection with extra-gastric diseases remains elusive, prompting a reevaluation of the role of -derived outer membrane vesicles (OMVs). Like other gram-negative bacteria, constitutively sheds biologically active OMVs for long-distance delivery of bacterial virulence factors in a concentrated and protected form, averting the need of direct bacterial contact with distant host cells to induce extra-gastric diseases associated with this gastric pathogen. Additionally, -derived OMVs contribute to bacterial survival and chronic gastric pathogenesis. Moreover, the immunogenic activity, non-replicable nature, and anti-bacterial adhesion effect of OMVs make them a desirable vaccine candidate against infection. The immunogenic potency and safety concerns of the OMV contents are challenges in the development of OMV-based vaccines. In this review, we discuss recent advances regarding OMVs, focusing on new insights into their biogenesis mechanisms and biological functions.