Insights into the regulatory role of bacterial sncRNA and its extracellular delivery via OMVs.

Small noncoding RNAs (sncRNAs) play important regulatory roles in bacterial physiological processes and host-pathogen interactions. Meanwhile, bacterial outer membrane vesicles (OMVs), as naturally secreted outer membrane structures, play a vital role in the interaction between bacteria and their living environment, including the host environment. However, most current studies focus on the biological functions of sncRNAs in bacteria or hosts, while neglecting the roles and regulatory mechanisms of the OMVs that encapsulate these sncRNAs.

Recombinant outer membrane vesicles delivering eukaryotic expression plasmid of cytokines act as enhanced adjuvants against infection in mice.

The widespread prevalence of () infection remains a great challenge to human health. The existing vaccines are not ideal for preventing infection; thus, exploring highly effective adjuvants may improve the immunoprotective efficacy of vaccines. In a previous study, we found that the outer membrane vesicles (OMVs), a type of nanoscale particle spontaneously produced by Gram-negative bacteria, could act as adjuvants to boost the immune responses to vaccine antigens.

Disruption of sncRNA Improves the Protective Efficacy of Outer Membrane Vesicles against Helicobacter pylori Infection in a Mouse Model.

The outer membrane vesicles (OMVs) secreted by Helicobacter pylori contain various bacterial components, such as proteins, phospholipids, toxins, and nucleic acids, including small noncoding RNA (sncRNA), which have regulatory functions in cell envelope structure, metabolism, bacterial communication, biofilm formation, and virulence. We previously showed that knocking out sncRNAs sR-989262 and sR-2509025 at the cellular level increased interleukin 8 (IL-8) levels in mice exposed to OMVs. In this study, we show that immunization with ΔsR-989262 and ΔsR-2509025 OMVs intragastrically significantly increased immunoglobulin G (IgG) and secreted IgA levels in mice compared to wild-type OMVs and without weight changes, which indicated that sncRNA-deficient OMVs are relatively safe to immunize mice.

Outer Membrane Vesicles Derived from Serotype Typhimurium Can Deliver 2a O-Polysaccharide Antigen To Prevent 2a Infection in Mice.

Shigellosis has become a serious threat to health in many developing countries due to the severe diarrhea it causes. Shigella flexneri 2a is the principal species responsible for this endemic disease. Despite multiple attempts to design a vaccine against shigellosis, no effective vaccine has been developed yet.

Immunization With Outer Membrane Vesicles Derived From Major Outer Membrane Protein-Deficient Typhimurium Mutants for Cross Protection Against Enteritidis and Avian Pathogenic O78 Infection in Chickens.

Colibacillosis is an economically important infectious disease in poultry, caused by avian pathogenic (APEC). serovar Enteritidis ( Enteritidis) is a major cause of food-borne diseases in human circulated through poultry-derived products, including meat and chicken eggs. Vaccine control is the mainstream approach for combating these infections, but it is difficult to create a vaccine for the broad-spectrum protection of poultry due to multiple serotypes of these pathogens.

Outer Membrane Vesicles of 7.13 as Adjuvants Promote Protective Efficacy Against Infection.

(), a gram-negative bacterium in the human stomach with global prevalence, is relevant to chronic gastrointestinal diseases. Due to its increasing drug resistance and the low protective efficacy of some anti- vaccines, it is necessary to find a suitable adjuvant to improve antigen efficiency. In our previous study, we determined that outer membrane vesicles (OMVs), a multicomponent secretion generated by gram-negative bacteria, of were safe and could induce long-term and robust immune responses against in mice.