This report summarizes the ASEV-CzeSEV Joint Meeting on Extracellular Vesicles (EVs), held at the Medical University of Vienna in September 2024. The conference focused on introducing and expanding EV research and infrastructure within the Czech Republic and Austria, highlighting areas for collaboration. Key sessions featured research on EV-based diagnostics, tissue regeneration, interspecies communication and therapeutic applications, with an emphasis on shared resources and cross-border partnerships. The program included oral and poster presentations on EV engineering, new isolation techniques, and potential clinical applications, as well as industry updates on the latest EV technologies. The meeting concluded with awards for outstanding presentations reflecting the quality of work presented. Following the conference, a dedicated workshop was held on flow cytometry analysis of EVs, allowing participants to deepen their technical expertise in EV characterization. This report captures the main discussions, findings, and collaborative opportunities explored at the ASEV-CzeSEV meeting, signaling strong regional support for advancing EV research.

• Keywords
• EV biomarkers, EV isolation techniques, EV therapeutics, Extracellular vesicles (EVs), cancer diagnostics, cellular and interspecies communication, tissue regeneration,
• Publication type
• Journal Article MeSH

Escherichia coli A0 34/86 (EcO83) is a probiotic strain used in newborns to prevent nosocomial infections and diarrhoea. This bacterium stimulates both pro- and anti-inflammatory cytokine production and its intranasal administration reduces allergic airway inflammation in mice. Despite its benefits, there are concerns about the use of live probiotic bacteria due to potential systemic infections and gene transfer. Extracellular vesicles (EVs) derived from EcO83 (EcO83-EVs) might offer a safer alternative to live bacteria. This study characterizes EcO83-EVs and investigates their interaction with host cells, highlighting their potential as postbiotic therapeutics. EcO83-EVs were isolated, purified, and characterised following the Minimal Information of Studies of Extracellular Vesicles (MISEV) guidelines. Ex vivo studies conducted in human nasal epithelial cells showed that EcO83-EVs increased the expression of proteins linked to oxidative stress and inflammation, indicating an effective interaction between EVs and the host cells. Further in vivo studies in mice demonstrated that EcO83-EVs interact with nasal-associated lymphoid tissue, are internalised by airway macrophages, and stimulate neutrophil recruitment in the lung. Mechanistically, EcO83-EVs activate the NF-κΒ signalling pathway, resulting in the nitric oxide production. EcO83-EVs demonstrate significant potential as a postbiotic alternative to live bacteria, offering a safer option for therapeutic applications. Further research is required to explore their clinical use, particularly in mucosal vaccination and targeted immunotherapy strategies.

• Keywords
• EVs, Ec083, NF‐κΒ signalling, bacterial extracellular vesicles, macrophage, nitric oxide, postbiotics, probiotic,
• MeSH
• Administration, Intranasal * MeSH
• Epithelial Cells metabolism   MeSH
• Escherichia coli * metabolism   MeSH
• Extracellular Vesicles * metabolism   MeSH
• Humans MeSH
• Lymphoid Tissue metabolism   MeSH
• Macrophages metabolism   MeSH
• Mice MeSH
• NF-kappa B metabolism   MeSH
• Oxidative Stress MeSH
• Lung microbiology   metabolism   MeSH
• Probiotics * administration & dosage   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• NF-kappa B MeSH

• Publication type
• Published Erratum MeSH