Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches

Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly

Evaluation of Surveillance for Acute (Meningitis) Encephalitis Syndrome (AES/AMES)

This document describes an evaluation of acute (meningitis)-encephalitis syndrome (AES/AMES) surveillance established in India, Bangladesh and China. The key objectives of the project included 1) building on existing networks for syndromic surveillance and laboratory confirmation, 2) establishing laboratory-based surveillance for vaccine-preventable causes of encephalitis and meningitis, 3) enhancing capacity to use data to guide disease control and prevention programs, and 4) improving capacity to recognize new or emerging diseases. The syndromes encompass several diseases, including Japanese encephalitis (JE), pneumococcal meningitis, Haemophilus influenzae type b (Hib), and meningococcal meningitis. The purpose of the evaluation is to assess the extent to which the key objectives were met in the three project countries, compare and contrast the experiences among the countries, document the strengths and weaknesses, and make recommendations. The indicators used in the evaluation include feasibility of integration, availability of country protocols, appropriate training, data quality, sensitivity, specificity, positive predictive value, negative predictive value, representativeness, timeliness, integration with AFP surveillance, simplicity and efficiency, acceptability, usefulness, flexibility, stability, and sustainability. The criteria and standards are based on WHO recommendations. Data sources include AES/AMES epidemiologic and laboratory data sets, trip reports, country reports, field observations, and published bulletins. All countries made substantial progress in a relatively short period of time using the infrastructure and technical tools of existing surveillance and laboratory networks for acute flaccid paralysis. After one year, India and Bangladesh collects and maintains high quality epidemiologic data, exceeds targets for timeliness of reporting, and has quality-assured capacity for laboratory confirmation of Japanese encephalitis (JE) virus infection. India now has regional laboratory capacity for reference testing on virology and bacteriology. After two years of operations, China has population-based surveillance data for JE that meets targets for timeliness. Several levels have well-established capacity for laboratory confirmation of JE virus infection. The national level has the technical ability to provide proficiency testing for virology and to provide reference testing for bacteriology. In all countries, challenges in building capacity for basic bacteriology, quality control and quality assurance for all laboratory testing, and management of laboratory data

Evaluation of Three Commercially Available Japanese Encephalitis Virus IgM Enzyme-Linked Immunosorbent Assays

We evaluated performance of three commercial Japanese encephalitis virus (JEV) IgM antibody capture enzyme-linked immunosorbent assay (MAC ELISA) kits with a panel of serological specimens collected during a surveillance project of acute encephalitis syndrome in India and acute meningitis and encephalitis syndrome in Bangladesh. The serum and cerebral spinal fluid specimens had been referred to the Centers for Disease Control and Prevention (CDC) for confirmatory testing. The CDC results and specimen classifications were considered the reference standard. All three commercial kits had high specificity (95–99.5%), but low sensitivities, ranging from 17–57%, with both serum and cerebrospinal fluid samples. Specific factors contributing to low sensitivity compared with the CDC ELISA could not be determined through further analysis of the limits and dilution end points of IgM detection