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Updated: Jun 25, 2026
09:05
MicroRNA-based Regulation of Picornavirus Tropism
Published on: February 6, 2017
Extracellular Vesicles Released by Picornavirus-Infected Cells Modify Antiviral Immune Cell Responses
Xinyi Pei1, Janine T A T Stienstra1, Margarida Viola2
1Infection Biology Section, Division Infectious Diseases & Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
Journal of Extracellular Vesicles
|June 24, 2026
Summary
Extracellular vesicles (EVs) containing picornaviruses stimulate immune cells to produce antiviral cytokines. These virus-containing EVs, particularly from monocytes, enhance immune responses more than naked viruses, aiding early antiviral defense.
Area of Science:
- Virology
- Immunology
- Cell Biology
Background:
- Picornaviruses are typically released through cell lysis.
- Emerging evidence shows viruses are packaged within extracellular vesicles (EVs) before lysis.
- EVs shield viruses from neutralizing antibodies, potentially aiding viral spread.
Purpose of the Study:
- To investigate immune cell responses to picornavirus-infected EVs.
- To compare immune stimulation by virus-containing EVs versus naked viruses.
- To elucidate the mechanisms of immune activation by virus-induced EVs.
Main Methods:
- Utilized two distinct picornaviruses for infection models.
- Co-cultured virus-infected cells and their EVs with human immune cells.
- Quantified cytokine production (Type I IFN, IP-10) via ELISA or similar assays.
- Employed receptor-blocking assays to dissect immune stimulation pathways.
Main Results:
- EVs from virus-infected cells induced significant production of Type I IFN and IP-10.
- Virus-containing EVs elicited stronger cytokine responses than equivalent amounts of naked virus.
- Monocytes were identified as key responders to virus-induced EVs.
- Both EV-enclosed virions and other EV components contributed to immune stimulation.
- EV-enclosed viruses resisted antibody opsonization, unlike naked viruses.
Conclusions:
- Virus-induced EVs are potent stimulators of innate immune responses, particularly via monocytes.
- EVs play a dual role: protecting viruses and activating immune cells for early antiviral defense.
- EV-mediated immune stimulation complements traditional antiviral mechanisms and antibody responses.
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