Naked viruses can escape host cells before the induction of lysis via release in extracellular vesicles (EVs). These nanosized EVs cloak the secreted virus particles in a host-derived membrane, which alters virus-host interactions that affect infection efficiency and antiviral immunity. Currently, little is known about the viral and host factors regulating this form of virus release.
View Article and Find Full Text PDFEukaryotic cells, when exposed to environmental or internal stress, activate the integrated stress response (ISR) to restore homeostasis and promote cell survival. Specific stress stimuli prompt dedicated stress kinases to phosphorylate eukaryotic initiation factor 2 (eIF2). Phosphorylated eIF2 (p-eIF2) in turn sequesters the eIF2-specific guanine exchange factor eIF2B to block eIF2 recycling, thereby halting translation initiation and reducing global protein synthesis.
View Article and Find Full Text PDFSeveral naked virus species, including members of the Picornaviridae family, have recently been described to escape their host cells and spread infection via enclosure in extracellular vesicles (EV). EV are 50-300 nm sized lipid membrane-enclosed particles produced by all cells that are broadly recognized for playing regulatory roles in numerous (patho)physiological processes, including viral infection. Both pro- and antiviral functions have been ascribed to EV released by virus-infected cells.
View Article and Find Full Text PDFJ Extracell Vesicles
November 2018
The release and uptake of nano-sized extracellular vesicles (EV) is a highly conserved means of intercellular communication. The molecular composition of EV, and thereby their signaling function to target cells, is regulated by cellular activation and differentiation stimuli. EV are regarded as snapshots of cells and are, therefore, in the limelight as biomarkers for disease.
View Article and Find Full Text PDFIt is a long-standing paradigm in the field of virology that naked viruses cause lysis of infected cells to release progeny virus. However, recent data indicate that naked virus types of the Picornaviridae and Hepeviridae families can also leave cells via an alternative route involving enclosure in fully host-derived lipid bilayers. The resulting particles resemble extracellular vesicles (EV), which are 50 nm-1 μm vesicles released by all cells.
View Article and Find Full Text PDFIn the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells. While intensive investigation has targeted the role of EVs in different pathological processes, for example, in cancer and autoimmune diseases, the EV-mediated maintenance of homeostasis and the regulation of physiological functions have remained less explored.
View Article and Find Full Text PDFA newly uncovered means of communication between cells involves intercellular transfer of nano-sized extracellular vesicles (EV), composed of lipids, proteins, and genetic material. EV released by cells of the immune system can play a regulatory role in the induction and suppression of immune responses. These functions may be mediated not only by the bioactive lipids and proteins present in EV but also by EV-associated RNAs.
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