Extracellular Vesicles Deliver Host and Virus RNA and Regulate Innate Immune Response.
The innate immune system plays a crucial role in controlling viral infection. Pattern recognition receptors (PRRs), such as Toll-like receptors and RIG-I-like receptors, sense viral components called pathogen-associated molecular patterns (PAMPs) and trigger signals to induce innate immune responses. Extracellular vesicles (EVs), including exosomes and microvesicles, deliver functional RNA and mediate intercellular communications. Recent studies have revealed that EVs released from virus-infected cells deliver viral RNA to dendritic cells and macrophages, thereby activating PRRs in recipient cells, which results in the expression of type I interferon and pro-inflammatory cytokines. On the other hand, EVs transfer not only viral RNA but also host microRNAs to recipient cells. Recently, infection of hepatocytes with hepatitis B virus (HBV) was shown to affect microRNA levels in EVs released from virus-infected cells, leading to attenuation of host innate immune response. This suggests that the virus utilizes the EVs and host microRNAs to counteract the antiviral innate immune responses. In this review, we summarize recent findings related to the role of EVs in antiviral innate immune responses.
Department of Immunology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan. kouwaki@kumamoto-u.ac.jp.
Takahisa
T
Kouwaki
Department of Immunology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan. mokamoto@kumamoto-u.ac.jp.
Masaaki
M
Okamoto
Department of Immunology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan. htsukamo@kumamoto-u.ac.jp.
Hirotake
H
Tsukamoto
Department of Immunology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan. yfuku@kumamoto-u.ac.jp.
Yoshimi
Y
Fukushima
Department of Immunology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan. oshiumi@kumamoto-u.ac.jp.|Japan Science and Technology Agency, PRESTO, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan. oshiumi@kumamoto-u.ac.jp.
Hiroyuki
H
Oshiumi
D000818:Animals; D001692:Biological Transport; D055252:Cell-Derived Microparticles / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism; D055354:Exosomes / Q000378:metabolism; D000067128:Extracellular Vesicles / Q000378:metabolism*; D054884:Host-Pathogen Interactions / Q000235:genetics / Q000276:immunology; D006801:Humans; D007113:Immunity, Innate; D056747:Immunomodulation; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D012313:RNA / Q000235:genetics / Q000378:metabolism*; D034443:RNA Transport; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D051192:Receptors, Pattern Recognition / Q000378:metabolism; D014777:Virus Diseases / Q000235:genetics / Q000276:immunology* / Q000378:metabolism* / Q000821:virology
D035683:MicroRNAs; D012367:RNA, Viral; D051192:Receptors, Pattern Recognition; D012313:RNA
extracellular vesicles; innate immunity; microRNA; virus