Exosomes serve as novel modes of tick-borne flavivirus transmission from arthropod to human cells and facilitates dissemination of viral RNA and proteins to the vertebrate neuronal cells.

Molecular determinants and mechanisms of arthropod-borne flavivirus transmission to the vertebrate host are poorly understood. In this study, we show for the first time that a cell line from medically important arthropods, such as ticks, secretes extracellular vesicles (EVs) including exosomes that...

Full description

Bibliographic Details
Main Authors: Wenshuo Zhou, Michael Woodson, Biswas Neupane, Fengwei Bai, Michael B Sherman, Kyung H Choi, Girish Neelakanta, Hameeda Sultana
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2018-01-01
Series:PLoS Pathogens
Online Access:https://doi.org/10.1371/journal.ppat.1006764
_version_ 1818901763241017344
author Wenshuo Zhou
Michael Woodson
Biswas Neupane
Fengwei Bai
Michael B Sherman
Kyung H Choi
Girish Neelakanta
Hameeda Sultana
author_facet Wenshuo Zhou
Michael Woodson
Biswas Neupane
Fengwei Bai
Michael B Sherman
Kyung H Choi
Girish Neelakanta
Hameeda Sultana
author_sort Wenshuo Zhou
collection DOAJ
description Molecular determinants and mechanisms of arthropod-borne flavivirus transmission to the vertebrate host are poorly understood. In this study, we show for the first time that a cell line from medically important arthropods, such as ticks, secretes extracellular vesicles (EVs) including exosomes that mediate transmission of flavivirus RNA and proteins to the human cells. Our study shows that tick-borne Langat virus (LGTV), a model pathogen closely related to tick-borne encephalitis virus (TBEV), profusely uses arthropod exosomes for transmission of viral RNA and proteins to the human- skin keratinocytes and blood endothelial cells. Cryo-electron microscopy showed the presence of purified arthropod/neuronal exosomes with the size range of 30 to 200 nm in diameter. Both positive and negative strands of LGTV RNA and viral envelope-protein were detected inside exosomes derived from arthropod, murine and human cells. Detection of Nonstructural 1 (NS1) protein in arthropod and neuronal exosomes further suggested that exosomes contain viral proteins. Viral RNA and proteins in exosomes derived from tick and mammalian cells were secured, highly infectious and replicative in all tested evaluations. Treatment with GW4869, a selective inhibitor that blocks exosome release affected LGTV loads in both arthropod and mammalian cell-derived exosomes. Transwell-migration assays showed that exosomes derived from infected-brain-microvascular endothelial cells (that constitute the blood-brain barrier) facilitated LGTV RNA and protein transmission, crossing of the barriers and infection of neuronal cells. Neuronal infection showed abundant loads of both tick-borne LGTV and mosquito-borne West Nile virus RNA in exosomes. Our data also suggest that exosome-mediated LGTV viral transmission is clathrin-dependent. Collectively, our results suggest that flaviviruses uses arthropod-derived exosomes as a novel means for viral RNA and protein transmission from the vector, and the vertebrate exosomes for dissemination within the host that may subsequently allow neuroinvasion and neuropathogenesis.
first_indexed 2024-12-19T20:24:55Z
format Article
id doaj.art-e38ce0540a6b42aeb5f460528cb3c817
institution Directory Open Access Journal
issn 1553-7366
1553-7374
language English
last_indexed 2024-12-19T20:24:55Z
publishDate 2018-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Pathogens
spelling doaj.art-e38ce0540a6b42aeb5f460528cb3c8172022-12-21T20:06:51ZengPublic Library of Science (PLoS)PLoS Pathogens1553-73661553-73742018-01-01141e100676410.1371/journal.ppat.1006764Exosomes serve as novel modes of tick-borne flavivirus transmission from arthropod to human cells and facilitates dissemination of viral RNA and proteins to the vertebrate neuronal cells.Wenshuo ZhouMichael WoodsonBiswas NeupaneFengwei BaiMichael B ShermanKyung H ChoiGirish NeelakantaHameeda SultanaMolecular determinants and mechanisms of arthropod-borne flavivirus transmission to the vertebrate host are poorly understood. In this study, we show for the first time that a cell line from medically important arthropods, such as ticks, secretes extracellular vesicles (EVs) including exosomes that mediate transmission of flavivirus RNA and proteins to the human cells. Our study shows that tick-borne Langat virus (LGTV), a model pathogen closely related to tick-borne encephalitis virus (TBEV), profusely uses arthropod exosomes for transmission of viral RNA and proteins to the human- skin keratinocytes and blood endothelial cells. Cryo-electron microscopy showed the presence of purified arthropod/neuronal exosomes with the size range of 30 to 200 nm in diameter. Both positive and negative strands of LGTV RNA and viral envelope-protein were detected inside exosomes derived from arthropod, murine and human cells. Detection of Nonstructural 1 (NS1) protein in arthropod and neuronal exosomes further suggested that exosomes contain viral proteins. Viral RNA and proteins in exosomes derived from tick and mammalian cells were secured, highly infectious and replicative in all tested evaluations. Treatment with GW4869, a selective inhibitor that blocks exosome release affected LGTV loads in both arthropod and mammalian cell-derived exosomes. Transwell-migration assays showed that exosomes derived from infected-brain-microvascular endothelial cells (that constitute the blood-brain barrier) facilitated LGTV RNA and protein transmission, crossing of the barriers and infection of neuronal cells. Neuronal infection showed abundant loads of both tick-borne LGTV and mosquito-borne West Nile virus RNA in exosomes. Our data also suggest that exosome-mediated LGTV viral transmission is clathrin-dependent. Collectively, our results suggest that flaviviruses uses arthropod-derived exosomes as a novel means for viral RNA and protein transmission from the vector, and the vertebrate exosomes for dissemination within the host that may subsequently allow neuroinvasion and neuropathogenesis.https://doi.org/10.1371/journal.ppat.1006764
spellingShingle Wenshuo Zhou
Michael Woodson
Biswas Neupane
Fengwei Bai
Michael B Sherman
Kyung H Choi
Girish Neelakanta
Hameeda Sultana
Exosomes serve as novel modes of tick-borne flavivirus transmission from arthropod to human cells and facilitates dissemination of viral RNA and proteins to the vertebrate neuronal cells.
PLoS Pathogens
title Exosomes serve as novel modes of tick-borne flavivirus transmission from arthropod to human cells and facilitates dissemination of viral RNA and proteins to the vertebrate neuronal cells.
title_full Exosomes serve as novel modes of tick-borne flavivirus transmission from arthropod to human cells and facilitates dissemination of viral RNA and proteins to the vertebrate neuronal cells.
title_fullStr Exosomes serve as novel modes of tick-borne flavivirus transmission from arthropod to human cells and facilitates dissemination of viral RNA and proteins to the vertebrate neuronal cells.
title_full_unstemmed Exosomes serve as novel modes of tick-borne flavivirus transmission from arthropod to human cells and facilitates dissemination of viral RNA and proteins to the vertebrate neuronal cells.
title_short Exosomes serve as novel modes of tick-borne flavivirus transmission from arthropod to human cells and facilitates dissemination of viral RNA and proteins to the vertebrate neuronal cells.
title_sort exosomes serve as novel modes of tick borne flavivirus transmission from arthropod to human cells and facilitates dissemination of viral rna and proteins to the vertebrate neuronal cells
url https://doi.org/10.1371/journal.ppat.1006764
work_keys_str_mv AT wenshuozhou exosomesserveasnovelmodesoftickborneflavivirustransmissionfromarthropodtohumancellsandfacilitatesdisseminationofviralrnaandproteinstothevertebrateneuronalcells
AT michaelwoodson exosomesserveasnovelmodesoftickborneflavivirustransmissionfromarthropodtohumancellsandfacilitatesdisseminationofviralrnaandproteinstothevertebrateneuronalcells
AT biswasneupane exosomesserveasnovelmodesoftickborneflavivirustransmissionfromarthropodtohumancellsandfacilitatesdisseminationofviralrnaandproteinstothevertebrateneuronalcells
AT fengweibai exosomesserveasnovelmodesoftickborneflavivirustransmissionfromarthropodtohumancellsandfacilitatesdisseminationofviralrnaandproteinstothevertebrateneuronalcells
AT michaelbsherman exosomesserveasnovelmodesoftickborneflavivirustransmissionfromarthropodtohumancellsandfacilitatesdisseminationofviralrnaandproteinstothevertebrateneuronalcells
AT kyunghchoi exosomesserveasnovelmodesoftickborneflavivirustransmissionfromarthropodtohumancellsandfacilitatesdisseminationofviralrnaandproteinstothevertebrateneuronalcells
AT girishneelakanta exosomesserveasnovelmodesoftickborneflavivirustransmissionfromarthropodtohumancellsandfacilitatesdisseminationofviralrnaandproteinstothevertebrateneuronalcells
AT hameedasultana exosomesserveasnovelmodesoftickborneflavivirustransmissionfromarthropodtohumancellsandfacilitatesdisseminationofviralrnaandproteinstothevertebrateneuronalcells