Exosomes secreted by microglia contribute to virus persistence and demyelinating disease

Loading...
Thumbnail Image

Persistent link to this item

Statistics
View Statistics

Journal Title

Journal ISSN

Volume Title

Title

Exosomes secreted by microglia contribute to virus persistence and demyelinating disease

Published Date

2020-09

Publisher

Type

Thesis or Dissertation

Abstract

Multiple sclerosis (MS) is a chronic autoimmune-mediated demyelinating disease that affects more than 2.3 million people worldwide, especially young adults. The etiology is unknown, and effective treatments are unavailable. Viral infection(s) has been postulated to play a critical role in the initiation and progression of MS. My study utilizes a mouse model called Theiler’s murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD) to better understand human MS. In TMEV-IDD, microglia, a resident macrophage in the central nervous system (CNS), are persistently infected with TMEV. As a result, the infected microglia produce an innate immune response that has been shown to contribute to bystander damage, bystander activation, and inflammation in the CNS, ultimately leading to demyelination. My central hypothesis is that exosomes secreted by microglia during TMEV infection may play an important role in sustaining persistence of virus and inflammation in the CNS, contributing to the development of demyelinating disease. We found that exosomes secreted by microglia during the acute phase (2 days post infection, dpi) and chronic phase (starting at 63dpi) of TMEV infection have altered surface markers and importantly, contain viral RNA/genome. We discovered that these exosomes are able to transfer viral RNA to uninfected CNS and infiltrating bystander cells to activate an innate immune response including expression of type I IFNs, pro-inflammatory cytokines, chemokines, and effector molecules. This activation was prominently triggered by the recognition viral RNA in exosomes by innate immune receptors. Naïve mice injected with exosomes secreted by microglia during TMEV infection showed microglia activation, neuroinflammation, and demyelination. In summary, these findings shed light on the role of exosomes in maintaining viral persistence and sustaining inflammation which are crucial in the development of virus-induced demyelinating disease in mice, and possibly human MS. The knowledge from this work may allow for identification of new therapeutic targets or disease-modifying strategies to treat demyelinating disease in human MS.

Keywords

Description

University of Minnesota Ph.D. dissertation. September 2020. Major: Comparative and Molecular Biosciences. Advisor: Julie Olson. 1 computer file (PDF); xii, 137 pages.

Related to

Replaces

License

Collections

Series/Report Number

Funding information

Isbn identifier

Doi identifier

Previously Published Citation

Suggested citation

Luong, Nhungoc. (2020). Exosomes secreted by microglia contribute to virus persistence and demyelinating disease. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/220590.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.