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The Human Microbiome in Multiple Sclerosis: Pathogenic or Protective Constituents?

Published online by Cambridge University Press:  02 December 2014

Christopher Power ,
Joseph M. Antony ,
Kristofor K. Ellestad ,
André Deslauriers ,
Rakesh Bhat  and
Farshid Noorbakhsh
Christopher Power*
Affiliation:
Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
Joseph M. Antony
Affiliation:
Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
Kristofor K. Ellestad
Affiliation:
Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
André Deslauriers
Affiliation:
Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
Rakesh Bhat
Affiliation:
Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
Farshid Noorbakhsh
Affiliation:
Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
*
Division of Neurology, HMRC 6-11, University of Alberta, Edmonton, Alberta, T6G 2S2, Canada.
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Abstract:

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The human microbiome is comprised of commensal and pathogenic microorganisms, which exert diverse effects in close proximity to the site of intection as well as in remote tissues through immune-mediated mechanisms. Multiple infectious agents have been implicated in the pathogenesis of multiple sclerosis (MS) with variable findings depending on the agent, techniques, and disease phenotype. Herein, the contributions of individual infectious agents to MS and their effects on the immune and nervous systems are reviewed, focusing on herpes viruses, coronaviruses, retroviruses, and synchronic infections. While infectious agents are often assumed to be pathogenic, their effects might also be beneficial to the host in the long-term, depending on age and the type of immunogen/pathogen exposure, as proposed by the hygiene hypothesis. The human microbiome has potential impact on future diagnostic and therapeutic issues in MS.

Résumé:

RÉSUMÉ:

Le microbiome humain est composé d'agents microbiens commensaux et pathogènes, qui produisent différents effets tant à proximité de leur lieu d'infection qu'à distance, au moyen de mécanismes à médiation immunitaire. Plusieurs agents infectieux ont été impliqués dans la pathogenèse de la sclérose en plaques (SP). Les observations sont différentes selon l'agent, les techniques utilisées et le phénotype de la maladie. Nous revoyons ici la contribution de certains agents infectieux dans la SP et leurs effets sur le système immunitaire et le système nerveux, particulièrement les virus de l'herpès, les coronavirus, les rétrovirus et les infections synchrones. Bien qu'on présume souvent que les agents infectieux soient pathogènes, leurs effets pourraient également être bénéfiques à l'hôte à long terme, selon l'âge et le type d'exposition à un agent immunogène/pathogène, tel que proposé par “l'hypothèse de l'hygiène”. À l'avenir, le microbiome humain pourrait avoir un impact sur certains aspects diagnostiques et thérapeutiques dans la SP.

Type
Research Article
Information
Canadian Journal of Neurological Sciences , Volume 37 , supplement S2 , September 2010 , pp. S24 - S33
Copyright
Copyright © Canadian Neurological Sciences Federation 2010

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