AUTHOR= Frontiers Editorial Office TITLE=Expression of Concern: Manipulation of Gut Microbiota Influences Immune Responses, Axon Preservation, and Motor Disability in a Model of Progressive Multiple Sclerosis JOURNAL=Frontiers in Immunology VOLUME=11 YEAR=2020 URL=https://www.frontiersin.org/articles/10.3389/fimmu.2020.614941 DOI=10.3389/fimmu.2020.614941 ISSN=1664-3224