Norovirus antagonism of B-cell antigen presentation results in impaired control of acute infection

Mucosal Immunol. 2016 Nov;9(6):1559-1570. doi: 10.1038/mi.2016.15. Epub 2016 Mar 23.

Abstract

Human noroviruses are a leading cause of gastroenteritis, and so, vaccine development is desperately needed. Elucidating viral mechanisms of immune antagonism can provide key insight into designing effective immunization platforms. We recently revealed that B cells are targets of norovirus infection. Because noroviruses can regulate antigen presentation by infected macrophages and B cells can function as antigen-presenting cells, we tested whether noroviruses regulate B-cell-mediated antigen presentation and the biological consequence of such regulation. Indeed, murine noroviruses could prevent B-cell expression of antigen presentation molecules and this directly correlated with impaired control of acute infection. In addition to B cells, acute control required MHC class I molecules, CD8+ T cells, and granzymes, supporting a model whereby B cells act as antigen presenting cells to activate cytotoxic CD8+ T cells. This immune pathway was active prior to the induction of antiviral antibody responses. As in macrophages, the minor structural protein VP2 regulated B-cell antigen presentation in a virus-specific manner. Commensal bacteria were not required for the activation of this pathway and ultimately only B cells were required for the clearance of viral infection. These findings provide new insight into the role of B cells in stimulating antiviral CD8+ T-cell responses.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Acute Disease
  • Animals
  • Antibodies, Viral / immunology
  • Antibody Formation
  • Antigen Presentation / immunology*
  • Antigen-Presenting Cells / immunology
  • Antigen-Presenting Cells / metabolism
  • Antigens, Surface / metabolism
  • B-Lymphocytes / immunology*
  • B-Lymphocytes / metabolism
  • Caliciviridae Infections / immunology*
  • Caliciviridae Infections / virology*
  • Capsid Proteins / immunology
  • Capsid Proteins / metabolism
  • Cell Line
  • Disease Models, Animal
  • Gastrointestinal Microbiome
  • Humans
  • Immunomodulation
  • Mice
  • Mice, Knockout
  • Norovirus / physiology*
  • T-Lymphocytes, Cytotoxic / immunology
  • T-Lymphocytes, Cytotoxic / metabolism

Substances

  • Antibodies, Viral
  • Antigens, Surface
  • Capsid Proteins