Cytomegalovirus misleads its host by priming of CD8 T cells specific for an epitope not presented in infected tissues

J Exp Med. 2004 Jan 5;199(1):131-6. doi: 10.1084/jem.20031582. Epub 2003 Dec 29.

Abstract

Cytomegaloviruses (CMVs) code for several proteins that inhibit the presentation of antigenic peptides to CD8 T cells. Although the molecular mechanisms of CMV interference with the major histocompatibility complex class I pathway are long understood, surprisingly little evidence exists to support a role in vivo. Here we document the first example of the presentation of an antigenic peptide being blocked by a CMV immune evasion protein in organs relevant to CMV disease. Although this Db-restricted peptide, which is derived from the antiapoptotic protein M45 of murine CMV (mCMV), is classified as an immunodominant peptide based on response magnitude and long-term memory, adoptive transfer of M45 epitope-specific CD8 T cells did not protect against infection with wild-type mCMV. Notably, the same cells protected C57BL/6 mice infected with an mCMV mutant in which immune evasion protein m152/gp40 is deleted. These data indicate that direct presentation or cross-presentation of an antigenic peptide by professional antigen-presenting cells can efficiently prime CD8 T cells that fail in protection against CMV organ disease because m152/gp40 prevents presentation of this peptide in pathogenetically relevant tissue cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adoptive Transfer
  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / virology
  • Cytomegalovirus / immunology*
  • Cytomegalovirus / pathogenicity*
  • Cytomegalovirus Infections / immunology*
  • Humans
  • Immunologic Memory
  • Immunomagnetic Separation
  • Lymphocyte Activation