Characterization of respiratory syncytial virus M- and M2-specific CD4 T cells in a murine model

J Virol. 2009 May;83(10):4934-41. doi: 10.1128/JVI.02140-08. Epub 2009 Mar 4.

Abstract

CD4 T cells have been shown to play an important role in the immunity and immunopathogenesis of respiratory syncytial virus (RSV) infection. We identified two novel CD4 T-cell epitopes in the RSV M and M2 proteins with core sequences M(213-223) (FKYIKPQSQFI) and M2(27-37) (YFEWPPHALLV). Peptides containing the epitopes stimulated RSV-specific CD4 T cells to produce gamma interferon (IFN-gamma), interleukin 2 (IL-2), and other Th1- and Th2-type cytokines in an I-A(b)-restricted pattern. Construction of fluorochrome-conjugated peptide-I-A(b) class II tetramers revealed RSV M- and M2-specific CD4 T-cell responses in RSV-infected mice in a hierarchical pattern. Peptide-activated CD4 T cells from lungs were more activated and differentiated, and had greater IFN-gamma expression, than CD4 T cells from the spleen, which, in contrast, produced greater levels of IL-2. In addition, M(209-223) peptide-activated CD4 T cells reduced IFN-gamma and IL-2 production in M- and M2-specific CD8 T-cell responses to D(b)-M(187-195) and K(d)-M2(82-90) peptides more than M2(25-39) peptide-stimulated CD4 T cells. This correlated with the fact that I-A(b)-M(209-223) tetramer-positive cells responding to primary RSV infection had a much higher frequency of FoxP3 expression than I-A(b)-M2(26-39) tetramer-positive CD4 T cells, suggesting that the M-specific CD4 T-cell response has greater regulatory function. Characterization of epitope-specific CD4 T cells by novel fluorochrome-conjugated peptide-I-A(b) tetramers allows detailed analysis of their roles in RSV pathogenesis and immunity.

Publication types

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

MeSH terms

  • Animals
  • Antigens, Viral / immunology
  • CD4-Positive T-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / virology
  • CD8-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / virology
  • Cells, Cultured
  • Disease Models, Animal
  • Epitopes, T-Lymphocyte / immunology
  • Female
  • Genes, MHC Class II
  • Interferon-gamma / immunology
  • Interleukin-2 / immunology
  • Lung / immunology
  • Lung / virology
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Recombinant Fusion Proteins / immunology
  • Respiratory Syncytial Virus Infections / immunology*
  • Respiratory Syncytial Virus Infections / virology
  • Respiratory Syncytial Viruses / immunology*
  • Respiratory Syncytial Viruses / pathogenicity
  • Spleen / immunology
  • Spleen / virology
  • Viral Proteins / immunology*

Substances

  • Antigens, Viral
  • Epitopes, T-Lymphocyte
  • Interleukin-2
  • Recombinant Fusion Proteins
  • Viral Proteins
  • Interferon-gamma