Identification of human T cell antigens for the development of vaccines against Mycobacterium tuberculosis

J Immunol. 2008 Dec 1;181(11):7948-57. doi: 10.4049/jimmunol.181.11.7948.

Abstract

Development of a subunit vaccine for Mycobacterium tuberculosis (Mtb) depends on the identification of Ags that induce appropriate T cell responses. Using bioinformatics, we selected a panel of 94 Mtb genes based on criteria that included growth in macrophages, up- or down-regulation under hypoxic conditions, secretion, membrane association, or because they were members of the PE/PPE or EsX families. Recombinant proteins encoded by these genes were evaluated for IFN-gamma recall responses using PBMCs from healthy subjects previously exposed to Mtb. From this screen, dominant human T cell Ags were identified and 49 of these proteins, formulated in CpG, were evaluated as vaccine candidates in a mouse model of tuberculosis. Eighteen of the individual Ags conferred partial protection against challenge with virulent Mtb. A combination of three of these Ags further increased protection against Mtb to levels comparable to those achieved with bacillus Calmette-Guérin vaccination. Vaccine candidates that led to reduction in lung bacterial burden following challenge-induced pluripotent CD4 and CD8 T cells, including Th1 cell responses characterized by elevated levels of Ag-specific IgG2c, IFN-gamma, and TNF. Priority vaccine Ags elicited pluripotent CD4 and CD8 T responses in purified protein derivative-positive donor PBMCs. This study identified numerous novel human T cell Ags suitable to be included in subunit vaccines against tuberculosis.

Publication types

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

MeSH terms

  • Adjuvants, Immunologic / genetics
  • Adjuvants, Immunologic / pharmacology
  • Animals
  • Antibodies, Bacterial / immunology
  • Antigens, Bacterial / genetics
  • Antigens, Bacterial / immunology
  • Antigens, Bacterial / pharmacology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Computational Biology
  • Disease Models, Animal
  • Female
  • Humans
  • Immunoglobulin G / immunology
  • Interferon-gamma / immunology
  • Mice
  • Mycobacterium bovis / immunology
  • Mycobacterium tuberculosis / genetics
  • Mycobacterium tuberculosis / immunology*
  • Oligodeoxyribonucleotides / genetics
  • Oligodeoxyribonucleotides / immunology
  • Oligodeoxyribonucleotides / pharmacology
  • Recombinant Proteins / genetics
  • Recombinant Proteins / immunology
  • Recombinant Proteins / pharmacology
  • Th1 Cells / immunology*
  • Tuberculosis Vaccines / genetics
  • Tuberculosis Vaccines / immunology
  • Tuberculosis Vaccines / pharmacology*
  • Tuberculosis, Pulmonary / genetics
  • Tuberculosis, Pulmonary / immunology*
  • Tuberculosis, Pulmonary / prevention & control
  • Tumor Necrosis Factor-alpha / immunology

Substances

  • Adjuvants, Immunologic
  • Antibodies, Bacterial
  • Antigens, Bacterial
  • CPG-oligonucleotide
  • Immunoglobulin G
  • Oligodeoxyribonucleotides
  • Recombinant Proteins
  • Tuberculosis Vaccines
  • Tumor Necrosis Factor-alpha
  • Interferon-gamma