Induction of CD8+ T-lymphocyte responses to a secreted antigen of Mycobacterium tuberculosis by an attenuated vaccinia virus.
Protective immunity against Mycobacterium tuberculosis infection requires the activation of mycobacterium-specific CD8+ T cells, as well as CD4+ T cells. Therefore, optimizing strategies that stimulate CD8+ T cells recognizing dominant mycobacterial antigens, including secreted proteins, may lead to the development of more effective vaccines against tuberculosis. To generate a viral vaccine that is safe in humans, the early secreted protein, MPT64, was expressed in the attenuated vaccinia virus (VV) strain, modified vaccinia virus Ankara (MVA-64). The immunogenicity of MVA-64 was compared with that of the Western Reserve strain of VV (VVWR-64). The replication-defective MVA-64 was as efficient as VVWR-64 in inducing specific antibodies and cytolytic T-cell responses to a defined H-2-Db-restricted epitope on MTP-64. In addition, priming with MPT64-expressing plasmid DNA (DNA-64), and boosting with either MVA-64 or VVWR-64, markedly enhanced MPT64-specific cytolytic and IFN-gamma-producing CD8+ T-cell responses. These findings suggest that MVA may be a suitable vaccine carrier for stimulating mycobacterium-specific CD8+ T-cell responses and may be particularly relevant for developing vaccines for use in regions endemic for tuberculosis and HIV infection.
Feng
C G
CG
Centenary Institute of Cancer Medicine and Cell Biology, Newtown, NSW, Australia.
Blanchard
T J
TJ
Smith
G L
GL
Hill
A V
AV
Britton
W J
WJ
D017088:AIDS-Related Opportunistic Infections / Q000276:immunology / Q000517:prevention & control; D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology*; D001500:BCG Vaccine / Q000235:genetics / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005260:Female; D006801:Humans; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D014376:Tuberculosis / Q000276:immunology / Q000517:prevention & control; D014613:Vaccines, Attenuated / Q000235:genetics / Q000276:immunology; D014616:Vaccinia virus / Q000276:immunology*; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology*
D000942:Antigens, Bacterial; D001500:BCG Vaccine; D014613:Vaccines, Attenuated; D014765:Viral Vaccines