Protective Immunity against Mycobacterium tuberculosis Induced by Dendritic Cells Pulsed with both CD8 + - and CD4 + -T-Cell Epitopes from Antigen 85A

Immunization with DNA followed by modified vaccinia virus Ankara strain, both expressing the antigen 85A, induced both CD4+ and CD8+ T-cell responses in BALB/c mice. Following challenge with Mycobacterium tuberculosis, this prime-boost regimen produced protection equivalent to that conferred by Mycobacterium bovis BCG. Following immunization with dendritic cells pulsed with an antigen 85A CD4+ or CD8+ restricted epitope, alone or in combination, copresentation of both epitopes on the same dendritic cell was required for protection, demonstrating that induced CD8+ T cells can play a protective role against tuberculosis.