Mycobacterium tuberculosis-activated dendritic cells induce protective immunity in mice.

Activated dendritic cells are critically important in the priming of T-cell responses. In this report we show that the infection of a conditionally immortalized dendritic cell line (tsDC) with Mycobacterium tuberculosis resulted in the up-regulation of B7-1 and B7-2 co-stimulatory molecules and the induction of several inflammatory cytokines, including tumour necrosis factor-alpha and interleukin-6, -1beta and -12. In addition, we show that these activated dendritic cells were capable of eliciting antigen-specific T-cell responses and potent anti-mycobacterial protective immunity in a murine model of experimental tuberculosis infection.