Past attempts to raise resistance against Mycobacterium tuberculosis using various preparations of killed mycobacteria have questioned the specificity of the generated immune response. In the present study, we have focused on the protective efficacy of experimental vaccines based on killed mycobacteria. We demonstrate that killed mycobacteria can confer high levels of protection, which can be adoptively transferred to recipient T-cell-deficient mice. Moreover, protective antigens can be found in the cell wall, membrane and cytosol of the mycobacterial cell, and hence emphasize the importance of searching for protective antigens in various compartments of the mycobacterial cell.