Efficient protection against Mycobacterium tuberculosis by vaccination with a single subdominant epitope from the ESAT-6 antigen.

While this epitope was shown to be subdominant to a second ESAT-6 epitope also described in the study (1-20), it offered significant protection against challenge with virulent Mycobacterium tuberculosis, while epitope 1-20 did not. Bacterial numbers were quantified in both the lungs and the spleen. Immunization with ESAT-6, ESAT-6 short-term culture filtrate, or BCG all showed protective effects.