Sublingual immunization with Mtb proteins Ag85B and ESAT-6 in the presence of α-GalCer adjuvant significantly reduces pulmonary and extra-pulmonary bacterial load: C57BL/6 female mice were immunized by the sublingual route twice at 7 day intervals with a mixture of the recombinant Mtb proteins Ag85B and ESAT-6 in the presence and absence of the adjuvant α-GalCer (α-GalCer + Proteins and Proteins, respectively) or with adjuvant alone (α-GalCer) or Bacillus Calmette-Guerin (BCG) or untreated (naïve) and challenged on day 28 with Mtb by aerosol. (Panel (A)): The bacterial burden in the spleens (Panel (B), left) and lungs (Panel (B), right) of mice in the different groups were analyzed on day 56 (28 days post challenge) as described in the methods section. Significantly lower (**, p < 0.005) bacterial burden in the spleens of mice vaccinated with either BCG or the Mtb proteins in the presence of α-GalCer adjuvant were observed when compared to naïve mice. Similar analysis in the lungs also showed significantly lower (***, p < 0.0005) bacterial burden in mice vaccinated with the Mtb proteins in the presence of α-GalCer adjuvant when compared to naïve mice. In both spleens and lungs of mice vaccinated with Mtb proteins in the presence of α-GalCer adjuvant the bacterial burden was significantly lower (*, p < 0.05) than those in mice immunized with BCG. Data shown are from one of two separate experiments each with groups of 5 mice.