Characterization of a heat-killed Mtb vaccination model.

<p>(A) Kinetics of Mtb colonization in vaccinated or mock-treated mice lungs. C57BL/6J mice were intraperitoneally injected with 5×10⁵ CFUs of heat-killed Erdman or with sterile PBS (mock-treated). Four weeks post-vaccination, mice were challenged with 10³ CFUs of various reporter Mtb intranasally. At indicated time points post-challenge, mice were sacrificed and the bacterial burden in the lungs determined. The pooled data for each time point are shown as means ± SEM, from at least 3 animals per data point. * indicates p<0.05 (unpaired t-test). (B) Lung pathology of vaccinated and mock-treated mice. Lungs collected at indicated time points post-challenge were fixed in 4% paraformaldehyde and subjected to routine H&E staining. Scale bar 200 µm.