Imaging BALB/c mice infected intratrachealy with <i>M</i>. <i>bovis</i> BCG expressing L5-tdTomato.

<p>A. IVIS images of mice infected intratrachealy with the L5-tdTomato expressing strain. Images were acquired by trans-illumination at day 1 post infection. B. Images of the lungs harvested from the infected mice at day 1 post infection. Images were acquired by epi-illumination. Colony forming units (CFU) from plating dilutions on agar plates are indicated in the images. C. Quantitative analysis of images of the infected mice and the correlation between fluorescence ratios and CFUs. Four mice were infected for each dose of bacteria from technical replicates of the same culture. Data represents one of two independent replicate experiments. Value in Y-axis represents mean of fluorescence for each dose of bacteria. The error bars are standard deviations. D. Fluorescent microscopy of lung cryosections from BCG-L5-tdTomato intratracheally infected mice. Upper left: DAPI; upper right: tdTomato; lower left: merge DAPI and tdTomato; and lower right: merge DAPI, tdTomato and phase). White bars represent 20 micrometers.