Determination of colony-forming units in lung
Right lungs from four mice at each time-point, in two different experiments, were used for bacillary load determination by colony forming counting (CFU) quantification. Lungs were homogenized with (MP Biomedicals FastPrep-24) in 1mL of 0.05% Tween-80 and the same methodology was use with spleens after weighted them. Four consecutive logarithmic dilutions were made from this homogenate. Ten microliters of each dilution were plated in duplicate on Bacto Middlebrook 7H10 agar (Difco, Detroit, MI, USA) enriched with OADC. Plates were incubated at 37ÂșC and 5% CO2 during 21 days for CFU quantification.