M. tuberculosis and SR-B1 Figure 4. The role of SR-B1 in vivo following low dose infection with Mtb. Wild type C57/BL6 and SR-B12/2 mice were infected with 100 CFU Mycobacterium tuberculosis H37Rv by aerosol route and sacrificed after 2 and 4 months. (A) Body weight was monitored throughout the course of the experiment and is presented as % of original body weight (time of infection) with the SEM shown as solid lines for wild type animals and dashed lines for SR-B12/2 mice. Lungs of infected animals were analysed at 2 and 4 months for histopathology by H&E staining (B). Also shown is a lung section showing the presence of clefts of accumulated cholesterol that were observed in some inflammatory foci in infected SR-B12/2 mice. Lung sections after 4 months of infection were further anlaysed by morphometric analysis to calculate the sizes of the inflammatory lesions (C). Lung homogenates were analysed at 2 and 4 months for bacterial burden (D), as well as the production of TNF, IFNc, IL10, IL12p70 and IL6 (E) with the black circles representing wild type and the open circles representing SR-B12/2 animals. Shown are the data from individual mice and the median value. doi:10.1371/journal.pone.0008448.g004 PLoS ONE | www.plosone.org 7 December 2009 | Volume 4 | Issue 12 | e8448