Mediator responses of alveolar macrophages and kinetics of mononuclear phagocyte subset recruitment during acute primary and secondary mycobacterial infections in the lungs of mice

Little is known about the activation program induced in alveolar macrophages upon phagocytosis of mycobacteria and the concomitant mononuclear phagocyte migratory responses that shape the acute phase of mycobacterial infection. Using high-speed cell sorting in conjunction with real-time RT-PCR analysis, we show that sorted alveolar macrophages of transgenic CX3CR1+/GFP mice infected with red fluorescent labeled Mycobacterium bovis BCG (M. bovis BCG) exhibited weak transcriptional changes of lysosomal cathepsins B, L, D, K and S, whereas antimicrobial cathepsin G was strongly induced upon infection. Moreover, mRN…