Question - In the natural progression of TB, after the acute phase of infection the bacterium will go latent and lie dormant in the body. To understand which T-cell types are most important for controlling acute versus latent Mtb infection, van Pixteren et al. 2000. Eur J Immune! 30: 3689-3698, depleted CD4+ and CD8+ T-cells from Mtb-infected mice with antibodies against their respective CD molecules. Then, they measured the amount of live bacteria recovered from the lungs as CFU. Control IgG will not deplete T-cells. The cortisone control will generally suppress the immune system. Statistically different results are marked by *.
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a. Which T-cells are most important for controlling bacterial numbers during acute infection?
b. Which T-cells are most important for controlling bacterial numbers during latent infection? Suggest how that would work.