FIG. 8.

Effect of ammonium chloride (NH₄Cl) on the initial uptake and processing of M. tuberculosis bacilli for CD4⁺ T cells. Monocytes were preincubated with or without ammonium chloride for 30 min, and then M. tuberculosis bacilli (MTB) (A) or cytosolic mycobacterial antigens (CYTOSOL) (B) were added for 120 min on initial uptake and processing of M. tuberculosis bacilli for CD4⁺ T cells and ammonium chloride treatment was continued. Monocytes then were tested in a CTL assay with a CD4⁺ T-cell line. Results are representative of three experiments. Ag, antigen; E:T ratio, effector-to-target ratio.