FIG. 3.

LM induces apoptosis and IL-12 gene expression in macrophages. (A) Differentiated THP-1 cells were incubated with either PILAM (20 μg/ml) or with LMs isolated from M. tuberculosis, M. kansasii, and M. chelonae (10 μg/ml) for 24 h. The percentage of apoptosis was determined by flow cytometry analysis of 10,000 events after cells were stained with AnnexinV and propidium iodide. (B) RAW/pIL-12-GFP cells were incubated with wither PILAM (20 μg/ml), LMs (10 μg/ml), or LPS (100 ng/ml) for 16 h, and flow cytometry was used to determine the induction of GFP-positive cells in 5,000 events. The results are the means of three independent experiments. A statistical analysis was performed as described in the legend to Fig. 2; three asterisks indicate that the P value is <0.001, and two asterisks indicate that the P value is <0.01. M.sp.-PILAM, Mycobacterium sp. PILAM; M.tb-LM, M. tuberculosis LM; M.Kan-LM, M. kansasii LM; M.Che-LM, M. chelonae LM.