Figure 6. NhhA-induced apoptosis does not require NO.

The RAW 264.7 mouse macrophage cell line was incubated with or without 400 nM recombinant NhhA for 20 hours. If indicated cells were pretreated for 1 h with the NO synthase inhibitor S-methylisothiourea (50 µM, SMT). A: Nitrite levels in cell supernatants were determined using Griess assay. B: The expression of iNOS was detected by immunoblot analysis. C+D: Apoptotic cells were visualized using the APOPercentage kit and the relative numbers of apoptotic cells were determined by light microscopy. Values indicate mean±SD of three independent experiments. *, p<0.05 versus untreated control.