Fig. 2.

Effect of L. major and L. tropica promastigotes on NO production by macrophages. Macrophages were infected with 10 promastigotes of L. tropica or L. major /cell for 4 h. Cells were kept either without stimulus or stimulated with IFN-γ (10 ng/ml) and LPS (50 ng/ml) in presence or absence of L-NMMA (1 mg/ml). The supernatants were collected and nitrite concentrations were evaluated by Griess reaction at 24 h post-infection (a) and 48 h post-infection (b). Results are expressed as mean ± SEM from six independent experiments, each performed in duplicate. Data were analyzed using one way ANOVA test with Tukey’s post-hoc test for multiple comparisons. *P < 0.05, **P < 0.01. Abbreviation: ns, not significant