Fig 2. Nitrite (A) and cytokines TNF-α (B) and IL-6 (C) production by IFN-γ primed macrophages stimulated with LPG and live parasites.

Cells were pre-incubated with IFN-γ (3 IU/mL) for the 18 h then 10 μg/mL of LPG, and supernatants used for cytokine and nitrite measurements were collected 48 h latter. Fresh medium alone was used as negative control cells and LPS (100 ng/mL) as a positive control. Nitrite concentration was measured by Griess reaction and cytokine concentrations were determined by flow cytometry. C = negative control; LPG PH8 = L. amazonensis LPG PH8 strain; LPG Jos = L. amazonensis LPG Josefa strain; La PH8 = L. amazonensis PH8 live promastigotes and La Jos = L. amazonensis Josefa live promastigotes. Results represent the mean ± SD of 6 experiments in duplicate, * = P< 0.05 was considered significant.