Figure 4. Feedback cycle of NOX2/ROS and IL-1β activation in mφs infected by T. cruzi.

THP-1 mφs were infected with T. cruzi as in Fig. 1, and incubated for 3 h (A,C,E) or 18 h (B,D,F,G) in presence of NOX2 inhibitors (diphenylene iodinium (DPI) or apoCynin), ROS scavenger (N-acetylcysteine (NAC)) or IL-1β antibody. (A–D) NOX2 inhibitors decreased ROS and IL-1β levels in infected mφs. Shown are (A&B) H₂DCFDA oxidation by intracellular ROS, resulting in formation of fluorescent DCF by fluorimetry and (C&D) IL-1β release in supernatants determined by an ELISA. (E&F) Treatment with anti-IL-1β antibody decreased the ROS levels in infected mφs. (G) Effect of ROS inhibitors on intracellular parasite burden, as determined by qPCR, in infected mφs.