Non-canonical NLRP3 inflammasome activation and IL-1β signaling are necessary to L. amazonensis control mediated by P2X7 receptor and leukotriene B4
Fig 4
L. amazonensis control via ATP/P2X7 receptor was Casp-11 dependent.
Peritoneal macrophages from C57Bl/6 (panels A-C, G, and H) and Casp-11-/- (D-F) mice were infected with promastigotes of L. amazonensis at a ratio of 10:1 (Leishmania:macrophage). After 4 hours, the free parasites were washed and after 24 hours, infected cells were treated with ATP (500 μM; B and E). Infected macrophages were also treated with Z-YVAD-FMK and Z-LEVD-FMK, Casp-1 and Casp-11 inhibitors respectively, at the concentration of 2 μM 30 minutes before ATP treatment. Twenty-four hours later, the infection index was determined. Standard values represent means ± SEM of 3 independent experiments performed in triplicate. Arrows correspond to vacuoles with L. amazonensis and asterisks represent empty vacuoles. (*P < 0.05) compared to the control group (without treatment).