P2Y₂ Receptor Induces L. amazonensis Infection Control in a Mechanism Dependent on Caspase-1 Activation and IL-1β Secretion

Figure 4

Control of L. amazonensis infection by UTP and ATP involves IL-1R signaling. (a) Peritoneal macrophages from WT and CASP 1,11^-/- mice were infected with L. amazonensis promastigotes for 1 h and treated with UTP for 30 min. Cell culture supernatants were harvested 4 h later. Uninfected cells were primed with LPS (1 μg/mL) for 2 h followed by ATP (3 mM), as the second signal (a positive control). IL-1β was measured 6 h later in the positive control group. (b–d) BALB/c-infected macrophages untreated (e–g) or treated with IL-1Ra (100 ng/mL) for 30 min prior (c, f) UTP and (d, g) ATP pulse for 30 min. Twenty-four hours after nucleotide treatment, cells were fixed and stained using the panoptic kit to measure parasitic load using the “infection index” (h, i). Data are of three independent experiments performed in triplicate, with pools of 3–4 animals in each experiment. and relative to the untreated group (one-way analysis of variance followed by Tukey’s test).

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