FIG. 3.

β-Chemokines induce NO production in T. cruzi-infected macrophages. Thioglycolate-elicited murine macrophages were incubated with culture-derived T. cruzi trypomastigotes (Tc) in a parasite/cell ratio of 1:1 for 2 h, and the extracellular parasites were removed. This was followed by 48 h of incubation, with or without the indicated concentrations (in nanograms per milliliter) of recombinant murine MIP-1α (A), MIP-1β (B), RANTES (C), JE/MCP-1 (D), and IFN-γ (E), at 37°C in a humidified chamber containing 5% CO₂. The supernatants were harvested, and the nitrite concentration was assayed by the Griess method. The bars represent the means ± standard deviations of triplicate samples. The results shown are representative of three independent experiments.