Fig 3. Effect of exogenous rGal–1 in T. cruzi infection.

HL–1 cells were incubated with rGal–1 (10 and 50 μg/ml) for 24 h and then infected with trypomastigotes of both strains. After 4 dpi with T. cruzi Tulahuén (A) or Brazil strain (D), cells were fixed and stained with an anti-T. cruzi mouse serum. Representative images are shown in (B) and (E). Similar experiments were performed after 2 dpi with T. cruzi of the Tulahuén (C) or Brazil strains (F). In this case, some wells were treated with 100 mM lactose, added simultaneously with rGal–1. G) HL–1 cells transfected with pcDNA3-Gal–1 vector or empty vector (mock) were infected with trypomastigotes of both strains, in the presence or absence of 100 mM lactose. Cells were fixed and stained after 2 dpi, with an anti-T. cruzi mouse serum. In all cases, the percentage of infected cells was determined by counting an average of 3,500 cells in each slide on 3–5 distinct coverslips in randomly selected fields. Results are expressed as mean ± SEM of triplicates determinations from three independent experiments. Statistical analysis was performed using one-way ANOVA followed by Tukey test. *p<0.05; **p<0.01; ***p<0.001.