Figure 6.

Gal-1 does not bind and kill the yeast form of H. capsulatum. (a) Yeasts were incubated for 1 hour at 4°C with 1.0 μM and 4.0 μM biotinylated-hrGal-1, in the presence or absence of 20 mM lactose (Gal-1 inhibitor) or sucrose (control, noninhibitor). After that, yeasts were incubated with streptavidin-FITC and labeled cells were acquired on a FACS Canto (Becton Dickinson, Mountain View, CA, USA) and analyzed in the DIVA software (Becton Dickinson). (b) As a control, HL-60 cells (1 × 10⁶) were incubated with 1 μM biotinylated-hrGal-1 for 1 hour at 4°C, in presence or absence of 20 mM lactose or sucrose. (c) Several hrGal-1 concentrations (0.5, 1.0, 2.5, 4.0, and 10 μM) were incubated with 1 × 10⁶ H. capsulatum cells during 24 and 48 h. After each time, relative fluorescent units (RFU) (560–590 nm) were measured and represent yeast cells metabolically active through the dye resazurin reagent. Data are representative of two independent experiments and expressed as the mean ± SEM.