Figure 7. Expression of Paracoccidioides fbp, icl and thio genes and susceptibility of yeast cells to macrophages killing during infection.

(A) Pb01 yeast cells were grown without (yeast cells) and with macrophages (yeast cells-macrophages) for 24 h in RPMI medium, and the relative expression of genes fbp (fructose-1,6-biphosphatase), icl (isocitrate lyase), and thio (3-ketoacyl-CoA thiolase) was determined. The data were normalized using the constitutive gene encoding the 60S ribosomal L34 gene as the endogenous control and are presented as relative expression in comparison to the experimental control cells value set at 1. (B) Pb01 yeast cells were previously grown in MMcM medium with carbon (4% of glucose) or absence of glucose (carbon starvation) up to 48 h and then were incubated with macrophages at a 1∶2.5 macrophages: yeast ratio, for both conditions. As demonstrated, the number of viable cells was determined by quantifying the number of colony forming units/mL (CFUs/mL) during infection from culture supernatant (non-internalized cells removed by aspiration prior to macrophages lysis) and after internalization. Data are expressed as the mean ± standard deviation of the biological triplicates of independent experiments. Student's t-test was used. *, significantly different from the control, at a p-value of ≤0.05.