Also, a negative correlation was observed between the pro-IL-1β expression with the S. mansoni eggs/grams at 12 weeks after infection [Supplementary data (Fig. 5C, D)], suggesting the protective role of IL-1β in experimental infection with S. mansoni. Regarding the expression of IL-4 mRNA, it was found a negative correlation between the expression levels of this transcript and adult worms recovered from the hepatic portal system at 7 wpi [Supplementary data (Fig. 6A)]. This evidence concerns the gene IL1B and infection.