Fig. 6.

Chicken cytokines increase E. tenella egress from PBMCs. Cells were infected overnight with E. tenella sporozoites at a 1:1 ratio, free parasites were removed by washing, and the cells were incubated for 3 h with cell culture supernatants containing recombinant IFN-γ, IL-2, or IL-15, with supernatant from nonexpressing COS-7 cells (control), or with the indicated concentrations of swine IL-13 as an additional negative control. The percentage of egress was calculated as described in Materials and Methods. Each bar represents the mean with SEM (n = 3). *, P < 0.05, comparing cytokines with the respective dilution of the negative control.