FIGURE 3.

Adoptive transfer of IEL isolated from pf^−/− and IFN-γ^−/− mice fails to protect SCID mice against E. cuniculi challenge. A, Adoptive transfer of IEL from IFN-γ^−/− and pf^−/− is unable to protect SCID mice against a lethal challenge with E. cuniculi. IEL from naive and infected pf^−/−, IFN-γ^−/−, and WT mice (n = 12 mice/group) were isolated at day 7 p.i. A total of 5 × 10⁶ IEL were injected i.p. into SCID mice (n = 6 mice/group). After 48 h, the mice were challenged orally with 2 × 10⁷ spores of E. cuniculi and the survival of the animals was monitored daily until the end of the experiment. B, IEL from WT mice were purified at day 7 p.i. CD8β⁺ and CD8β⁻ subset were separated and adoptively transferred to SCID recipients (n = 6 mice/group). The recipient animals were orally infected with 2 × 10⁷ E. cuniculi 2 days posttransfer. The survival of the animals was monitored daily until the end of the experiment.