Figure 5.
Impaired cellular immunity of IFN-γR2 −/− mice. (A) Defective contact hypersensitivity in IFN-γR2 −/− mice. Five 6-wk-old female wild-type mice and five 6-wk-old IFN-γR2 −/− mice were used in this assay. The assay was done as described in Materials and Methods. Contact hypersensitivity is expressed in the change of ear thickness (T). T = (ear thickness 24 hr after elicitation) − (baseline ear thickness). The t test was used in comparison of T in IFN-γR2 +/+ and IFN-γR2 −/− mice. (B) IFN-γR2 −/− mice were susceptible to L. monocytogenes infection. Six-week-old female mice from each genetic background were used. For each genotype, five mice were injected i.p. with 1 × 104 live L. monocytogenes. Percentage of survival represents the percentage of live mice each day.