FIG. 6.

CD4⁺ T cells in vaccinated IFN-γ-KO mice home to the lung airways upon virus challenge. IFN-γ-KO and B6 mice were vaccinated with DNA (D) and vaccinia virus (V) in a prime-boost regimen. Inoculations were in the order D-D-V-D. One month after the last injection, vaccinated and unvaccinated mice were challenged with rSeV-env (2 × 10³ PFU/animal). Mice were given ip injections with the anti-CD8 2.43.1 mAb on days −5, −3, −1, +1, and +3 relative to rSeV-env challenge. Results show the approximate number of CD4⁺ T cells in the BAL from individual B6 (A) and IFN-γ- KO (B) mice on day 5 postchallenge, as described in Fig. 3.