Figure 4

Depletion of CD4⁺and CD8⁺T cells during vaccination. CB6F1 mice were vaccinated with adenoviral vectors encoding F-MuLV Env and Gag with or without co-administration of vectored IFNα4 as described before. On day -3, -1, +1, +3, and +5 of vaccination, mice were injected i.p. with antibodies against CD4 or CD8 to deplete the respective T cell subset. After FV challenge infection, spleens were palpated twice a week to monitor disease progression (A). Viral loads in plasma were determined on day 10 p.c. (B), viral loads in spleen were analyzed on day 21 p.c. (C). For the analysis of T cell induction, mice were immunized once with the indicated vectors and the expression of CD43, CD44, CD62L and CCR7 on CD4+ T cells in the draining lymph nodes was analyzed 10 days after immunization (D). The graphs show data of four mice per group. Statistically significant differences (P < 0.05) compared to unvaccinated control mice (*) or mice vaccinated with Env- plus Gag-encoding vectors (#) are indicated.