Figure 4.

Adoptive transfer of immune responses by ex vivo-transduced dendritic cell fractions. (A) CTL responses from naive recipients of ex vivo-transduced dendritic and monocyte cells examined by adoptive transfer. A total of 1 × 10⁶ cells were injected per naive recipient. The splenocytes from two individual recipient mice were tested in a standard CTL assay using BC-env (• and ✖) and BC/β-gal (▵ and ○) targets. Macrophage cultures processed in a similar fashion did not elicit CTL activity. (B) Comparison between fibroblast and dendritic cells in inducing immune responses. Naive recipient mice were injected once intraperitoneally with either BC-env (three mice each per dose) or in vitro transduced dendritic cell fractions (nine mice total) as described above. Each symbol represents an individual animal. Net CTL lysis at effector-to-target cell ratios of 100 was plotted against the estimated number of cells expressing antigen. The number of dendritic cells expressing HIV env/rev was estimated from luciferase expression assays. Mice that registered 15% net lysis were considered to be positive for induction of immune responses. At fibroblast doses below 1 × 10⁴, there were three mice per group whose symbols overlap.