Abstract: This invention relates to methods and compositions useful for delivering antigens to dendritic cells which are then useful for inducing T antigen specific cytotoxic T lymphocytes. This invention also provides assays for evaluating the activity of cytotoxic T lymphocytes. According to the invention, antigens are provided to dendritic cells using a viral vector such as influenza virus which may be modified to express non-native antigens for presentation to the dendritic cells. The dendritic cells which are infected with the vector are then capable of presenting the antigen and inducing cytotoxic T lymphocyte activity or may also be used as vaccines.