The present invention contemplates methods for the generation of human antigen-specific T lymphocytes. The methods employ MHC class-II targeting signals fused to an antigen or fragment thereof to obtain MHC class presentation of RNA coded proteins. Accordingly, the present invention concerns expression vectors comprising MHC class-II targeting signal and at least one antigen or fragment thereof and its use for the in vitro generation of antigen-specific T lymphocytes. T cell clones and T cell receptors (TCRs) specific for tumor antigens or viral antigens are also described.