Fecha de publicación: 25/12/2001 Fuente: WIPO "royal booby" The present invention relates to compositions and methods for the expression of nucleic acids or polypeptides into mature T lymphocytes. The invention relates more specifically to methods of selective gene expression into mature T lymphocytes, based on CD4-derived regulatory sequences, such as CD4-derived enhancer sequences. The invention is particularly suited for regulating gene expression into mature T lymphocytes in vitro, ex vivo or in vivo, upon genetic modification of hematopoietic precursors and maturation thereof.