Provided is an isolated or purified T cell comprising an antigen-specific receptor, wherein the antigen-specific receptor is a T cell receptor (TCR) or a chimeric antigen receptor (CAR), wherein the T cell has been modified to express a transcription factor at a level that is higher than the level of the transcription factor expressed by a T cell that has not been modified to express the transcription factor, wherein the transcription factor is V-Myb Avian Myeloblastosis Viral Oncogene Homolog (c-Myb), a functional variant of c-Myb, or a functional fragment of c-Myb. Related populations of cells, pharmaceutical compositions, methods of treating a disease, and methods of inhibiting the differentiation of T cells are also provided.