Methods for the ex vivo generation of cells of the innate (NKT cells and NK cells) and adaptive (T cells) immune systems for use in adoptive cell transfer (ACT) are provided. The NKT cells render T cells resistant to immune suppression (e.g. they are resistant to the effects of myeloid-derived suppressor cells (MDSCs)). The method involves culturing disease-primed immune cells (obtained from a cancer patient or from a patient with an infectious disease) with i) bryostatin and ionomycin (B/I) to activate and differentiate the cells; followed by sequentially culturing the cells with a) a combination of IL-7 and IL-15 and then b) IL-2, to further differentiate the cells and to render them immune resistant. The resistant immune cells are used to treat and prevent cancer and infectious diseases.