Cytokines are key mediators of immune regulation, orchestrate communication between immune cells, and play a pivotal role in shaping the immune landscape during chronic infection and cancer. The therapeutic potential of IL-15/IL-15Rα and IL-12 has been explored individually in various immunotherapeutic strategies, though not as a combination. Therefore, we investigated whether the combination of IL-15/IL-15Rα and IL-12 treatment would enhance the potency and quality of either NK cells, SIV-specific CD8 T cells, or both, compared with single cytokine treatment. Our findings reveal that