T cells are central to cell-mediated immunity, orchestrating immune responses to infections and tumors. They differentiate into distinct subsets, primarily CD4+ helper T cells and CD8+ cytotoxic T cells, both of which arise from naive T cells. Cytokines play a pivotal role in guiding the development, activation, and survival of these T cells.

Specifically, interleukin-2 (IL-2), interleukin-7 (IL-7), interleukin-15 (IL-15), and interleukin-21 (IL-21) are key cytokines that influence the development and function of natural killer T (NKT) cells, a specialized subset of T cells with characteristics of both NK cells and conventional T cells. These cytokines promote NKT cell maturation, survival, and activation, enabling them to rapidly respond to infections and tumors by producing a variety of cytokines and exerting cytotoxic effects.

In summary, the coordinated interaction of cytokines with naive T cells and NKT cells is crucial for robust immune responses, playing a significant role in immunity against pathogens and malignancies.