Which cytokine is known for enhancing the proliferation of cytotoxic T cells?

Interleukin-2 (IL-2) is a key cytokine known for its critical role in the immune response, particularly in enhancing the proliferation of cytotoxic T cells. After T cell activation, IL-2 is produced primarily by CD4+ T helper cells and has an autocrine effect, allowing these activated T cells to proliferate and differentiate into effector cells. This proliferation is crucial for mounting an effective immune response against pathogens and tumor cells.

IL-2 also plays a role in the survival and memory formation of T cells, contributing to a more robust long-term immune defense. Its ability to stimulate T cell growth makes it essential for both adaptive immunity and the expansion of cytotoxic T lymphocytes (CTLs), which are vital for killing infected or cancerous cells.

In contrast, other cytokines listed have different functions in the immune system. Interleukin-1 is important in inflammation but does not directly enhance T cell proliferation. Interleukin-10 is primarily an anti-inflammatory cytokine that helps regulate immune responses and can inhibit the action of T cells. Interferon-alpha plays a significant role in antiviral responses but does not specifically enhance the proliferation of cytotoxic T cells like IL-2 does.