The IL-2 receptor is a protein found on the surface of certain immune cells, such as T cells. It plays a crucial role in the immune response by binding to interleukin-2 (IL-2), a signaling molecule that helps regulate the growth, proliferation, and differentiation of these cells. There are three main types of IL-2 receptors: IL-2Rα, IL-2Rβ, and IL-2Rγ. These receptors can exist in different forms, either as low-affinity or high-affinity receptors, depending on their composition. The interaction between IL-2 and its receptor is essential for effective immune responses, including the activation of T cells during infections.