Final answer:
IL-2 stands for Interleukin-2, which is a cytokine crucial for T cell proliferation and function, and it plays a role in immune regulation and inflammation, relevant to the mediation of itch.
Step-by-step explanation:
IL-2 stands for Interleukin-2, which is option A. Interleukin-2 is a type of cytokine, a chemical mediator that aids in cellular communications, playing a significant role in the body's immune response. It is involved in the activities of white blood cells, which are part of the immune system, more specifically the T cells. IL-2 is an important driver for the differentiation and proliferation of T cells and is significant in the regulation of immune responses. In the context of pruritus and cutaneous mediators of itch, IL-2 along with other various interleukins and cytokines can contribute to the immune response that triggers inflammation and resultant itching sensation.