Interleukins are a group of cytokines that are expressed by white blood cells (leukocytes, hence the -leukin) as a means of communication (inter-). A list of interleukins with function:
IL-1: (secreted by macrophages), induces acute phase reaction
IL-2: (secreted by T cells) stimulates growth and differentiation of T cell response.
IL-3: (secreted by T cells), stimulates bone marrow stem cells.
IL-4: involved in proliferation of B cells, and the development of T cells and mast cells. Role in allergic responses.
IL-5: role in stimulation of B cells, eosinophil production, IgA production
IL-6: (secreted by macrophages) induces acute phase reaction
IL-7: involved in B, T and NK cell survival, development and homeostasis
IL-8: Neutrophil chemotaxis
IL-9: stimulates mast cells
IL-10: inhibits Th1 cytokine production
IL-11: acute phase protein production
IL-12: NK cell stimulation, Th1 cells induction
IL-13: Stimulates growth and differentiation of B-Cells, inhibits Th1 cells and the production of macrophage inflammatorycytokines
IL-17: Induces production of inflammatorycytokines
IL-18: Induces production of Interferon-Gamma (IFNy)