interleukin
(in‵tĕr-loo'kĭn 
)
ABBR: IL
A type of cytokine that enables communication among leukocytes and other cells active in inflammation or the specific immune response. The result is a maximized response to a microorganism or other foreign antigen.
SEE: cell-mediated immunity; cytokine; inflammation.
ABBR: IL-1
A cytokine released by almost all nucleated cells that activates the growth and function of neutrophils, lymphocytes, and macrophages; promotes the release of additional mediators that influence immune responses; enhances production of cerebrospinal fluid; and modulates certain adrenal, hepatic, bone, and vascular smooth muscle cell activity. Interleukin-1 and tumor necrosis factors, whose actions are almost identical to those of IL-1, are involved in fever production and other systemic effects of inflammation.SEE: tumor necrosis factor.
ABBR: IL-1-β
A protein released by circulating mononuclear cells and cells within joints that stimulates multiple inflammatory responses. It is found in elevated levels in a variety of inflammatory conditions, including, for example: in the blood in septic shock or a history of myocardial infarction; in the cerebrospinal fluid in meningitis; and in synovial fluid in osteoarthritis. SYN: catabolin.ABBR: IL-2
A cytokine released primarily by activated CD4+ helper T lymphocytes. It is a major mediator of T cell proliferation, promotes production of other cytokines, enhances natural killer cell function, and is a cofactor for immunoglobulin secretion. SYN: T-cell growth factor.ABBR: IL-3
A cytokine produced by activated T cells that promotes proliferation of bone marrow stem cells. SYN: mast cell growth factor; multi-colony stimulating factor.ABBR: IL-4
A cytokine released by activated T cells and mast cells that stimulates B and T lymphocyte production and activity, prevents macrophages from releasing monokines, and promotes mast cell, immunoglobulin E, and eosinophil activity. SYN: B cell growth factor; mast cell growth factor II; T-cell growth factor II.ABBR: IL-5
A cytokine produced by T cells, eosinophils, and mast cells that acts as the primary stimulant for eosinophil production. SYN: eosinophil colony-stimulating factor; eosinophil differentiation factor.SEE: basophil(e); eosinophil.
ABBR: IL-6
A lymphokine produced by many cell types, including mononuclear phagocytes, T cells, and endothelial cells. It mediates the acute phase response, enhances B cell production and differentiation to immunoglobulin-secreting plasma cells, and stimulates megakaryocyte production. SYN: B-cell stimulatory factor-2; hepatocyte stimulatory factor.SEE: acute phase reaction; lymphokine.
ABBR: IL-7
A cytokine produced by the thymus, spleen, and bone marrow stromal cells. It stimulates growth of B-cell precursors, development of thymocytes, and activity of cytotoxic T-cells. SYN: lymphopoietin 1; pre-B cell growth factor.ABBR: IL-8
A cytokine produced by many cell types. It acts as a neutrophil chemoattractant.ABBR: IL-9
A cytokine produced by T cells. Among other functions, it promotes the proliferation and multiplication of mast cells.ABBR: IL-10
An anti-inflammatory cytokine derived from mononuclear phagocytes, T cells, and keratinocytes. It inhibits cytokine synthesis by macrophages, T cells, and natural killer cells, and enhances B cell growth and secretion of immunoglobulin.ABBR: IL-11
A cytokine produced by bone marrow stromal cells. It mediates acute phase protein synthesis, enhances B cell growth and differentiation to plasma cells, and promotes megakaryocyte production. SYN: plasmocytoma stimulating factor.ABBR: IL-12
A cytokine produced by mononuclear phagocytes and B cells. It induces interferon gamma production from T cells and natural killer cells, and enhances T cell and natural killer cell cytotoxicity. SYN: natural killer cell stimulating factor.ABBR: IL-13
A cytokine produced by T cells. It induces major histocompatibility class II expression on mononuclear phagocytes and B cells, proliferation of B cells, production of immunoglobulin, and regulates allergic responsiveness.ABBR: IL-14
A cytokine produced by T lymphocytes and follicular dendritic cells. It stimulates proliferation of activated B lymphocytes and inhibits immunoglobulin secretion from activated B lymphocytes.ABBR: IL-15
A cytokine released by epithelial cells in the kidney, skeletal muscle, liver, lungs, heart, and bone marrow, which stimulates production of T cells, esp. cytotoxic T cells and natural killer cells. It can bind with interleukin-2 receptors and mimic IL-2's effects.SEE: interleukin-2.
ABBR: IL-16
A cytokine produced by T lymphocytes that stimulates movement of monocytes, CD4+ T cells, and eosinophils to the area. It was previously known as lymphocyte chemoattractant factor.ABBR: IL-17
A cytokine produced by memory T lymphocytes that stimulates the proliferation of T cells and the differentiation of neutrophils. Drugs that inhibit IL-17 have been used to treat patients with ankylosing spondylitis and psoriatic arthritis.ABBR: IL-18
A proinflammatory cytokine produced by macrophages that stimulates the production of gamma interferon and other chemical mediators that enhance cell-mediated immune responses. It is similar in structure to IL-1.i.-23 A cytokine that promotes inflammatory responses in the body, e.g., the proliferation of certain T lymphocyte helper cells. It participates in several autoimmune processes.