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Interleukin
Interleukins (ILs) are a group of cytokines (secreted proteins and signal molecules) that are expressed and secreted by white blood cells (leukocytes) as well as some other body cells. The human genome encodes more than 50 interleukins and related proteins. The function of the immune system primarily depends on interleukins, and rare deficiencies of a number of them have been described, all featuring autoimmune diseases or immune deficiency. The majority of interleukins are synthesized by CD4 helper T-lymphocyte, as well as through monocytes, macrophages, and endothelial cells. They promote the development and differentiation of T and B lymphocytes, and hematopoietic cells. Interleukin receptors on astrocytes in the hippocampus are also known to be involved in the development of spatial memories in mice. History and name The name "interleukin" was chosen in 1979, to replace the various different names used by different research groups to designate interleukin 1 (lymphocyte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin 1
The Interleukin-1 family (IL-1 family) is a group of 11 cytokines that plays a central role in the regulation of immune and inflammatory responses to infections or sterile insults. Discovery Discovery of these cytokines began with studies on the pathogenesis of fever. The studies were performed by Eli Menkin and Paul Beeson in 1943–1948 on the fever-producing properties of proteins released from rabbit peritoneal exudate cells. These studies were followed by contributions of several investigators, who were primarily interested in the link between fever and infection/inflammation. The basis for the term "interleukin" was to streamline the growing number of biological properties attributed to soluble factors from macrophages and lymphocytes. IL-1 was the name given to the macrophage product, whereas IL-2 was used to define the lymphocyte product. At the time of the assignment of these names, there was no amino acid sequence analysis known and the terms were used to define bio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin 2
Interleukin-2 (IL-2) is an interleukin, a type of cytokine signaling molecule in the immune system. It is a 15.5–16 kDa protein that regulates the activities of white blood cells (leukocytes, often lymphocytes) that are responsible for immunity. IL-2 is part of the body's natural response to microbial infection, and in discriminating between foreign ("non-self") and "self". IL-2 mediates its effects by binding to IL-2 receptors, which are expressed by lymphocytes. The major sources of IL-2 are activated CD4+ T cells and activated CD8+ T cells. IL-2 receptor IL-2 is a member of a cytokine family, each member of which has a four alpha helix bundle; the family also includes IL-4, IL-7, IL-9, IL-15 and IL-21. IL-2 signals through the IL-2 receptor, a complex consisting of three chains, termed alpha (CD25), beta (CD122) and gamma ( CD132). The gamma chain is shared by all family members. The IL-2 receptor (IL-2R) α subunit binds IL-2 with low affinity (Kd~ 10 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IL1A
Interleukin-1 alpha (IL-1 alpha) also known as hematopoietin 1 is a cytokine of the interleukin 1 family that in humans is encoded by the ''IL1A'' gene. In general, Interleukin 1 is responsible for the production of inflammation, as well as the promotion of fever and sepsis. IL-1α inhibitors are being developed to interrupt those processes and treat diseases. IL-1α is produced mainly by activated macrophages, as well as neutrophils, epithelial cells, and endothelial cells. It possesses metabolic, physiological, haematopoietic activities, and plays one of the central roles in the regulation of the immune responses. It binds to the interleukin-1 receptor. It is on the pathway that activates tumor necrosis factor-alpha. Discovery Interleukin 1 was discovered by Gery in 1972. He named it lymphocyte-activating factor (LAF) because it was a lymphocyte mitogen. It was not until 1985 that interleukin 1 was discovered to consist of two distinct proteins, now called interleukin-1 alp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrophages
Macrophages (abbreviated as M φ, MΦ or MP) ( el, large eaters, from Greek ''μακρός'' (') = large, ''φαγεῖν'' (') = to eat) are a type of white blood cell of the immune system that engulfs and digests pathogens, such as cancer cells, microbes, cellular debris, and foreign substances, which do not have proteins that are specific to healthy body cells on their surface. The process is called phagocytosis, which acts to defend the host against infection and injury. These large phagocytes are found in essentially all tissues, where they patrol for potential pathogens by amoeboid movement. They take various forms (with various names) throughout the body (e.g., histiocytes, Kupffer cells, alveolar macrophages, microglia, and others), but all are part of the mononuclear phagocyte system. Besides phagocytosis, they play a critical role in nonspecific defense (innate immunity) and also help initiate specific defense mechanisms (adaptive immunity) by recruiting other immun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin 1 Receptor Antagonist
The interleukin-1 receptor antagonist protein (IL-1RN) is a protein that in humans is encoded by the ''IL1RN'' gene. IL-1RN was initially called the IL-1 inhibitor and was discovered separately in 1984 by two independent laboratories. IL-1RN is an agent that binds non-productively to the cell surface interleukin-1 receptor (IL-1R), the same receptor that binds interleukin 1 family (IL-1), preventing IL-1's from sending a signal to that cell. Function IL-1RA is a member of the interleukin 1 cytokine family. IL1Ra is secreted by various types of cells including immune cells, epithelial cells, and adipocytes, and is a natural inhibitor of the pro-inflammatory effect of IL1β. This protein inhibits the activities of interleukin 1, alpha (IL1A) and interleukin 1, beta (IL1B), and modulates a variety of interleukin 1 related immune and inflammatory responses. This gene and five other closely related cytokine genes form a gene cluster spanning approximately 400 kb on chromosome 2. Fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD4 Helper T-lymphocyte
The T helper cells (Th cells), also known as CD4+ cells or CD4-positive cells, are a type of T cell that play an important role in the adaptive immune system. They aid the activity of other immune cells by releasing cytokines. They are considered essential in B cell Immunoglobulin class switching, antibody class switching, breaking Cross-presentation, cross-tolerance in dendritic cells, in the activation and growth of cytotoxic T cells, and in maximizing bactericidal activity of phagocytes such as macrophages and neutrophils. CD4+ cells are mature Th cells that express the surface protein CD4. Genetic variation in regulatory elements expressed by CD4+ cells determines susceptibility to a broad class of autoimmune diseases. Structure and function Th cells contain and release cytokines to aid other immune cells. Cytokines are small protein mediators that alter the behavior of target cells that express Receptor (biochemistry), receptors for those cytokines. These cells help polar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin 1 Receptor, Type II
Interleukin 1 receptor, type II (IL-1R2) also known as CD121b (Cluster of Differentiation 121b) is an interleukin receptor. IL1R2 also denotes its human gene. Function The protein encoded by this gene is a decoy receptor for certain cytokines that belongs to the interleukin-1 receptor family. This protein binds interleukin-1α (IL1A), interleukin-1β (IL1B), and interleukin 1 receptor antagonist (IL1Ra), preventing them from binding to their regular receptors and thereby inhibiting the transduction of their signaling. IL-1R2 protein also interacts non-productively with the second component of the signaling IL-1 receptor, namely IL-1RAcP, and a complex of the IL-1R2 and IL-1RAcP extracellular domains with interleukin-1 beta has been solved by X-ray crystallography. Interleukin 4 (IL4) is reported to antagonize the activity of interleukin 1 by inducing the expression and release of this cytokine. This gene and three other genes form a cytokine receptor gene cluster on chromosome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytokine
Cytokines are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrine, paracrine and endocrine signaling as immunomodulating agents. Cytokines include chemokines, interferons, interleukins, lymphokines, and tumour necrosis factors, but generally not hormones or growth factors (despite some overlap in the terminology). Cytokines are produced by a broad range of cells, including immune cells like macrophages, B lymphocytes, T lymphocytes and mast cells, as well as endothelial cells, fibroblasts, and various stromal cells; a given cytokine may be produced by more than one type of cell. They act through cell surface receptors and are especially important in the immune system; cytokines modulate the balance between humoral and cell-based immune responses, and they regulate the maturation, growth, and res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IL1B
Interleukin-1 beta (IL-1β) also known as leukocytic pyrogen, leukocytic endogenous mediator, mononuclear cell factor, lymphocyte activating factor and other names, is a cytokine protein that in humans is encoded by the ''IL1B'' gene."Catabolin" is the name given by Jeremy Saklatvala for IL-1 alpha. There are two genes for interleukin-1 (IL-1): IL-1 alpha and IL-1 beta (this gene). IL-1β precursor is cleaved by cytosolic caspase 1 (interleukin 1 beta convertase) to form mature IL-1β. Function The fever-producing property of human leukocytic pyrogen (interleukin 1) was purified by Dinarello in 1977 with a specific activity of 10–20 nanograms/kg. In 1979, Dinarello reported that purified human leukocytic pyrogen was the same molecule that was described by Igal Gery in 1972. He named it lymphocyte-activating factor (LAF) because it was a lymphocyte mitogen. It was not until 1984 that interleukin 1 was discovered to consist of two distinct proteins, now called interleukin-1 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin 1 Receptor, Type I
Interleukin 1 receptor, type I (IL1R1) also known as CD121a (Cluster of Differentiation 121a), is an interleukin receptor. IL1R1 also denotes its human gene. The protein encoded by this gene is a cytokine receptor that belongs to the interleukin-1 receptor family. This protein is a receptor for interleukin 1 alpha (IL1A), interleukin 1 beta (IL1B), and interleukin 1 receptor antagonist (IL1RA). It is an important mediator involved in many cytokine induced immune and inflammatory responses. This gene along with interleukin 1 receptor, type II (IL1R2), interleukin 1 receptor-like 2 (IL1RL2), and interleukin 1 receptor-like 1 (IL1RL1) form a cytokine receptor gene cluster in a region mapped to chromosome 2q12. Interactions Interleukin 1 receptor, type I has been shown to interact with PIK3R1, Myd88 and IL1RAP. See also * Cluster of differentiation * Interleukin 1 receptor, type II Interleukin 1 receptor, type II (IL-1R2) also known as CD121b (Cluster of Differentiation 121b) is an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hematopoietic
Haematopoiesis (, from Greek , 'blood' and 'to make'; also hematopoiesis in American English; sometimes also h(a)emopoiesis) is the formation of blood cellular components. All cellular blood components are derived from haematopoietic stem cells. In a healthy adult person, approximately – new blood cells are produced daily in order to maintain steady state levels in the peripheral circulation.Semester 4 medical lectures at Uppsala University 2008 by Leif Jansson Process Haematopoietic stem cells (HSCs) Haematopoietic stem cells (HSCs) reside in the medulla of the bone (bone marrow) and have the unique ability to give rise to all of the different mature blood cell types and tissues. HSCs are self-renewing cells: when they differentiate, at least some of their daughter cells remain as HSCs so the pool of stem cells is not depleted. This phenomenon is called asymmetric division. The other daughters of HSCs ( myeloid and lymphoid progenitor cells) can follow any of the other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphokine
Lymphokines are a subset of cytokines that are produced by a type of immune cell known as a lymphocyte. They are protein mediators typically produced by T cells to direct the immune system response by signaling between its cells. Lymphokines have many roles, including the attraction of other immune cells, including macrophages and other lymphocytes, to an infected site and their subsequent activation to prepare them to mount an immune response. Circulating lymphocytes can detect a very small concentration of lymphokine and then move up the concentration gradient towards where the immune response is required. Lymphokines aid B cells to produce antibodies. Important lymphokines secreted by the T helper cell include:Guyton, AC; Hall, JE. (2006) Medical Physiology, Elsevier Saunders. 11th edition, pp.447. * Interleukin 2 * Interleukin 3 * Interleukin 4 * Interleukin 5 * Interleukin 6 * Granulocyte-macrophage colony-stimulating factor * Interferon-gamma Interferon gamma (IFN-γ) is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
