Immune-mediated inflammatory diseases

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An immune-mediated inflammatory disease (IMID) is any of a group of conditions or diseases that lack a definitive etiology, but which are characterized by common inflammatory pathways leading to inflammation, and which may result from, or be triggered by, a dysregulation of the normal immune response. All IMIDs can cause end organ damage, and are associated with increased morbidity and/or mortality.

Contents

Inflammation is an important and growing area of biomedical research and health care because inflammation mediates and is the primary driver of many medical disorders and autoimmune diseases, including ankylosing spondylitis, psoriasis, psoriatic arthritis, Behçet's disease, arthritis, inflammatory bowel disease (IBD), and allergy, as well as many cardiovascular, neuromuscular, and infectious diseases. Some current research even suggests that aging is a consequence, in part, of inflammatory processes.

Characterization

IMID is characterized by immune disregulation, and one underlying manifestation of this immune disregulation is the inappropriate activation of inflammatory cytokines, such as IL-12, IL-6 or TNF alpha, whose actions lead to pathological consequences.

See also

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Related Research Articles

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<span class="mw-page-title-main">Autoimmunity</span> Immune response against an organisms own healthy cells

In immunology, autoimmunity is the system of immune responses of an organism against its own healthy cells, tissues and other normal body constituents. Any disease resulting from this type of immune response is termed an "autoimmune disease". Prominent examples include celiac disease, post-infectious IBS, diabetes mellitus type 1, Henoch–Schönlein purpura (HSP) sarcoidosis, systemic lupus erythematosus (SLE), Sjögren syndrome, eosinophilic granulomatosis with polyangiitis, Hashimoto's thyroiditis, Graves' disease, idiopathic thrombocytopenic purpura, Addison's disease, rheumatoid arthritis (RA), ankylosing spondylitis, polymyositis (PM), dermatomyositis (DM), Alopecia Areata and multiple sclerosis (MS). Autoimmune diseases are very often treated with steroids.

Psychoneuroimmunology (PNI), also referred to as psychoendoneuroimmunology (PENI) or psychoneuroendocrinoimmunology (PNEI), is the study of the interaction between psychological processes and the nervous and immune systems of the human body. It is a subfield of psychosomatic medicine. PNI takes an interdisciplinary approach, incorporating psychology, neuroscience, immunology, physiology, genetics, pharmacology, molecular biology, psychiatry, behavioral medicine, infectious diseases, endocrinology, and rheumatology.

<span class="mw-page-title-main">Uveitis</span> Inflammation of the uvea of the eye

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<span class="mw-page-title-main">Interleukin 13</span> Protein and coding gene in humans

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<span class="mw-page-title-main">Biological therapy for inflammatory bowel disease</span>

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<span class="mw-page-title-main">Interleukin 17</span> Group of proteins

Interleukin 17 family is a family of pro-inflammatory cystine knot cytokines. They are produced by a group of T helper cell known as T helper 17 cell in response to their stimulation with IL-23. Originally, Th17 was identified in 1993 by Rouvier et al. who isolated IL17A transcript from a rodent T-cell hybridoma. The protein encoded by IL17A is a founding member of IL-17 family. IL17A protein exhibits a high homology with a viral IL-17-like protein encoded in the genome of T-lymphotropic rhadinovirus Herpesvirus saimiri. In rodents, IL-17A is often referred to as CTLA8.

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<span class="mw-page-title-main">IL17A</span> Protein-coding gene in the species Homo sapiens

Interleukin-17A is a protein that in humans is encoded by the IL17A gene. In rodents, IL-17A used to be referred to as CTLA8, after the similarity with a viral gene.

Damage-associated molecular patterns (DAMPs) are molecules within cells that are a component of the innate immune response released from damaged or dying cells due to trauma or an infection by a pathogen. They are also known as danger-associated molecular patterns, danger signals, and alarmin because they serve as a warning sign for the organism to alert it of any damage or infection to its cells. DAMPs are endogenous danger signals that are discharged to the extracellular space in response to damage to the cell from trauma or pathogen. Once a DAMP is released from the cell, it promotes a noninfectious inflammatory response by binding to a pattern-recognition receptor. Inflammation is a key aspect of the innate immune response because it is used to help mitigate future damage to the organism by removing harmful invaders from the affected area and start the healing process. As an example, the cytokine IL-1α is a DAMP that originates within the nucleus of the cell, which once released to the extracellular space, binds to the PRR IL-1R, which in turn initiates an inflammatory response to the trauma or pathogen that initiated the release of IL-1α. In contrast to the noninfectious inflammatory response produced by DAMPs, pathogen-associated molecular patterns initiate and perpetuate the infectious pathogen-induced inflammatory response. Many DAMPs are nuclear or cytosolic proteins with defined intracellular function that are released outside the cell following tissue injury. This displacement from the intracellular space to the extracellular space moves the DAMPs from a reducing to an oxidizing environment, causing their functional denaturation, resulting in their loss of function. Outside of the aforementioned nuclear and cytosolic DAMPs, there are other DAMPs originated from different sources, such as mitochondria, granules, the extracellular matrix, the endoplasmic reticulum, and the plasma membrane.

<span class="mw-page-title-main">Autoimmune disease</span> Abnormal immune response to a normal body part

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<span class="mw-page-title-main">Interleukin 23</span> Heterodimeric cytokine acting as mediator of inflammation

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<span class="mw-page-title-main">Type 3 innate lymphoid cells</span>

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<span class="mw-page-title-main">Inflammaging</span> Chronic low-grade inflammation that develops with advanced age

Inflammaging is a chronic, sterile low-grade inflammation that develops with advanced age, in the absence of overt infection, and may contribute to clinical manifestations of other age-related pathologies. Inflammaging is thought to be caused by a loss of control over systemic inflammation resulting in chronic, overstimulation of the innate immune system. Inflammaging is a significant risk factor in mortality and morbidity in aged individuals

Autoinflammatory diseases (AIDs) are a group of rare disorders caused by dysfunction of the innate immune system. They are characterized by periodic or chronic systemic inflammation usually without the involvement of adaptive immunity.

<span class="mw-page-title-main">Interleukin 17F</span>

Interleukin 17F (IL-17F) is signaling protein that is in human is encoded by the IL17F gene and is considered a pro-inflammatory cytokine. This protein belongs to the interleukin 17 family and is mainly produced by the T helper 17 cells after their stimulation with interleukin 23. However, IL-17F can be also produced by a wide range of cell types, including innate immune cells and epithelial cells.

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