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ILC3
Type 3 innate lymphoid cells (ILC3) are immune cells from the lymphoid lineage that are part of the innate immune system. These cells participate in innate mechanisms on mucous membranes, contributing to tissue homeostasis, host-commensal mutualism and pathogen clearance. They are part of a heterogeneous group of innate lymphoid cells, which is traditionally divided into three subsets based on their expression of master transcription factors as well as secreted effector cytokines - ILC1, ILC2 and ILC3. Characterization ILC 3 family can be divided into two subgroups based on their expression of natural cytotoxicity receptors (NCRs), designated NCR+ ILC3 and NCR− ILC3. These receptors are commonly found on natural killer cells and some subpopulations of innate and adaptive cells. They are involved in activation and cytotoxic activity of NK cells, including cells lysis and secretion of pro-inflammatory cytokines. LTi cells (lymphoid tissue-inducing cells) are a subpopulation impor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Innate Lymphoid Cell
Innate lymphoid cells (ILCs) are the most recently discovered family of innate immune cells, derived from common lymphoid progenitors (CLPs). In response to pathogenic tissue damage, ILCs contribute to immunity via the secretion of signalling molecules, and the regulation of both innate and adaptive immune cells. ILCs are primarily tissue resident cells, found in both lymphoid (immune associated), and non- lymphoid tissues, and rarely in the blood. They are particularly abundant at mucosal surfaces, playing a key role in mucosal immunity and homeostasis. Characteristics allowing their differentiation from other immune cells include the regular lymphoid morphology, absence of rearranged antigen receptors found on T cells and B cells (due to the lack of the RAG gene), and phenotypic markers usually present on myeloid or dendritic cells. Based on the difference in developmental pathways, phenotype, and signalling molecules produced, in 2013, ILCs were divided into three groups: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RAR-related Orphan Receptor Gamma
RAR-related orphan receptor gamma (RORγ) is a protein that in humans is encoded by the ''RORC'' ( RAR-related orphan receptor C) gene. RORγ is a member of the nuclear receptor family of transcription factors. It is mainly expressed in immune cells (Th17 cells) and it also regulates circadian rhythms. It may be involved in the progression of certain types of cancer. Gene expression Two isoforms are produced from the same ''RORC'' gene, probably by selection of alternative promoters. * RORγ (also referred to as RORγ1) – produced from an mRNA containing exons 1 to 11. * RORγt (also known as RORγ2) – produced from an mRNA identical to that of RORγ, except that the two 5'-most exons are replaced by an alternative exon, located downstream in the gene. This causes a different, shorter N-terminus. RORγ The mRNA of the first isoform, RORγ is expressed in many tissues, including thymus, lung, liver, kidney, muscle, and brown fat. While RORγ mRNA is abundantly expressed, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin 23
Interleukin 23 (IL-23) is a heterodimeric cytokine composed of an IL-12B (IL-12p40) subunit (which is shared with IL-12) and an IL-23A (IL-23p19) subunit. IL-23 is part of the IL-12 family of cytokines. The functional receptor for IL-23 (the IL-23 receptor) consists of a heterodimer between IL-12Rβ1 and IL-23R. Discovery IL-23 was first described by Robert Kastelein and colleagues at the DNAX research institute using a combination of computational, biochemical and cellular immunology approaches. Function IL-23 is an inflammatory cytokine. It has been shown to be a key cytokine for T helper type 17 cell (Th17 cell) maintenance and expansion. Polarisation to a Th17 phenotype is triggered by IL-6 and TGF-β, which activate the Th17 transcription factor RORγt. IL-23 stabilises RORγt and thus enables Th17 cells to release their effector cytokines, such as IL-17, IL-21, IL-22 and GM-CSF, which mediate protection against extracellular fungi and bacteria and parti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin 22
Interleukin-22 (IL-22) is protein that in humans is encoded by the ''IL22'' gene. Structure IL-22 is an α-helical cytokine. IL-22 binds to a heterodimeric cell surface receptor composed of IL-10R2 and IL-22R1 subunits. IL-22R is expressed on tissue cells, and it is absent on immune cells. Crystallization is possible if the N-linked glycosylation sites are removed in mutants of IL-22 bound with high-affinity cell-surface receptor sIL-22R1. The crystallographic asymmetric unit contained two IL-22-sIL-22R1 complexes. Function IL-22 is produced by several populations of immune cells at a site of inflammation. Producers are αβ T cells classes Th1, Th22 and Th17 along with γδ T cells, NKT, ILC3, neutrophils and macrophages. IL-22 takes effect on non-hematopoietic cells – mainly stromal and epithelial cells. Effects involve stimulation of cell survival, proliferation and synthesis of antimicrobials including S100, Reg3β, Reg3γ and defensins. IL-22 thus participates ... [...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] |
Beta Defensin
Beta defensins are a family of vertebrate defensins. The beta defensins are antimicrobial peptides implicated in the resistance of epithelial surfaces to microbial colonization. Defensins are 2-6 kDa, cationic, microbicidal peptides active against many Gram-negative and Gram-positive bacteria, fungi, and enveloped viruses, containing three pairs of intramolecular disulfide bonds. On the basis of their size and pattern of disulfide bonding, mammalian defensins are classified into alpha, beta and theta categories. Every mammalian species explored thus far has beta-defensins. In cows, as many as 13 beta-defensins exist in neutrophils. However, in other species, beta-defensins are more often produced by epithelial cells lining various organs (e.g. the epidermis, bronchial tree and genitourinary tract. Human, rabbit and guinea-pig beta-defensins, as well as human beta-defensin-2 (hBD2), induce the activation and degranulation of mast cells, resulting in the release of histamine and pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutaneous Condition
A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment. Conditions of the human integumentary system constitute a broad spectrum of diseases, also known as dermatoses, as well as many nonpathologic states (like, in certain circumstances, melanonychia and racquet nails). While only a small number of skin diseases account for most visits to the physician, thousands of skin conditions have been described. Classification of these conditions often presents many nosological challenges, since underlying causes and pathogenetics are often not known. Therefore, most current textbooks present a classification based on location (for example, conditions of the mucous membrane), morphology ( chronic blistering conditions), cause (skin conditions result ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psoriasis
Psoriasis is a long-lasting, noncontagious autoimmune disease characterized by raised areas of abnormal skin. These areas are red, pink, or purple, dry, itchy, and scaly. Psoriasis varies in severity from small, localized patches to complete body coverage. Injury to the skin can trigger psoriatic skin changes at that spot, which is known as the Koebner phenomenon. The five main types of psoriasis are plaque, guttate, inverse, pustular, and erythrodermic. Plaque psoriasis, also known as psoriasis vulgaris, makes up about 90% of cases. It typically presents as red patches with white scales on top. Areas of the body most commonly affected are the back of the forearms, shins, navel area, and scalp. Guttate psoriasis has drop-shaped lesions. Pustular psoriasis presents as small, noninfectious, pus-filled blisters. Inverse psoriasis forms red patches in skin folds. Erythrodermic psoriasis occurs when the rash becomes very widespread, and can develop from any of the other types. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MHC Class II
MHC Class II molecules are a class of major histocompatibility complex (MHC) molecules normally found only on professional antigen-presenting cells such as dendritic cells, mononuclear phagocytes, some endothelial cells, thymic epithelial cells, and B cells. These cells are important in initiating immune responses. The antigens presented by class II peptides are derived from extracellular proteins (not cytosolic as in MHC class I). Loading of a MHC class II molecule occurs by phagocytosis; extracellular proteins are endocytosed, digested in lysosomes, and the resulting epitopic peptide fragments are loaded onto MHC class II molecules prior to their migration to the cell surface. In humans, the MHC class II protein complex is encoded by the human leukocyte antigen gene complex (HLA). HLAs corresponding to MHC class II are HLA-DP, HLA-DM, HLA-DOA, HLA-DOB, HLA-DQ, and HLA-DR. Mutations in the HLA gene complex can lead to bare lymphocyte syndrome (BLS), which is a type of MHC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mucin
Mucins () are a family of high molecular weight, heavily glycosylated proteins (glycoconjugates) produced by epithelial tissues in most animals. Mucins' key characteristic is their ability to form gels; therefore they are a key component in most gel-like secretions, serving functions from lubrication to cell signalling to forming chemical barriers. They often take an inhibitory role. Some mucins are associated with controlling mineralization, including nacre formation in mollusks, calcification in echinoderms and bone formation in vertebrates. They bind to pathogens as part of the immune system. Overexpression of the mucin proteins, especially MUC1, is associated with many types of cancer. Although some mucins are membrane-bound due to the presence of a hydrophobic membrane-spanning domain that favors retention in the plasma membrane, most mucins are secreted as principal components of mucus by mucous membranes or are secreted to become a component of saliva. Genes Human muci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clonal Anergy
In immunology, anergy is a lack of reaction by the body's defense mechanisms to foreign substances, and consists of a direct induction of peripheral lymphocyte tolerance. An individual in a state of anergy often indicates that the immune system is unable to mount a normal immune response against a specific antigen, usually a self-antigen. Lymphocytes are said to be ''anergic'' when they fail to respond to their specific antigen. Anergy is one of three processes that induce tolerance, modifying the immune system to prevent self-destruction (the others being clonal deletion and immunoregulation). Mechanism This phenomenon was first described in B lymphocytes by Gustav Nossal and termed "clonal anergy." The clones of B lymphocytes in this case can still be found alive in the circulation, but are ineffective at mounting immune responses. Later Ronald Schwartz and Marc Jenkins described a similar process operating in the T lymphocyte. Many viruses (HIV being the most extreme examp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
