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Lipoarabinomannan
Lipoarabinomannan, also called LAM, is a glycolipid, and a virulence factor associated with ''Mycobacterium tuberculosis'', the bacteria responsible for tuberculosis. Its primary function is to inactivate macrophages and scavenge oxidative radicals. The inactivation of macrophages allows for the dissemination of mycobacteria to other parts of the body. The destruction of oxidative radicals allows for the survival of the bacteria, as oxidative free radicals are an important mechanism by which our bodies try to rid ourselves of infection. Background Lipoarabinomannan is a lipoglycan and major virulence factor in the bacteria genus ''Mycobacterium''. In addition to serving as a major cell wall component, it is thought to serve as a modulin with immunoregulatory and anti-inflammatory effects. This allows the bacterium to maintain survival in the human reservoir by undermining host resistance and acquired immune responses. These mechanisms include the inhibition of T-cell proliferati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipomannan
Lipomannan is a mycobacterium immune agonist. In addition, it is a major constituent of the mycobacterium cell wall. This glycoconjugate is a virulence factor that plays a key role in the human immune system via interaction with various immune cells. It is also considered to be a precursor of Lipoarabinomannan, lipoarabinomannans. It is a trigger for TLR 2. It consists of an α-linked mannan, which consists of 50–70 residues, with some branches points linked glycosidically to a diglyceride of which the fatty acids are similar to those of the whole cell lipid. In addition, succinic acid residues are present as O-acyl substituent, O-acyl substituents on about one in four of the mannose residues, the terminal Carboxyl Group, carboxyl group of the succinic acid providing the whole polymer with a considerable number of acidic functions. Lipomannan has functional components that resemble Lipoteichoic acid, lipoteichoic acids; a lipophilic region and a hydrophilic portion with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycolipid
Glycolipids () are lipids with a carbohydrate attached by a glycosidic (covalent) bond. Their role is to maintain the stability of the cell membrane and to facilitate cellular recognition, which is crucial to the immune response and in the connections that allow cells to connect to one another to form tissues. Glycolipids are found on the surface of all eukaryotic cell membranes, where they extend from the phospholipid bilayer into the extracellular environment. Structure The essential feature of a glycolipid is the presence of a monosaccharide or oligosaccharide bound to a lipid moiety. The most common lipids in cellular membranes are glycerolipids and sphingolipids, which have glycerol or a sphingosine backbones, respectively. Fatty acids are connected to this backbone, so that the lipid as a whole has a polar head and a non-polar tail. The lipid bilayer of the cell membrane consists of two layers of lipids, with the inner and outer surfaces of the membrane made up o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycobacterium Bovis
''Mycobacterium bovis'' is a slow-growing (16- to 20-hour generation time) Aerobic organism, aerobic bacterium and the causative agent of tuberculosis in cattle (known as bovine TB). It is related to ''Mycobacterium tuberculosis'', the bacterium which causes tuberculosis in humans. ''M. bovis'' can zoonosis, jump the species barrier and cause tuberculosis-like infection in humans and other mammals. Bacterium morphology and staining The bacteria are curved or straight rods. They sometimes form filaments, which fragment into Bacillus (shape), bacilli or coccus, cocci once disturbed. In tissues, they form slender rods, straight or curved, or club-shaped. Short, relatively plump bacilli (rods) are seen in tissue smears, and large slender beaded rods in culture. They have no Flagellum, flagella or Fimbria (bacteriology), fimbria, and no Bacterial capsule, capsule. ''Mycobacterium tuberculosis'' group bacteria are 1.0-4.0 μm long by 0.2-0.3 μm wide in tissues. In cultur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycobacterium Chelonae
''Mycobacteroides chelonae'' (formerly ''Mycobacterium chelonae'') is a species of bacteria from the phylum Actinomycetota belonging to the genus '' Mycobacteroides''. ''Mycobacteroides chelonae'' is a rapidly growing mycobacterium that is found all throughout the environment, including sewage and tap water. It can occasionally cause opportunistic infections of humans. It is grouped in Runyon group IV. The complete genome sequence of the ''M. chelonae'' CCUG 47445 type strain was deposited and published in DNA Data Bank of Japan, European Nucleotide Archive, and GenBank The GenBank sequence database is an open access, annotated collection of all publicly available nucleotide sequences and their protein translations. It is produced and maintained by the National Center for Biotechnology Information (NCBI; a par ... in 2016 under the accession numbeCP007220 Epidemiology On average, two cases of nonpulmonary ''M. chelonae'' infection are reported in South Australia each year. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toll-like Receptor 2
Toll-like receptor 2 also known as TLR2 is a protein that in humans is encoded by the ''TLR2'' gene. TLR2 has also been designated as CD282 (cluster of differentiation 282). TLR2 is one of the toll-like receptors and plays a role in the immune system. TLR2 is a membrane protein, a receptor, which is expressed on the surface of certain cells and recognizes foreign substances and passes on appropriate signals to the cells of the immune system. Function The protein encoded by this gene is a member of the toll-like receptor (TLR) family, which plays a fundamental role in pathogen recognition and activation of innate immunity. TLRs are highly conserved from ''Drosophila'' to humans and share structural and functional similarities. They recognize pathogen-associated molecular patterns (PAMPs) that are expressed on infectious agents, and mediate the production of cytokines necessary for the development of effective immunity. The various TLRs exhibit different patterns of expression. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD14
CD14 ( cluster of differentiation 14) is a human protein made mostly by macrophages as part of the innate immune system. It helps to detect bacteria in the body by binding lipopolysaccharide (LPS), a pathogen-associated molecular pattern (PAMP). CD14 exists in two forms, one anchored to the membrane by a glycosylphosphatidylinositol (GPI) tail (mCD14), the other a soluble form (sCD14). Soluble CD14 either appears after shedding of mCD14 (48 kDa) or is directly secreted from intracellular vesicles (56 kDa). The x-ray crystal structure of human CD14 reveals a monomeric, bent solenoid structure containing a hydrophobic amino-terminal pocket. CD14 was the first described pattern recognition receptor. Function CD14 acts as a co-receptor (along with the Toll-like receptor TLR 4 and MD-2) for the detection of bacterial lipopolysaccharide (LPS). CD14 can bind LPS only in the presence of lipopolysaccharide-binding protein (LBP). Although LPS is considered its main ligand, CD14 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRAF6
TRAF6 is a TRAF human protein. Function The protein encoded by this gene is a member of the TNF receptor associated factor (TRAF) protein family. TRAF proteins are associated with, and mediate signal transduction from members of the TNF receptor superfamily. This protein mediates the signaling not only from the members of the TNF receptor superfamily, but also from the members of the Toll/IL-1 family. Signals from receptors such as CD40, TNFSF11/TRANCE/RANKL and IL-1 have been shown to be mediated by this protein. This protein also interacts with various protein kinases including IRAK1/IRAK, SRC and PKCzeta, which provides a link between distinct signaling pathways. This protein functions as a signal transducer in the NF-kappaB pathway that activates IkappaB kinase (IKK) in response to proinflammatory cytokines. The interaction of this protein with UBE2N/UBC13, and UBE2V1/UEV1A, which are ubiquitin conjugating enzymes catalyzing the formation of polyubiquitin chains, has be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IRAK
The interleukin-1 receptor (IL-1R) associated kinase (IRAK) family plays a crucial role in the protective response to pathogens introduced into the human body by inducing acute inflammation followed by additional adaptive immune responses. IRAKs are essential components of the Interleukin-1 receptor signaling pathway and some Toll-like receptor signaling pathways. Toll-like receptors (TLRs) detect microorganisms by recognizing specific pathogen-associated molecular patterns (PAMPs) and IL-1R family members respond the interleukin-1 (IL-1) family cytokines. These receptors initiate an intracellular signaling cascade through adaptor proteins, primarily, MyD88.Suzuki, N., Suzuki, S., and Saito, T. 2005. IRAKs: Key Regulatory Kinases of Innate Immunity. Curr. Med. Chem. – Anti-Inflammatory & Anti-Allergy Agents, 4(1), 13-20. This is followed by the activation of IRAKs. TLRs and IL-1R members have a highly conserved amino acid sequence in their cytoplasmic domain called the Toll/Interle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Killer Cell
Natural killer cells, also known as NK cells, are a type of cytotoxic lymphocyte critical to the innate immune system. They are a kind of large granular lymphocytes (LGL), and belong to the rapidly expanding family of known innate lymphoid cells (ILC) and represent 5–20% of all circulating lymphocytes in humans. The role of NK cells is analogous to that of cytotoxic T cells in the vertebrate adaptive immune response. NK cells provide rapid responses to virus-infected cells, stressed cells, tumor cells, and other intracellular pathogens based on signals from several activating and inhibitory receptors. Most immune cells detect the antigen presented on MHC class I, major histocompatibility complex I (MHC-I) on infected cell surfaces, but NK cells can recognize and kill stressed cells in the absence of antibodies and MHC, allowing for a much faster immune reaction. They were named "natural killers" because of the notion that they do not require activation to kill cells that are m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granuloma
A granuloma is an aggregation of macrophages (along with other cells) that forms in response to chronic inflammation. This occurs when the immune system attempts to isolate foreign substances that it is otherwise unable to eliminate. Such substances include infectious organisms including bacteria and fungi, as well as other materials such as foreign objects, keratin, and suture fragments. Definition In pathology, a granuloma is an organized collection of macrophages. In medical practice, doctors occasionally use the term ''granuloma'' in its more literal meaning: "a small nodule". Since a small nodule can represent any tissue from a harmless nevus to a malignant tumor, this use of the term is not very specific. Examples of this use of the term ''granuloma'' are the lesions known as vocal cord granuloma (known as contact granuloma), pyogenic granuloma, and intubation granuloma, all of which are examples of granulation tissue, not granulomas. "Pulmonary hyalinizing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipopolysaccharide
Lipopolysaccharide (LPS), now more commonly known as endotoxin, is a collective term for components of the outermost membrane of the cell envelope of gram-negative bacteria, such as '' E. coli'' and ''Salmonella'' with a common structural architecture. Lipopolysaccharides are large molecules consisting of three parts: an outer core polysaccharide termed the O-antigen, an inner core oligosaccharide and Lipid A (from which toxicity is largely derived), all covalently linked. In current terminology, the term endotoxin is often used synonymously with LPS, although there are a few endotoxins (in the original sense of toxins that are inside the bacterial cell that are released when the cell disintegrates) that are not related to LPS, such as the so-called delta endotoxin proteins produced by '' Bacillus thuringiensis''. Lipopolysaccharides can have substantial impacts on human health, primarily through interactions with the immune system. LPS is a potent activator of the immune syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
