HLA-DR Haplotypes

	HLA-DR Haplotypes HLA-DR is an MHC class II cell surface receptor encoded by the human leukocyte antigen complex on chromosome 6 region 6p21.31. The complex of HLA-DR (Human Leukocyte Antigen – DR isotype) and peptide, generally between 9 and 30 amino acids in length, constitutes a ligand for the T-cell receptor (TCR). HLA (human leukocyte antigens) were originally defined as cell surface antigens that mediate graft-versus-host disease. Identification of these antigens has led to greater success and longevity in organ transplant. Antigens most responsible for graft loss are HLA-DR (first six months), HLA-B (first two years), and HLA-A (long-term survival). Good matching of these antigens between host and donor is most critical for achieving graft survival. HLA-DR is also involved in several autoimmune conditions, disease susceptibility and disease resistance. It is also closely linked to HLA-DQ and this linkage often makes it difficult to resolve the more causative factor in disease. HLA-DR mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	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]
picture info	Antigen-presenting Cell An antigen-presenting cell (APC) or accessory cell is a cell that displays antigen bound by major histocompatibility complex (MHC) proteins on its surface; this process is known as antigen presentation. T cells may recognize these complexes using their T cell receptors (TCRs). APCs process antigens and present them to T-cells. Almost all cell types can present antigens in some way. They are found in a variety of tissue types. Professional antigen-presenting cells, including macrophages, B cells and dendritic cells, present foreign antigens to helper T cells, while virus-infected cells (or cancer cells) can present antigens originating inside the cell to cytotoxic T cells. In addition to the MHC family of proteins, antigen presentation relies on other specialized signaling molecules on the surfaces of both APCs and T cells. Antigen-presenting cells are vital for effective adaptive immune response, as the functioning of both cytotoxic and helper T cells is dependent on APCs. Antigen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Gene Conversion Gene conversion is the process by which one DNA sequence replaces a homologous sequence such that the sequences become identical after the conversion event. Gene conversion can be either allelic, meaning that one allele of the same gene replaces another allele, or ectopic, meaning that one paralogous DNA sequence converts another. Allelic gene conversion Allelic gene conversion occurs during meiosis when homologous recombination between heterozygotic sites results in a mismatch in base pairing. This mismatch is then recognized and corrected by the cellular machinery causing one of the alleles to be converted to the other. This can cause non-Mendelian segregation of alleles in germ cells. Nonallelic/ectopic gene conversion Recombination occurs not only during meiosis, but also as a mechanism for repair of double-strand breaks (DSBs) caused by DNA damage. These DSBs are usually repaired using the sister chromatid of the broken duplex and not the homologous chromosome, so they wou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	HLA DR3-DQ2 HLA DR3-DQ2 is double serotype that specifically recognizes cells from individuals who carry a multigene HLA DR, DQ haplotype. Certain HLA DR and DQ genes have known involvement in autoimmune diseases. DR3- DQ2, a multigene haplotype, stands out in prominence because it is a factor in several prominent diseases, namely coeliac disease and juvenile diabetes. In coeliac disease, the DR3-DQ2 haplotype is associated with highest risk for disease in first degree relatives, highest risk is conferred by DQA10501:DQB10201 homozygotes and semihomozygotes of DQ2, and represents the overwhelming majority of risk. HLA DR3-DQ2 encodes DQ2.5cis isoform of HLA-DQ, this isoform is described frequently as 'the DQ2 isoform', but in actuality there are two major DQ2 isoform. The DQ2.5 isoform, however, is many times more frequently associated with autoimmune disease, and as a result to contribution of DQ2.2 is often ignored. The frequency of both diseases changes with respect to both the envi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	HLA-DR2 HLA-DR2 (DR2) of the HLA- DR serotype system, is a broad antigen serotype that is now preferentially covered by HLA-DR15 and HLA-DR16 serotype group. This serotype primarily recognizes gene products of the HLA-DRB115 and HLA-DRB116 allele groups. Serology Disease associations DR2 serotypes are associated with Goodpasture syndrome, systemic lupus erythematosus, multiple sclerosis, and narcolepsy, tuberculoid leprosy (multi-drug-resistant tuberculosis or leprosy), ulcerative colitis(Japanese), primary biliary cirrhosis and autoimmune hepatitis. DR2 is also found in all patients that test positive for anti-anti-Asn-RNA-synthetase and chronic interstitial lung disease. Genetic linkage DR2 is linked to the HLA-DR51 HLA-DR51 is a HLA-DR serotype that recognizes the antigens encoded by the minor DR locus HLA-DRB5. DRB3, DRB4, and DRB5 are minor DR beta encoding loci, they have been recognized as having distinct evolution, having diverged from DRB1 approximate .... Reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	HLA-DR51 HLA-DR51 is a HLA-DR serotype that recognizes the antigens encoded by the minor DR locus HLA-DRB5. DRB3, DRB4, and DRB5 are minor DR beta encoding loci, they have been recognized as having distinct evolution, having diverged from DRB1 approximately 4 million years ago. DRB5 locus is only apparent in a small subset of DR haplotypes, and most individuals lack DRB5. Alleles DRB5* is subdivided into two allele groups, DRB501 and DRB502. B501 encodes 14 alleles and 11 isoforms. B502 encoded 4 alleles that can generate 4 isoforms. Only 3 of these have been surveyed by serotyping. There are numerous null genes at this locus. DRB501 allele group 14 Alleles: 11 proteins, 2 Nulls * DR51 Serotype: 0101, 0102 * Serotype unknown: 0103 to 0107, 0109, 0110 to 0113 Nulls: 0108N, 0110N DRB502 allele group 4 Alleles: 4 proteins * DR51 Serotype: 0202, Serotype unknown: 0203 to 0205 Associated diseases DR51 serotype is positively associated with The following HLA-DRB ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	HLA-DR53 HLA-DR53 is an HLA-DR serotype that recognizes gene products of HLA-DRB4 locus. There are 13 alleles at this locus that encode 7 proteins. DRB3, DRB4, and DRB5 are minor DR beta encoding loci, they have been recognized as having distinct evolution. and the DRB4 locus presence is linked to HLA-DR7 seropositivity. The DRB4locus was apparently duplicated from an ancestor of the DRB1-DRB4 common locus around 5 million years ago. DRB4 locus is only apparent in a small subset of DQ haplotypes, and most individuals lack DRB4. In addition the level of normal expression is 8 fold lower than the DRB1 in cells which can express both. and lowered because of both transcriptional and post-transcriptional regulation. Alleles DR53 reactive alleles: DRB40101, 0103 Unknown reactivity: 0102, 0104 to 0107 Null alleles: 0101102N, 01030102N, 0201N, 0301N Associated diseases DRB401 is positively associated with Erythema multiforme, Crohn's disease, myasthenia gravis, rheumatoid arthriti ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]
	HLA-DR52 HLA-DR52 is an HLA-DR serotype that recognizes gene products of HLA-DRB3 locus. Three allele groups can produce 35 isoforms. DRB3, DRB4, and DRB5 are minor DR beta-encoding loci, and they have been recognized as having distinct evolution, having diverged from DRB1 around 4 million years ago. The DRB3 locus is only apparent in a small subset of DR haplotypes, and most individuals lack DRB3. Alleles Associated diseases DR52 serotype is positively associated with systemic sclerosis, inflammatory myopathies, inclusion body myositis, DRB301 is positively associated with sarcoidosis, Grave's Disease, pulmonary sarcoidosis, DRB30101:DRB10301 is linked to Lofgren's syndrome DRB30202 is also linked to Grave's disease, serum IgG antibodies to ''Chlamydia pneumoniae'' with essential hypertension, acute necrotizing encephalopathy DRB30301 is weakly associated with anticardiolipin antibodies in SLE DRB30301:DRB11302 may be associated with Crohn's disease DRB1 linkage HLA-DRB3 ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]
	HLA-DR17 HLA-DR17 (DR17) is an HLA- DR serotype that recognizes the DRB10301 and 0304 gene products. DR17 is found at high frequency in Western Europe (such as Western Ireland, N. Spain, Sardinia). DR17 is part of the broader antigen group HLA-DR3 and is very similar to the group HLA-DR18. Serology DR17 recognizes the DRB10301, 0304 alleles. Disease associations By serotype DR17 is associated with non-chronic sarcoidosis, infantile spasm/epilepsy, rabies vaccine-induced autoimmune encephalomyelitis and cardiovascular hypertrophy in subjects with arterial hypertension People with DR17 show a tendency toward benzylpenicilloyl allergies. By allele DRB10301: diabetes mellitus type 1, myositis, early onset Graves disease, type 1 autoimmune hepatitis, inflammatory inclusion body myositis. In autoimmune hepatitis, DRB10301 correlates with more severe and difficult to treat disease. By haplotype DRB10301:DQA105:DQB10201 is associated with diabetes mellitus type 1, ovarian cancer, ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]
	HLA-DR1 HLA-DR1 (DR1) is a HLA- DR serotype that recognizes the DRB101 gene products. It has been observed to be common among centenarians. Serology The serology for the most common DR1 alleles is excellent. The serology for alleles , , , , , , and is unknown. Disease associations By serotype DR1 is associated with seronegative-rheumatoid arthritis, penicillamine-induced myasthenia, and schizophrenia. DR1 is increased in patients with systemic sclerosis and arthritis and in ulcerative colitis with patients that have articular manifestations. By allele DRB10101 is associated with rheumatoid arthritis, in anti-Jk(a) mediated hemolytic transfusion reactions, foliaceous pemphigus, HTLV-1-associated myelopathy/tropical spastic paraparesis, and lichen planus. In lyme disease arthritis, 0101 appears to play a role in presentation of triggering microbial antigens. DRB10102 is associated with rheumatoid arthritis, in anti-Jk(a) mediated hemolytic transfusion reactions, psoriasis vu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Locus Locus (plural loci) is Latin for "place". It may refer to: Entertainment * Locus (comics), a Marvel Comics mutant villainess, a member of the Mutant Liberation Front * ''Locus'' (magazine), science fiction and fantasy magazine ** ''Locus Award'', presented to the winners of ''Locus'' magazine's annual readers' poll * ''Locus'' (video game), a 1995 video game by Zombie Studios * ''Locus'', a 2020 album by Satyr Computers and mathematics * Locus (mathematics), the set of points satisfying a particular condition, often forming a curve * LOCUS (operating system), a distributed OS developed at UCLA, notable for single-system image idea * Locus Computing Corporation (1982–1995), commercialized the LOCUS distributed operating system developed at UCLA * Locus Map, an Android navigation app using maps of various providers in online and offline mode * Locus Technologies (1997), an environmental software company that organizes data via the Internet * Root locus, a diagram visualizing th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]