This article needs to be updated.(February 2018) |
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Organisms | immune cells in the mouse. |
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Laboratory | various labs in US |
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Website | www |
The Immunological Genome Project (ImmGen) is a collaborative scientific research project that is currently building a gene-expression database for all characterized immune cells in the mouse. The overarching goal of the project is to computationally reconstruct the gene regulatory network in immune cells
. [1] All data generated as part of ImmGen are made freely and publicly available at the ImmGen portal .
The ImmGen project began in 2008, as a collaboration between several immunology and computational biology laboratories across the United States, and will be completing its second phase on 2017. Currently, raw data and specialized data browsers from the first and second phases are on www.ImmGen.org.
A true understanding of cell differentiation in the immune system will require a general perspective on the transcriptional profile of each cell type of the adaptive and innate immune systems, and how these profiles evolve through cell differentiation or activation by immunogenic or tolerogenic ligands. The ImmGen project aims to establish the roadmap of these transcriptional states.[ citation needed ]
The first aim of ImmGen is to generate a compendium of whole-genome transcriptional profiles (initially by microarray, now mostly by RNA-sequencing) for nearly all characterized cell populations of the adaptive and innate immune systems in the mouse, at major stages of differentiation and activation. This effort is being carried out by a group of collaborating immunology research laboratories across the U.S. Each of the laboratories brings a unique expertise in a particular cell lineage, and all are employing standardized procedures for cell sorting. The compendium of microarray data currently include over 250 immunologically relevant cell types, from all lymphoid organs and other tissues which are monitored by immune cells.[ citation needed ]
A series of ImmGen reports was published as the compendium accumulated. Some lineage specific reports described hematopoietic stem cells, [2] natural killer cells, [3] neutrophiles, [4] B and T cells, [5] natural killer cells, [6] macrophage, [7] dendritic cells, [8] alpha beta T cells, [9] gamma delta T cells, [10] activated CD8 T cells, [11] innate lymphoid cells, [12] and lymph node stromal cells. [13] Though most of the transcriptional profiling was done on B6 mice, the effect of genetic variation was also studied. [14] The second phase of ImmGen started profiling activated immune cells. The interferon response was used as a test case. [15]
Several groups of collaborating computational biologists (Regev & Koller) used the data to reverse-engineer the genetic regulatory network in immune cells, [16] and compare it to the human immune system [17] An initial survey of differential splicing across immune lineages was carried out using both microarrays and RNA-sequencing. [18]
Project participants from Brown University's Computer Sciences Department are also exploring novel representation modes for the ImmGen data, developing and curating the public representation.[ citation needed ]
Participating Immunology laboratories include the Brenner (NKT, BWH, Boston), Goldrath (Activated CD8 T cells, UCSD, San Diego), Kang (gamma delta T cells, U. Mass, Worcester), Lanier (NK, UCSF, San Francisco), Mathis/Benoist (alpha beta T cells, HMS, Boston), Merad and Randolph (monocytes & macrophages, Mount Sinai, New York and Washington University, Saint Louis), Rossi (HSC, Children's, Boston), Turley (DC, DFCI, Boston), and Wagers (HSC, Joslin, Boston) labs.[ citation needed ]
Tragically, Richard (Randy) Hardy (Fox Chase, Philadelphia), who was an ImmGen member since its initiation, passed away in June 2016.
As of August 2016, Immgen has profiled more than 250 naive cell populations in the mouse using microarrays, and several dozens of activated cell types using RNA-sequencing.[ citation needed ]
The project's status and detailed information can be seen at (ImmGen). This site also includes a dedicated data browser, with which users can interactively explore the expression profiles for particular genes, networks of co-regulated genes, and genes that best distinguish different cell types. Raw data are available at the NCBI's Gene Expression Omnibus
FOXP3, also known as scurfin, is a protein involved in immune system responses. A member of the FOX protein family, FOXP3 appears to function as a master regulator of the regulatory pathway in the development and function of regulatory T cells. Regulatory T cells generally turn the immune response down. In cancer, an excess of regulatory T cell activity can prevent the immune system from destroying cancer cells. In autoimmune disease, a deficiency of regulatory T cell activity can allow other autoimmune cells to attack the body's own tissues.
In the human immune system, central tolerance is the process of eliminating any developing T or B lymphocytes that are reactive to self. Through elimination of autoreactive lymphocytes, tolerance ensures that the immune system does not attack self peptides. Lymphocyte maturation occurs in primary lymphoid organs such as the bone marrow and the thymus. In mammals, B cells mature in the bone marrow and T cells mature in the thymus.
In academia, computational immunology is a field of science that encompasses high-throughput genomic and bioinformatics approaches to immunology. The field's main aim is to convert immunological data into computational problems, solve these problems using mathematical and computational approaches and then convert these results into immunologically meaningful interpretations.
Immune tolerance, or immunological tolerance, or immunotolerance, is a state of unresponsiveness of the immune system to substances or tissue that would otherwise have the capacity to elicit an immune response in a given organism. It is induced by prior exposure to that specific antigen and contrasts with conventional immune-mediated elimination of foreign antigens. Tolerance is classified into central tolerance or peripheral tolerance depending on where the state is originally induced—in the thymus and bone marrow (central) or in other tissues and lymph nodes (peripheral). The mechanisms by which these forms of tolerance are established are distinct, but the resulting effect is similar.
Nuclear transcription factor Y subunit alpha is a protein that in humans is encoded by the NFYA gene.
C-C chemokine receptor type 10 is a protein that in humans is encoded by the CCR10 gene.
Chemokine-binding protein 2 is a protein that in humans is encoded by the CCBP2 gene.
Interleukin 10 receptor, beta subunit is a subunit for the interleukin-10 receptor. IL10RB is its human gene.
Microtubule-associated serine/threonine-protein kinase 2 is an enzyme that in humans is encoded by the MAST2 gene. The protein encoded by this gene controls TRAF6 and NF-kappaB activity.
Progesterone-induced-blocking factor 1 is a protein that in humans is encoded by the PIBF1 gene. It has been shown to localize to the centrosome and has also been named CEP90.
Sialic acid-binding Ig-like lectin 10 is a protein that in humans is encoded by the SIGLEC10 gene. Siglec-G is often referred to as the murine paralog of human Siglec-10
Krueppel-like factor 17 is a protein that in humans is encoded by the KLF17 gene.
The NSG mouse is a brand of immunodeficient laboratory mice, developed and marketed by Jackson Laboratory, which carries the strain NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ. NSG branded mice are among the most immunodeficient described to date. NSG branded mice lack mature T cells, B cells, and natural killer (NK) cells. NSG branded mice are also deficient in multiple cytokine signaling pathways, and they have many defects in innate immunity. The compound immunodeficiencies in NSG branded mice permit the engraftment of a wide range of primary human cells, and enable sophisticated modeling of many areas of human biology and disease. NSG branded mice were developed in the laboratory of Dr. Leonard Shultz at Jackson Laboratory, which owns the NSG trade mark.
Somatic hypermutation is a cellular mechanism by which the immune system adapts to the new foreign elements that confront it, as seen during class switching. A major component of the process of affinity maturation, SHM diversifies B cell receptors used to recognize foreign elements (antigens) and allows the immune system to adapt its response to new threats during the lifetime of an organism. Somatic hypermutation involves a programmed process of mutation affecting the variable regions of immunoglobulin genes. Unlike germline mutation, SHM affects only an organism's individual immune cells, and the mutations are not transmitted to the organism's offspring. Mistargeted somatic hypermutation is a likely mechanism in the development of B-cell lymphomas and many other cancers.
Immunomics is the study of immune system regulation and response to pathogens using genome-wide approaches. With the rise of genomic and proteomic technologies, scientists have been able to visualize biological networks and infer interrelationships between genes and/or proteins; recently, these technologies have been used to help better understand how the immune system functions and how it is regulated. Two thirds of the genome is active in one or more immune cell types and less than 1% of genes are uniquely expressed in a given type of cell. Therefore, it is critical that the expression patterns of these immune cell types be deciphered in the context of a network, and not as an individual, so that their roles be correctly characterized and related to one another. Defects of the immune system such as autoimmune diseases, immunodeficiency, and malignancies can benefit from genomic insights on pathological processes. For example, analyzing the systematic variation of gene expression can relate these patterns with specific diseases and gene networks important for immune functions.
CD94/NKG2 is a family of C-type lectin receptors which are expressed predominantly on the surface of NK cells and a subset of CD8+ T-lymphocyte. These receptors stimulate or inhibit cytotoxic activity of NK cells, therefore they are divided into activating and inhibitory receptors according to their function. CD94/NKG2 recognize nonclassical MHC glycoproteins class I (HLA-E in human and Qa-1 molecules in the mouse).
The immunome is the set of genes and proteins that constitute the immune system, excluding those that are widespread in other cell types, and not involved in the immune response itself. It is further defined as the set of peptides derived from the proteome that interact with the immune system. There are numerous ongoing efforts to characterize and sequence the immunomes of humans, mice, and elements of non-human primates. Typically, immunomes are studied using immunofluorescence microscopy to determine the presence and activity of immune-related enzymes and pathways. Practical applications for studying the immunome include vaccines, therapeutic proteins, and further treatment of other diseases. The study of the immunome falls under the field of immunomics.
Medullary thymic epithelial cells (mTECs) represent a unique stromal cell population of the thymus which plays an essential role in the establishment of central tolerance. Therefore, mTECs rank among cells relevant for the development of functional mammal immune system.
Promiscuous gene expression (PGE), formerly referred to as ectopic expression, is a process specific to the thymus that plays a pivotal role in the establishment of central tolerance. This phenomenon enables generation of self-antigens, so called tissue-restricted antigens (TRAs), which are in the body expressed only by one or few specific tissues. These antigens are represented for example by insulin from the pancreas or defensins from the gastrointestinal tract. Antigen-presenting cells (APCs) of the thymus, namely medullary thymic epithelial cells (mTECs), dendritic cells (DCs) and B cells are capable to present peptides derived from TRAs to developing T cells and hereby test, whether their T cell receptors (TCRs) engage self entities and therefore their occurrence in the body can potentially lead to the development of autoimmune disease. In that case, thymic APCs either induce apoptosis in these autoreactive T cells or they deviate them to become T regulatory cells, which suppress self-reactive T cells in the body that escaped negative selection in the thymus. Thus, PGE is crucial for tissues protection against autoimmunity.
Gwendalyn J. Randolph is an American immunologist, the Emil R. Unanue Distinguished Professor in the Department of Immunology and Pathology at Washington University in St. Louis, Missouri, where she is currently co-director of the Immunology Graduate Program. During her postdoctoral work, Randolph characterized monocyte differentiation to dendritic cells and macrophages and made advances in our understanding of dendritic cell trafficking and the fate of monocytes recruited to sites of inflammation. Her lab has contributed to the Immunological Genome Project by characterizing macrophage gene expression. Her work now focuses on the immunological mechanisms driving atherosclerosis and inflammatory bowel disease (IBD) by exploring lymphatic function and lipoprotein trafficking.