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Anti-PD-1
Programmed cell death protein 1, also known as PD-1 and CD279 ( cluster of differentiation 279), is a protein on the surface of T and B cells that has a role in regulating the immune system's response to the cells of the human body by down-regulating the immune system and promoting self-tolerance by suppressing T cell inflammatory activity. This prevents autoimmune diseases, but it can also prevent the immune system from killing cancer cells. PD-1 is an immune checkpoint and guards against autoimmunity through two mechanisms. First, it promotes apoptosis (programmed cell death) of antigen-specific T-cells in lymph nodes. Second, it reduces apoptosis in regulatory T cells (anti-inflammatory, suppressive T cells). PD-1 inhibitors, a new class of drugs that block PD-1, activate the immune system to attack tumors and are used to treat certain types of cancer. The PD-1 protein in humans is encoded by the ''PDCD1'' gene. PD-1 is a cell surface receptor that belongs to the im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PD-1 Inhibitor
Cancer immunotherapy (sometimes called immuno-oncology) is the stimulation of the immune system to treat cancer, improving on the immune system's natural ability to fight the disease. It is an application of the fundamental research of cancer immunology and a growing subspecialty of oncology. Cancer immunotherapy exploits the fact that cancer cells often have tumor antigens, molecules on their surface that can be detected by the antibody proteins of the immune system, binding to them. The tumor antigens are often proteins or other macromolecules (e.g., carbohydrates). Normal antibodies bind to external pathogens, but the modified immunotherapy antibodies bind to the tumor antigens marking and identifying the cancer cells for the immune system to inhibit or kill. Clinical success of cancer immunotherapy is highly variable between different forms of cancer; for instance, certain subtypes of gastric cancer react well to the approach whereas immunotherapy is not effective for other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immune Checkpoint
Immune checkpoints are regulators of the immune system. These pathways are crucial for self-tolerance, which prevents the immune system from attacking cells indiscriminately. However, some cancers can protect themselves from attack by stimulating immune checkpoint targets. Inhibitory checkpoint molecules are targets for cancer immunotherapy due to their potential for use in multiple types of cancers. Currently approved checkpoint inhibitors block CTLA4 and PD-1 and PD-L1. For the related basic science discoveries, James P. Allison and Tasuku Honjo won the Tang Prize in Biopharmaceutical Science and the Nobel Prize in Physiology or Medicine in 2018. Stimulatory checkpoint molecules Four stimulatory checkpoint molecules are members of the tumor necrosis factor (TNF) receptor superfamily—CD27, CD40, OX40, GITR and CD137. Another two stimulatory checkpoint molecules belong to the B7-CD28 superfamily—CD28 itself and ICOS. * CD27: This molecule supports antigen-specific ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cluster Of Differentiation
The cluster of differentiation (also known as cluster of designation or classification determinant and often abbreviated as CD) is a protocol used for the identification and investigation of cell surface molecules providing targets for immunophenotyping of cells. In terms of physiology, CD molecules can act in numerous ways, often acting as receptors or ligands important to the cell. A signal cascade is usually initiated, altering the behavior of the cell (see cell signaling). Some CD proteins do not play a role in cell signaling, but have other functions, such as cell adhesion. CD for humans is numbered up to 371 (). Nomenclature The CD nomenclature was proposed and established in the 1st International Workshop and Conference on Human Leukocyte Differentiation Antigens (HLDA), which was held in Paris in 1982. This system was intended for the classification of the many monoclonal antibodies (mAbs) generated by different laboratories around the world against epitopes on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD273
Programmed cell death 1 ligand 2 (also known as PD-L2, B7-DC) is a protein that in humans is encoded by the ''PDCD1LG2'' gene. PDCD1LG2 has also been designated as CD273 (cluster of differentiation 273). PDCD1LG2 is an immune checkpoint receptor ligand which plays a role in negative regulation of the adaptive immune response. PD-L2 is one of two known ligands for Programmed cell death protein 1 (PD-1). Structure PD-L2 is a cell surface receptor belonging to the B7 protein family. It consists of both an immunoglobulin-like variable domain and an immunoglobulin-like constant domain in the extracellular region, a transmembrane domain, and a cytoplasmic domain. PD-L2 shares considerable sequence homology with other B7 proteins, but it does not contain the putative binding sequence for CD28/CTLA4, namely SQDXXXELY or XXXYXXRT. The crystal structure of murine PD-L2 bound to murine PD-1 has been determined. as well as the structure of the hPD-L2/mutant hPD-1 complex. Expressi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PTPN6
Tyrosine-protein phosphatase non-receptor type 6, also known as Src homology region 2 domain-containing phosphatase-1 (SHP-1), is an enzyme that in humans is encoded by the ''PTPN6'' gene. Function The protein encoded by this gene is a member of the protein tyrosine phosphatase (PTP) family. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitotic cycle, and oncogenic transformation. N-terminal part of this PTP contains two tandem Src homolog ( SH2) domains, which act as protein phospho-tyrosine binding domains, and mediate the interaction of this PTP with its substrates. This PTP is expressed primarily in hematopoietic cells, and functions as an important regulator of multiple signaling pathways in hematopoietic cells. This PTP has been shown to interact with, and dephosphorylate a wide spectrum of phospho-proteins involved in hematopoietic cell signaling, (e.g., the LYN-CD22-SHP-1 pathway). Multiple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T-cell Receptor
The T-cell receptor (TCR) is a protein complex found on the surface of T cells, or T lymphocytes, that is responsible for recognizing fragments of antigen as peptides bound to major histocompatibility complex (MHC) molecules. The binding between TCR and antigen peptides is of relatively low affinity and is degenerate: that is, many TCRs recognize the same antigen peptide and many antigen peptides are recognized by the same TCR. The TCR is composed of two different protein chains (that is, it is a heterodimer). In humans, in 95% of T cells the TCR consists of an alpha (α) chain and a beta (β) chain (encoded by '' TRA'' and ''TRB'', respectively), whereas in 5% of T cells the TCR consists of gamma and delta (γ/δ) chains (encoded by '' TRG'' and '' TRD'', respectively). This ratio changes during ontogeny and in diseased states (such as leukemia). It also differs between species. Orthologues of the 4 loci have been mapped in various species. Each locus can produce a vari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoreceptor Tyrosine-based Inhibitory Motif
An immunoreceptor tyrosine-based inhibitory motif (ITIM), is a conserved sequence of amino acids that is found intracellularly in the cytoplasmic domains of many inhibitory receptors of the non-catalytic tyrosine-phosphorylated receptor family found on immune cells. These immune cells include T cells, B cells, NK cells, dendritic cells, macrophages and mast cells. ITIMs have similar structures of S/I/V/LxYxxI/V/L, where x is any amino acid, Y is a tyrosine residue that can be phosphorylated, S is the amino acide Serine, I is the amino acid Isoleucine, and V is the amino acid Valine. ITIMs recruit SH2 domain-containing phosphatases, which inhibit cellular activation. ITIM-containing receptors often serve to target Immunoreceptor tyrosine-based activation motif(ITAM)-containing receptors, resulting in an innate inhibition mechanism within cells. ITIM bearing receptors have important role in regulation of immune system allowing negative regulation at different levels of the immune res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorylation
In chemistry, phosphorylation is the attachment of a phosphate group to a molecule or an ion. This process and its inverse, dephosphorylation, are common in biology and could be driven by natural selection. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License. Protein phosphorylation often activates (or deactivates) many enzymes. Glucose Phosphorylation of sugars is often the first stage in their catabolism. Phosphorylation allows cells to accumulate sugars because the phosphate group prevents the molecules from diffusing back across their transporter. Phosphorylation of glucose is a key reaction in sugar metabolism. The chemical equation for the conversion of D-glucose to D-glucose-6-phosphate in the first step of glycolysis is given by :D-glucose + ATP → D-glucose-6-phosphate + ADP : ΔG° = −16.7 kJ/mol (° indicates measurement at standard condition) Hepatic cells are freely permeable to glucose, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmembrane
A transmembrane protein (TP) is a type of integral membrane protein that spans the entirety of the cell membrane. Many transmembrane proteins function as gateways to permit the transport of specific substances across the membrane. They frequently undergo significant conformational changes to move a substance through the membrane. They are usually highly hydrophobic and aggregate and precipitate in water. They require detergents or nonpolar solvents for extraction, although some of them (beta-barrels) can be also extracted using denaturing agents. The peptide sequence that spans the membrane, or the transmembrane segment, is largely hydrophobic and can be visualized using the hydropathy plot. Depending on the number of transmembrane segments, transmembrane proteins can be classified as single-span (or bitopic) or multi-span (polytopic). Some other integral membrane proteins are called monotopic, meaning that they are also permanently attached to the membrane, but do not pass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoglobulin Superfamily
The immunoglobulin superfamily (IgSF) is a large protein superfamily of cell surface and soluble proteins that are involved in the recognition, binding, or adhesion processes of cells. Molecules are categorized as members of this superfamily based on shared structural features with immunoglobulins (also known as antibodies); they all possess a domain known as an immunoglobulin domain or fold. Members of the IgSF include cell surface antigen receptors, co-receptors and co-stimulatory molecules of the immune system, molecules involved in antigen presentation to lymphocytes, cell adhesion molecules, certain cytokine receptors and intracellular muscle proteins. They are commonly associated with roles in the immune system. Otherwise, the sperm-specific protein IZUMO1, a member of the immunoglobulin superfamily, has also been identified as the only sperm membrane protein essential for sperm-egg fusion. Immunoglobulin domains Proteins of the IgSF possess a structural domain known as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CTLA-4
CTLA-4 or CTLA4 (cytotoxic T-lymphocyte-associated protein 4), also known as CD152 (cluster of differentiation 152), is a protein receptor that functions as an immune checkpoint and downregulates immune responses. CTLA-4 is constitutively expressed in regulatory T cells but only upregulated in conventional T cells after activation – a phenomenon which is particularly notable in cancers. It acts as an "off" switch when bound to CD80 or CD86 on the surface of antigen-presenting cells. The CTLA-4 protein is encoded by the ''Ctla-4'' gene in mice and the ''CTLA-4'' gene in humans. History CTLA-4 was first identified in 1991 as a second receptor for the T cell costimulation ligand B7. In November 1995, the labs of Tak Wah Mak and Arlene H. Sharpe independently published their findings on the discovery of the function of CTLA-4 as a negative regulator of T-cell activation, by knocking out the gene in mice. Previous studies from several labs had used methods which could not def ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD28
CD28 (Cluster of Differentiation 28) is one of the proteins expressed on T cells that provide co-stimulatory signals required for T cell activation and survival. T cell stimulation through CD28 in addition to the T-cell receptor ( TCR) can provide a potent signal for the production of various interleukins ( IL-6 in particular). CD28 is the receptor for CD80 (B7.1) and CD86 (B7.2) proteins. When activated by Toll-like receptor ligands, the CD80 expression is upregulated in antigen-presenting cells (APCs). The CD86 expression on antigen-presenting cells is constitutive (expression is independent of environmental factors). CD28 is the only B7 receptor constitutively expressed on naive T cells. Association of the TCR of a naive T cell with MHC:antigen complex without CD28:B7 interaction results in a T cell that is anergic. Furthermore, CD28 was also identified on bone marrow stromal cells, plasma cells, neutrophils and eosinophils, but the functional importance of CD28 on these ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
