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Immunogenic Cell Death
Immunogenic cell death is any type of cell death eliciting an immune response. Both accidental cell death and regulated cell death can result in immune response. Immunogenic cell death contrasts to forms of cell death ( apoptosis, autophagy or others) that do not elicit any response or even mediate immune tolerance. The name 'immunogenic cell death' is also used for one specific type of regulated cell death that initiates an immune response after stress to endoplasmic reticulum. Types of immunogenic cell death Immunogenic cell death types are divided according to molecular mechanisms leading up to, during and following the death event. The immunogenicity of a specific cell death is determined by antigens and adjuvant released during the process. Accidental cell death Accidental cell death is the result of physical, chemical or mechanical damage to a cell, which exceeds its repair capacity. It is an uncontrollable process, leading to loss of membrane integrity. The result is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Death
Cell death is the event of a biological cell ceasing to carry out its functions. This may be the result of the natural process of old cells dying and being replaced by new ones, as in programmed cell death, or may result from factors such as diseases, localized injury, or the death of the organism of which the cells are part. Apoptosis or Type I cell-death, and autophagy or Type II cell-death are both forms of programmed cell death, while necrosis is a non-physiological process that occurs as a result of infection or injury. Programmed cell death Programmed cell death (PCD) is cell death mediated by an intracellular program. PCD is carried out in a regulated process, which usually confers advantage during an organism's life-cycle. For example, the differentiation of fingers and toes in a developing human embryo occurs because cells between the fingers apoptose; the result is that the digits separate. PCD serves fundamental functions during both plant and metazoa (multicel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photodynamic Therapy
Photodynamic therapy (PDT) is a form of phototherapy involving light and a photosensitizing chemical substance, used in conjunction with molecular oxygen to elicit cell death (phototoxicity). PDT is popularly used in treating acne. It is used clinically to treat a wide range of medical conditions, including wet age-related macular degeneration, psoriasis, atherosclerosis and has shown some efficacy in anti-viral treatments, including herpes. It also treats malignant cancers including head and neck, lung, bladder and particular skin. The technology has also been tested for treatment of prostate cancer, both in a dog model and in human prostate cancer patients. It is recognised as a treatment strategy that is both minimally invasive and minimally toxic. Other light-based and laser therapies such as laser wound healing and rejuvenation, or intense pulsed light hair removal do not require a photosensitizer. Photosensitisers have been employed to sterilise blood plasma and wate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD40
Cluster of differentiation 40, CD40 is a costimulatory protein found on antigen-presenting cells and is required for their activation. The binding of CD154 ( CD40L) on TH cells to CD40 activates antigen presenting cells and induces a variety of downstream effects. Deficiency can cause Hyper-IgM syndrome type 3. Function The protein receptor encoded by this gene is a member of the TNF-receptor superfamily. This receptor has been found to be essential in mediating a broad variety of immune and inflammatory responses including T cell-dependent immunoglobulin class switching, memory B cell development, and germinal center formation. AT-hook transcription factor AKNA is reported to coordinately regulate the expression of this receptor and its ligand, which may be important for homotypic cell interactions. The interaction of this receptor and its ligand is found to be necessary for amyloid-beta-induced microglial activation, and thus is thought to be an early event in Alzheimer d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD91
Low density lipoprotein receptor-related protein 1 (LRP1), also known as alpha-2-macroglobulin receptor (A2MR), apolipoprotein E receptor (APOER) or cluster of differentiation 91 (CD91), is a protein forming a receptor found in the plasma membrane of cells involved in receptor-mediated endocytosis. In humans, the LRP1 protein is encoded by the ''LRP1'' gene. LRP1 is also a key signalling protein and, thus, involved in various biological processes, such as lipoprotein metabolism and cell motility, and diseases, such as neurodegenerative diseases, atherosclerosis, and cancer. Structure The ''LRP1'' gene encodes a 600 kDa precursor protein that is processed by furin in the trans- Golgi complex, resulting in a 515 kDa alpha-chain and an 85 kDa beta-chain associated noncovalently. As a member of the LDLR family, LRP1 contains cysteine-rich complement-type repeats, EGF (gene) repeats, β-propeller domains, a transmembrane domain, and a cytoplasmic domain. The extracellular domain o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HSP90
Hsp90 (heat shock protein 90) is a chaperone protein that assists other proteins to fold properly, stabilizes proteins against heat stress, and aids in protein degradation. It also stabilizes a number of proteins required for tumor growth, which is why Hsp90 inhibitors are investigated as anti-cancer drugs. Heat shock proteins, as a class, are among the most highly expressed cellular proteins across all species. As their name implies, heat shock proteins protect cells when stressed by elevated temperatures. They account for 1–2% of total protein in unstressed cells. However, when cells are heated, the fraction of heat shock proteins increases to 4–6% of cellular proteins. Heat shock protein 90 (Hsp90) is one of the most common of the heat-related proteins. The "90" comes from the fact that it has a mass of roughly 90 kilodaltons. A 90 kDa protein is considered fairly large for a non-fibrous protein. Hsp90 is found in bacteria and all branches of eukarya, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HSP70
The 70 kilodalton heat shock proteins (Hsp70s or DnaK) are a family of conserved ubiquitously expressed heat shock proteins. Proteins with similar structure exist in virtually all living organisms. Intracellularly localized Hsp70s are an important part of the cell's machinery for protein folding, performing chaperoning functions, and helping to protect cells from the adverse effects of physiological stresses. Additionally, membrane-bound Hsp70s have been identified as a potential target for cancer therapies and their extracellularly localized counterparts have been identified as having both membrane-bound and membrane-free structures. Discovery Members of the Hsp70 family are very strongly upregulated by heat stress and toxic chemicals, particularly heavy metals such as arsenic, cadmium, copper, mercury, etc. Heat shock was originally discovered by Ferruccio Ritossa in the 1960s when a lab worker accidentally boosted the incubation temperature of Drosophila (fruit flies). Wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat-shock Proteins
Heat shock proteins (HSP) are a family of proteins produced by cells in response to exposure to stressful conditions. They were first described in relation to heat shock, but are now known to also be expressed during other stresses including exposure to cold, UV light and during wound healing or tissue remodeling. Many members of this group perform chaperone functions by stabilizing new proteins to ensure correct folding or by helping to refold proteins that were damaged by the cell stress. This increase in expression is transcriptionally regulated. The dramatic upregulation of the heat shock proteins is a key part of the heat shock response and is induced primarily by heat shock factor (HSF). HSPs are found in virtually all living organisms, from bacteria to humans. Heat-shock proteins are named according to their molecular weight. For example, Hsp60, Hsp70 and Hsp90 (the most widely studied HSPs) refer to families of heat shock proteins on the order of 60, 70 and 90 kilodal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phagocytes
Phagocytes are cells that protect the body by ingesting harmful foreign particles, bacteria, and dead or dying cells. Their name comes from the Greek ', "to eat" or "devour", and "-cyte", the suffix in biology denoting "cell", from the Greek ''kutos'', "hollow vessel". They are essential for fighting infections and for subsequent immunity. Phagocytes are important throughout the animal kingdom and are highly developed within vertebrates. One litre of human blood contains about six billion phagocytes. They were discovered in 1882 by Ilya Ilyich Mechnikov while he was studying starfish larvae.Ilya Mechnikov retrieved on November 28, 2008. Fro ''Physiology or Medicine 1901–1921'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calreticulin
Calreticulin also known as calregulin, CRP55, CaBP3, calsequestrin-like protein, and endoplasmic reticulum resident protein 60 (ERp60) is a protein that in humans is encoded by the ''CALR'' gene. Calreticulin is a multifunctional soluble protein that binds Ca2+ ions (a second messenger in signal transduction), rendering it inactive. The Ca2+ is bound with low affinity, but high capacity, and can be released on a signal (see inositol trisphosphate). Calreticulin is located in storage compartments associated with the endoplasmic reticulum and is considered an ER resident protein. The term "Mobilferrin" is considered to be the same as calreticulin by some sources. Function Calreticulin binds to misfolded proteins and prevents them from being exported from the endoplasmic reticulum to the Golgi apparatus. A similar quality-control molecular chaperone, calnexin, performs the same service for soluble proteins as does calreticulin, however it is a membrane-bound protein. Bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DAMPs
Damage-associated molecular patterns (DAMPs) are molecules within cells that are a component of the innate immune response released from damaged or dying cells due to trauma or an infection by a pathogen. They are also known as danger-associated molecular patterns, danger signals, and alarmin because they serve as a warning sign for the organism to alert it of any damage or infection to its cells. DAMPs are endogenous danger signals that are discharged to the extracellular space in response to damage to the cell from trauma or pathogen. Once a DAMP is released from the cell, it promotes a noninfectious inflammatory response by binding to a pattern-recognition receptor. Inflammation is a key aspect of the innate immune response because it is used to help mitigate future damage to the organism by removing harmful invaders from the affected area and start the healing process. As an example, the cytokine IL-1α is a DAMP that originates within the nucleus of the cell, which once rel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T Cell
A T cell is a type of lymphocyte. T cells are one of the important white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor (TCR) on their cell surface. T cells are born from hematopoietic stem cells, found in the bone marrow. Developing T cells then migrate to the thymus gland to develop (or mature). T cells derive their name from the thymus. After migration to the thymus, the precursor cells mature into several distinct types of T cells. T cell differentiation also continues after they have left the thymus. Groups of specific, differentiated T cell subtypes have a variety of important functions in controlling and shaping the immune response. One of these functions is immune-mediated cell death, and it is carried out by two major subtypes: CD8+ "killer" and CD4+ "helper" T cells. (These are named for the presence of the cell surface proteins CD8 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
