cytotoxic
Physiology
(adjective)
Of or relating to cytotoxicity.
Microbiology
(adjective)
of, relating to, or being a cytotoxin
Examples of cytotoxic in the following topics:
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Natural Killer Cells
- Natural Killer (NK) cells are cytotoxic lymphocytes critical for the innate immune system.
- Natural killer cells (NK cells) are cytotoxic lymphocyte critical to the innate immune system.
- The role of NK cells is similar to that of cytotoxic T cells in the adaptive immune response.
- To control their cytotoxic activity, NK cells possess two types of surface receptors: activating receptors and inhibitory receptors.
- Schematic diagram indicating the complementary activities of cytotoxic T-cells and NK cells.
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Type II (Cytotoxic) Reactions
- In type II (cytotoxic) hypersensitivity, the antibodies produced by the immune response bind to antigens on the patient's own cell surfaces.
- In type II hypersensitivity (or cytotoxic hypersensitivity), the antibodies produced by the immune response bind to antigens on the patient's own cell surfaces.
- Another form of type II hypersensitivity is called antibody-dependent cell-mediated cytotoxicity (ADCC).
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Natural Killer Cells
- Natural killer cells (or NK cells) are a type of cytotoxic lymphocyte critical to the innate immune system.
- Natural killer cells (or NK cells) are a type of cytotoxic lymphocyte critical to the innate immune system.
- The role NK cells play is similar to that of cytotoxic T cells in the vertebrate adaptive immune response.
- Schematic diagram indicating the complementary activities of cytotoxic T-cells and NK cells.
- Schematic diagram indicating the complementary activities of cytotoxic T-cells and NK cells.
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Specific T-Cell Roles
- T helper cells assist the maturation of B cells and memory B cells while activating cytotoxic T cells and macrophages.
- Their primary functions include antigen presentation and activation of B cells, and activation of cytotoxic T cells and macrophages.
- Cytotoxic T cells recognize their antigen on pathogens through their T cell receptor, and will kill the pathogen through degranulation and cell-mediated apoptosis.
- The cytotoxic enzymes and proteases travel to their target cell through a microtubule cytoskeleton.
- Effector memory cells may be either CD4+ or CD8+, and will produce either helper or cytotoxic T cells in a secondary immune response.
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Types of Adaptive Immunity
- Cell mediated immunity is controlled by type 1 helper T-cells (Th1) and cytotoxic T-cells.
- Helper-T cells facilitate the immune response by guiding cytotoxic T-cells to pathogens or pathogen-infected cells, while the cytotoxic T-cells will kill the pathogens or pathogen-infected cells.
- Some of the ways in which cytotoxic T-cells kill pathogens include the release of granules that contain the cytotoxins perforin and granzyme, which lyse small pores in the membrane of a pathogen.
- Helper-T cells will secrete cytokines, such as interferon-gamma, which can activate cytotoxic T-cells and macrophages.
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Classes of T Cells
- Effector cells include helper T cells, and cytolytic or cytotoxic T cells.
- Cytolytic or cytotoxic T cells (characterized by the expression of CD8 marker on their surface) kill cells that produce foreign antigens, such as cells infected by viruses and other intracellular microbes .
- Distinguish between: naive, effector (helper and cytotoxic), memory and regulatory T cells
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Tests That Differentiate Between T Cells and B cells
- Methods used to differentiate T cells and B cells include staining cell surface receptors and functional assays like the T lymphocyte cytotoxicity assay.
- Another functional assay used to identify T-lymphocyte is the cytotoxic activity assay.
- Describe how T cells and B cells can be differentiated using staining of cell surface receptors and functional assays like the T lymphocyte cytotoxicity assay
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Antimicrobial Peptides
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Overview of Adaptive Immunity
- The antigen is presented to immature helper T cells and cytotoxic T cells through binding the MHC II (helper T) or MHC I (cytotoxic T) to T-cell receptors.
- Helper T cells activate B cells, which proliferate and produce antibodies specific to the antigen, while cytotoxic T cells destroy pathogens that bear the antigen that was presented to them by the APCs.
- Antigen presentation stimulates T cells to become either "cytotoxic" CD8+ cells or "helper" CD4+ cells.
- Cytotoxic cells directly attack other cells carrying certain foreign or abnormal molecules on their surfaces.
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Cell-Mediated Immunity
- Cell-mediated immunity involves cytotoxic T cells recognizing infected cells and bringing about their destruction.
- Cytotoxic T cells mediate one arm of the cellular immune response
- There are two main types of T cells: helper T lymphocytes (TH) and the cytotoxic T lymphocytes (TC).
- The TH lymphocytes function indirectly to tell other immune cells about potential pathogens, while cytotoxic T cells (TC) are the key component of the cell-mediated part of the adaptive immune system which attacks and destroys infected cells.