killer T cell
Quick Summary
Killer T cells, also known as cytotoxic T cells, are a type of white blood cell crucial to the immune system. They are a type of lymphocyte, which are specialized white blood cells that identify specific foreign substances, or antigens, in the body.1
Cytology is the branch of biology that studies cells, including their structure, function, and pathology. Killer T cells are a key component of cell-mediated immunity. They work by directly destroying cells that display foreign or abnormal antigens on their surface, such as those infected by viruses or cancerous cells. These cells originate in the bone marrow and mature in the thymus before circulating in the blood and lymphatic system.213
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T cellcytotoxic T cells or become memory T cells. They are then sent to peripheral tissues or circulate in the blood or lymphatic system. Once stimulated by the appropriate antigen, helper T cells secrete chemical messengers called cytokines, which stimulate the differentiation of B cells into…
Read Morecytotoxic T cells or become memory T cells. They are then sent to peripheral tissues or circulate in the blood or lymphatic system. Once stimulated by the appropriate antigen, helper T cells secrete chemical messengers called cytokines, which stimulate the differentiation of B cells into…
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immune systemFunction of the T-cell receptor…types of mature T cells—cytotoxic T cells and helper T cells—are known. Some scientists hypothesize the existence of a third type of mature T cell called regulatory T cells. Some T cells recognize class I MHC molecules on the surface of cells; others bind to class II molecules. Cytotoxic…
Read More…types of mature T cells—cytotoxic T cells and helper T cells—are known. Some scientists hypothesize the existence of a third type of mature T cell called regulatory T cells. Some T cells recognize class I MHC molecules on the surface of cells; others bind to class II molecules. Cytotoxic…
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virusDiseaseIn cellular immunity, a killer T cell recognizes and kills a virus-infected cell because of the viral antigen on its surface, thus aborting the infection because a virus will not grow within a dead cell. If the virus-infected cells are not essential for host functions, the killer T cell…
Read MoreIn cellular immunity, a killer T cell recognizes and kills a virus-infected cell because of the viral antigen on its surface, thus aborting the infection because a virus will not grow within a dead cell. If the virus-infected cells are not essential for host functions, the killer T cell…
Read More- immune systemCell-mediated immune mechanisms
…mechanism of cell-mediated immunity involves cytotoxic T cells. They attach themselves by their receptors to target cells whose surface expresses appropriate antigens (notably ones made by developing viruses) and damage the infected cells enough to kill them.
Read More…mechanism of cell-mediated immunity involves cytotoxic T cells. They attach themselves by their receptors to target cells whose surface expresses appropriate antigens (notably ones made by developing viruses) and damage the infected cells enough to kill them.
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- immune systemActivation of killer cells
…cells, which may be either cytotoxic T cells or natural killer cells, have receptors that bind to the tail portion of the IgG antibody molecule (the part that does not bind to antigen). Once bound, killer cells insert a protein called perforin into the target cell, causing it to swell…
Read More…cells, which may be either cytotoxic T cells or natural killer cells, have receptors that bind to the tail portion of the IgG antibody molecule (the part that does not bind to antigen). Once bound, killer cells insert a protein called perforin into the target cell, causing it to swell…
Read More - immune systemResults of helper-T-cell activation
…which is that IL-2 allows cytotoxic or regulatory T cells that recognize the same antigen to become activated and to multiply. Cytotoxic T cells, in turn, can attack and kill other cells that express the foreign antigen in association with class I MHC molecules, which—as explained above—are present on almost…
Read More…which is that IL-2 allows cytotoxic or regulatory T cells that recognize the same antigen to become activated and to multiply. Cytotoxic T cells, in turn, can attack and kill other cells that express the foreign antigen in association with class I MHC molecules, which—as explained above—are present on almost…
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lymph node…activated helper T cells or cytotoxic T lymphocytes. All activated lymphocytes migrate through the medulla and enter the lymphatic circulation through the efferent lymphatic vessel, which drains either into adjacent lymph nodes or ultimately into the thoracic duct, a major vessel of the lymphatic system.
Read More…activated helper T cells or cytotoxic T lymphocytes. All activated lymphocytes migrate through the medulla and enter the lymphatic circulation through the efferent lymphatic vessel, which drains either into adjacent lymph nodes or ultimately into the thoracic duct, a major vessel of the lymphatic system.
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