All t cells originate from c-kit sca1 haematopoietic stem cells(hsc) which reside in the bone marrow. In some cases, the origin might be the fetal liver during embryonic development. The hsc then differentiate into multipotent progenitors (mpp) which retain the potential to become both myeloid and lymphoid cells. The process of differentiation then proceeds to a common lymphoid progenitor (clp), which can only differentiate into t, b or nk cells. t cell a type of white blood cell that is of key importance to the immune system and is at the core of adaptive immunity, the system that tailors the bodys immune response to specific pathogens. The t cells are like soldiers who search out and destroy the targeted invaders. Immature t cells (termed t-stem cells) migrate to the thymus gland in the neck, where they mature and differentiate. Immune system t cells t cells originate in the bone marrow and mature in the thymus. In the thymus, t cells multiply and differentiate into helper, regulatory, or cytotoxic t cells or become memory t cells. They are then sent to peripheral tissues or circulate in the blood or lymphatic system. T cells (also called t lymphocytes) are one of the main components of the adaptive immune system. They are vital in hosting an immune response against pathogens. T cells play a major role in defence against intracellular pathogens such as viruses, protozoa and intracellular bacteria, and in immunity to extracellular pathogens by providing help for the antibody response. t cells develop from hematopoietic stem cells in the bone marrow. Progenitors of those cells migrate to the thymus, here they are known as thymocytes. Thymocytes mature in a series of steps based on development of cell surface markers. Most cells in the thymus develop into t cells, while about 5 become t cells. The thymus is a specialized primary lymphoid organ of the immune system. T cells are critical to the adaptive immune system, where the body adapts specifically to foreign invaders. The thymus is located in the upper front part of the chest, in the anterior superior mediastinum, behind the sternum, and in front of the heart. It is made up of two lobes, each consisting of a central medulla and an outer cortex, surrounded by a capsule. Pre t cell receptor armed cells proliferate, creating a bunch of cells (clones) with identical beta chain and thus identical pre t-cell receptors 3. Formation of the pre t-cell signals cells to make the thymocyte double positive remember the cd4 is expressed first, followed by cd8 4. Essentially cell to cell combat with the good guys (t lymphocytes) killing the bad guys (any bad cells, such as bacteria, virus-infected cells, and cancer cells.). T cells are predominantly produced in the thymus some t cells however mature in the tonsils, hence the name t cells. T cells originate from hematopoietic stem cells, which after several stages of development result in a common lymphoid precursor.
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