blood_and_immune_upper_slim has part lacks_plasma_membrane_part has plasma membrane part develops from capable of has high plasma membrane amount mast cell Mast cells, also known as mastocytes, are a type of innate immune cell. They originate from multipotent hematopoietic progenitor cells within the bone marrow, after which they migrate into nearly all tissues throughout the body. In these tissues, mast cells undergo complete maturation, with the exception of the blood. They are most densely located in the interfaces between the internal and external environments, such as the skin, respiratory system, and gastrointestinal mucosa. Mast cells are crucial players against pathogens and serve as first-line defense components. They contain numerous granules rich in histamine and heparin and are known primarily for their role in allergy and anaphylaxis. Upon encountering an allergen, pathogen, or even certain drugs and toxins, mast cells release these mediators via degranulation. Histamine induces vasodilation and vascular permeability, allowing for immune cells to rapidly reach the site of infection, while heparin prevents clotting in these areas to facilitate immune cell recruitment. Mast cells may also selectively secrete mediators without degranulation. These cells also play other functions beyond immune defense. They are involved in wound healing processes and maintenance of tissue integrity, angiogenesis, and even regulation of physiological functions in the gut. Consequently, because of their wide-ranging impacts, abnormalities in mast cell function can result in various disorders, including those related to allergies, inflammation, and autoimmune conditions. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) FMA:66784 https://cellxgene.cziscience.com/cellguide/CL_0000097 A cell that is found in almost all tissues containing numerous basophilic granules and capable of releasing large amounts of histamine and heparin upon activation. Progenitors leave bone marrow and mature in connective and mucosal tissue. Mature mast cells are found in all tissues, except the bloodstream. Their phenotype is CD117-high, CD123-negative, CD193-positive, CD200R3-positive, and FceRI-high. Stem-cell factor (KIT-ligand; SCF) is the main controlling signal of their survival and development. BTO:0000830 histaminocyte labrocyte mastocyte CALOHA:TS-0603 tissue basophil Mast cells are generally integrin beta-7-negative and positive for TLR2, TLR3, TLR4, TLR5, TLR7, TLR9, C3aR, C5aR, CR3, CR4, VEGF, FGF2, and renin. They can express MHC Class I and II on their surface. Activated murine mast cells (IgE+Antigen) were capable of expressing the following co-stimulatory molecules: CD95 (Fas), CD120b, CD137 (4-1BB), CD153 (CD30L), CD154 (CD40L), GITR, ICOSL, OX40L, PD-L1, and PD-L2. Note that there was some mouse strain variation. Mast cells have also been demonstrated to produce bFGF, CCL2, CCL4, CCL5, CCL11, CCL20, CXCL2, CXCL8, CXCL10, GM-CSF, IFN-gamma, IL-1, IL-2, IL-3, IL-8, IL-10, IL-11, IL-12, IL-13, IL-16, IL-25, IL-18, MIP-1, prostaglandin D2, SCF, TGF-beta, TNF-alpha, TSLP, VEGF, and XCL1. They express the transcription factors Transcription factors AP-1, GATA1, MITF, Notch2, PIAS3, PU.1, and STAT5. myeloid leukocyte mast cell progenitor histamine secreting cell histamine production involved in inflammatory response prostaglandin production involved in inflammatory response positive regulation of peripheral tolerance induction positive regulation of leukocyte chemotaxis positive regulation of type 2 immune response secretory granule heparin proteoglycan biosynthetic process Homo sapiens C-C chemokine receptor type 3 interleukin-3 receptor class 2 alpha chain mast/stem cell growth factor receptor cell surface glycoprotein CD200 receptor 3 high affinity immunoglobulin epsilon receptor subunit alpha