台北医学大学-StructureandFunctionofHematologicSystem.pptVIP

Eosinophil (1) 1. peroxidase a) no role in bacteriocidal response b) lower bacteriocidal activity than neuts c) toxic even without peroxide d) potentiates effects of moncytes on bacteria 2. Catalase -- developmentally related to peroxisomes 3. lipid oxidases -- enoyl-Co A hydratase, Acyl CoA oxidase etc. 4. Lectins -- exist in crystalloids Eosinophil (2) 5. Basic proteins 6. Cationic protein (ECP) 7. Membrane protein reservoir 8. Lipid bodies 9. Other proteins Eosinophil (3) 1. Turnover time 4.5 days Tissue lifetime 2-4 days Blood lifetime 48 h 2. throughout body -- most prominent in GI 3. Eosinophilia typical in parasitic infection or allergic Rx, Hodgkins Dz, carcinoma 4. Eosinopenia -- acute stress or inflammation Eosinophil (4) 1. Tissue wound repair 2. Anti-neoplastic – cytotoxic to tumors 3. T cell-mediated Rx 4. Parasitic host defense 5. Reversible tissue injury 6. Irreversible tissue Injury hypereosinophila syndromes Basophils, Mast Cells (1) Relationship between mast cells and basophils is unclear Similar in structure, components, function but not identical Preformed granule content mediators: a) histamine -- blood vessel dilation -- lower blood pressure (shock) -- increased capillary permeability and blood leakage b) acid muco-polysacchararides (e.g. heparin) inhibits coagulation c) proteoglycans -- helps in the storage of histamine d) cationic proteases e) glycosidases Stimulation and generation of arachidonic acid Cytokine release Basophils, Mast Cells (2) a) IgE recognize specific allergens b) allergic response -- acute immediate hypersensitivity, anaphylaxis c) major secretory mediator of allergy H1 receptors: --Smooth muscle contraction --Increases vascular permeability --Increases prostoglandin production H2 receptors: --Acid mucus secretion increase intracell cAMP --Histamine stored in basophil granules Thrombocytes 2/3 in the circulation, 1/3 reserve in spleen Life span 6-10 days initiate the clotting process by