Hypersensitivity reaction seen in immune thrombocytopenic purpura is
Hypersensitivity Reactions Type 2 HSR Associated with Production of IgG, IgMwhich binds to antigen on target cell or tissue. Causing phagocytosis or lysis of target cell by activated complement or Fc receptors; recruitment of leukocytes. ITP is a type 2 HSR. Type 1 HSR Associated with Production of IgE antibodyleading to immediate release of vasoactive amines and other mediators from mast cells; later recruitment of inflammatory cells. Ex: Anaphylaxis; allergies; bronchial asthma Type 3 HSR Deposition of antigen-antibody complexes-complement activation - recruitment of leukocytesby complement products and Fc receptors -release of enzymes and other toxic molecules Ex: SLE, serum sickness, ahus reaction Type 4 HSR Associated with Activated T lymphocytes - (1) release of cytokines, Inflammation and macrophage activation; (2) Tcell-mediated cytotoxicity Ex: Type 1 DM, Contact dermatitis
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Hypersensitivity