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==='''Promotion of phagocytosis'''===
 
==='''Promotion of phagocytosis'''===
* Phagocytes hace receptors for the Fc portion of antibody
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Antibodies also have a function to facilitate phagocytosis. Phagocytes have receptors for the Fc portion of antibody, using FcR receptors. FcR bind the Fc portion of antibody on antigen/antibody complexes, although the antibody alone does not interact with FcRInteraction of FcR with Ab/Ag complexes stimulates '''cellular activation''' which greatly increases the efficiency of phagocytosis. This process is called '''opsonisation'''. Opsonisation promotes the '''production of intracellular enzymes''' and therefore promotes the killing and digestion of internalised micro organisms. Systems used by phagocytes that are important in intracellular killing include free radicals such as oxygen and chlorine, hydrogen peroxidase and nitric oxide produced by nitric oxide synthase. Ultimately phagocytes undergo '''degranulation''' resulting in the '''secretion of certain enzymes and cytotoxic molecules'''. These systems are also activated by the interferons, especially the immune interferon – IFN & gamma. Antibody-mediated opsonisation of micro organisms is much more efficient that innate immune system receptors. Phagocytes also have receptors for iC3b, a [[Complement|complement]] component which is also a major initiator of opsonisation.
** Fc receptors - FcR
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* FcR bind the Fc portion of antibody on antigen/antibody complexes
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** Antibody alone does not interact with FcR
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* Interaction of FcR with Ab/Ag complexes stimulates:
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** '''Cellular activation'''
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*** Causes greatly increased efficiency of phagocytosis - '''opsonisation'''
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** '''Production of intracellular enzymes'''
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*** Promotes the killing and digestion of internalised micro organisms
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*** Systems important in intracellular killing include:
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**** Free radicals
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***** Oxygen and chlorine free radicals
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**** Hydrogen peroxidase
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**** Nitric oxide
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***** Produced by nitric oxide synthase
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** '''Secretion of certain enzymes and cytotoxic molecules'''
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** '''The degranulation of phagocytes'''
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* These systems are also activated by the interferons, especially the immune interferon – IFN&gamma;
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* Antibody-mediated opsonisation of micro organisms is much more efficient that innate receptors
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* Phagocytes also have receptors for iC3b, a [[Complement|complement]] component
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** A major initiator of opsonisation
      
==='''Degranulation of [[Mast Cells|mast cells]]/ [[Eosinophils|eosinophils]]'''===
 
==='''Degranulation of [[Mast Cells|mast cells]]/ [[Eosinophils|eosinophils]]'''===
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