Arthrus reactions

Type III reactions are the result of antigen-antibody (IgG or IgM) complexes that accumulate in tissues or the circulation, activate macrophages and the complement system, and trigger the influx of granulocytes and lymphocytes (inflammation). Examples include an Arthrus reaction when soluble antigen is injected into the skin of a sensitized individual and serum sickness, which occurs 7 to 10 days following the administration... 

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