7.1.2 Type II
Type II Hypersensitivity (Antibody Mediated Type) 
  • AKA:  cytotoxic type (although not always cytotoxic)
  • Antibodies directed against normal or modified cell surface or tissue components induce cell lysis
  • Complement Dependent
    • Two Mechanisms:
      • Direct lysis by complement activation
      • Lysis by opsonization (C3b) - often involves RBCs
    • Examples: 
      • Transfusion reactions
      • Erythroblastosis fetalis
      • Autoimmune hemolytic anemia
      • Autoimmune thrombocytopenia
      • Certain drug reactions
  • Antibody-Dependent Cell-Mediated Cytotoxicity
    • Monocytes, neutrophils, eosinophils, or NK cells recognize cells by Fc portion of IgG bound to cell and kill cell without phagocytosis
    • Example:  Goodpasture's syndrome
  • Anti-Receptor Antibodies
    • Noncytotoxic
    • Examples:  myasthenia gravis from antibody to acetylcholine receptor
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