Heparin-associated Autoantibodies

Publisher Summary This chapter provides an overview of heparin-associated autoantibodies. The studies include intensive efforts to standardize the assay, define associations with disease or clinical presentation, and characterize antigenic and biological properties of these antibodies Heparin-induced thrombocytopenia (HIT) provides an interesting model of autoimmunity in which a heterologous mucopolysaccharide combines with a normal endogenous protein released in specific clinical settings to generate autoantibodies in susceptible, but immunologically ‘normal” individuals to cause thrombocytopenia and thrombosis. HIT antibodies cause normal platelets to aggregate and secrete serotonin in vitro. The serotonin release assay (SRA) provides a more objective endpoint than platelet aggregation studies that have variable sensitivity and specificity.