[Advances in immunological aspects of idiopathic thrombocytopenic purpura].

Idiopathic thrombocytopenic purpura(ITP) is an autoimmune disease characterized by increased platelet destruction caused by anti-platelet autoantibodies, which mainly target a platelet surface antigen, GP IIb-IIIa. CD4+ T cells reactive with GP IIb-IIIa play a primary role in the disease process, since these autoreactive T cells are involved in the production of pathogenic anti-platelet autoantibodies. GP IIb-IIIa-reactive T cells mainly recognize 'cryptic' determinants on the amino-terminal extracellular domains of both GP IIb alpha and GP IIIa, and are activated primarily in the spleen. These findings are particularly useful for clarifying the pathogenic process in ITP patients and for developing a therapeutic approach that blocks pathogenic anti-platelet antibody production.