Dendritic cell(DC) play an important role in maintaining autoimmunity tolerance.Alterations of DC are likely to be responsible for defective immune regulator mechanisms and imbalance of nature immune tolerance,which resulting in autoimmue disease.besides,the activating of T cells and B cells by DC has close relationship with of the occurrence of autoimmue diseases.so,it is considered that DC is the key position in pathological mechanism of autoimmune disease.Moreover related study of DC in autoimmune disease therapy show its close relationship with antoimmune diseases from anther view.Idiopathic thrombocytopenic purpura(ITP) is the common autoimmune disease of hematological system,the role of DCs in ITP illustrates its significance in autoimmue disease.