The Alteration of Macrophage Function in the Spleen Tissues From Patients With Primary Immune Thrombocytopenia

Inclusion Criteria: * adult ITP patients whose platelet counts remain less than 10 x 10\^9/L * patients whose platelet counts remain less than 30 x 10\^9/L and who continue to experience excessive bleeding after 4 to 6 weeks of appropriate medical treatment * patients who have experienced a transient response to primary treatment and have platelet counts less than 30 x 10\^9/L after 3 months * require continuous glucocorticoid therapy to maintain safe platelet counts * Willing and able to sign written informed consent. Exclusion Criteria: * Received chemotherapy or anticoagulants or other drugs affecting the platelet counts within 3 months before the screening visit. * Current HIV infection or hepatitis B virus or hepatitis C virus infections. * Severe medical condition (lung, hepatic or renal disorder) other than chronic ITP. Unstable or uncontrolled disease or condition related to or impacting cardiac function (e.g., unstable angina, congestive heart failure, uncontrolled hypertension or cardiac arrhythmia) * Female patients who are pregnant. * Have a known diagnosis of other autoimmune diseases, established in the medical history and laboratory findings with positive results for the determination of antinuclear antibodies, anti-cardiolipin antibodies, lupus anticoagulant or direct Coombs test. * Patients who are deemed unsuitable for the study by the investigator.