• 1\. Age≥ 18 years old, regardless of gender. 2. Clinical diagnosis of primary immune thrombocytopenia for at least 6 months, platelet count \< 30×10\^9/L within 48 hours before participating in the study.

• 3\. Positive anti-platelet glycoprotein autoantibodies (such as GPIIb/IIIa). 4. Prior second-line ITP therapy (first-line treatment includes: corticosteroids or immunoglobulins; Second-line therapies include thrombopoietin receptor agonists (eg, eltrombopag, romiplostim) and/or rituximab, but are ineffective (platelet count \< 30×10\^9/L after treatment, or platelet count does not increase twice as much as baseline, or there is bleeding), or relapse after effective treatment (platelet count falls below 30×109/L after effective treatment, or falls below baseline, or bleeding symptoms) or is difficult to maintain after discontinuation of TPO agonists.

• 5\. Bone marrow examination shows megakaryocytosis or normal. 6. Basic normal functions of important organs:Echocardiography shows an ejection fraction of ≥50% and no significant abnormalities on ECG.Creatinine clearance (CrCl) (Cockcroft-Gault formula) ≥ 30 mL/min.Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 3.0 × upper limit of normal (ULN).Total bilirubin (TBIL) and alkaline phosphatase (AKP or ALP) ≤ 2.0× ULN (Gilbert's syndrome ≤3.0×ULN).Absolute lymphocyte count (ALC) ≥ 0.5×10\^9/L; Absolute neutrophil count (ANC) ≥1×10\^9/L; Hemoglobin (Hb) ≥ 60 g/L; Platelet count ≥ 10×10\^9/L.Oxygen saturation \> 92%.ECOG performance status ≤2 7. Males and women of childbearing potential must agree to use effective contraception from the time of signing the informed consent form until 1 year after the use of the study drug. Women of childbearing potential must have a negative blood pregnancy test at screening and prior to drug infusion and must not be breastfeeding.