A Clinical Study of CD19 CAR NK Cells for the Treatment of Relapsed/Refractory B-cell Related Autoimmune Diseases

Inclusion Criteria:

1. Subjects voluntarily participate in this clinical study and sign the InformedConsent Form (ICF) and are willing to follow and be able to complete all trialprocedures

2. Subjects disease status of enrolment: not complete response (CR) after standardtreatment; moderately to severely active autoimmune diseases

3. Age: ≥ 18 years old and ≤ 70 years old, male or female

4. Subjects with estimated survival > 12 weeks

5. Adequate organs function: Serum creatinine clearance meets relevant age/sexcriteria,aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 3times the upper limit of normal (ULN)

6. ECOG performance ≤ 2

7. Left ventricular ejection fraction (LVEF) ≥ 45%

8. Subjects have been treated with OCS in combination with an immunosuppressive orbiologic agent for at least 2 weeks prior to enrollment

Exclusion Criteria:

1. Subjects with known severe allergic reactions, hypersensitivity, contraindication toany medications during the trial (cyclophosphamide, fludarabine, tozumabs), orsubjects with a history of severe allergic reactions

2. Subjects with one of the following genetic syndromes: Fanconi syndrome, Kostmannsyndrome, Shwachman syndrome or any of the known bone marrow failure syndromes

3. Subjects with active or uncontrolled infections requiring parenteral antimicrobials;evidence of severe active viral or bacterial infections or uncontrolled systemicfungal infections

4. Subjects with grade III or IV heart failure (NYHA classification)

5. History of epilepsy or other central nervous system (CNS) diseases

6. History of other primary malignant tumors except: cured non-melanoma skin cancer orprimary cervical cancer; subjects with inactive tumors

7. Subjects with more pronounced bleeding tendencies, such as gastrointestinalbleeding, coagulation disorders, and hypersplenism

8. Subjects were treated with systemic corticosteroids concomitantly within 2 weeksprior to treatment

9. Subjects with unstable angina, symptomatic congestive heart failure or myocardialinfarction within the last 6 months

10. Females who are pregnant, lactating, or planning a pregnancy within six months

11. Subjects who have received other clinical trial treatment within 3 months

12. Any situation judged by the investigators that may increase the risk of the subjectsor interfere with the clinical trial outcome