Dual Target CAR-T Cell Treatment for Refractory Systemic Lupus Erythematosus (SLE) Patients

Inclusion Criteria: 1. 18-70 years old; 2. Total score ≥ 10 on the EULAR/ACR 2019 SLE classification criteria; 3. LLDAS response criteria are not achieved after administration with at least two immunosuppressants (including, but not limited to, azathioprine, mycophenolate mofetil, cyclophosphamide, methotrexate, leflunomide, tacrolimus, ciclosporin and iguratimod) and/or at least one approved biological agent for more than 6 months. 4. SELENA-SLEDAI≥8; 5. Patients with CD19+ B-cell; 6. Hemoglobin≥85 g/L; 7. WBC≥2.5×10\^9/L 8. NEUT≥1×10\^9/L; 9. BPC≥50×10\^9/L; 10. AST/ALT below 2 times the upper limit of normal; Creatinine clearance ≥30 mL/min; blood bilirubin ≤2.0 mg/dl; echocardiography indicates that the ejection fraction is ≥50%; 11. Adequate venous access for apheresis, and no other contraindications for leukapheresis; 12. Women of childbearing age should have a negative serum or urine pregnancy test at screening and baseline. Subjects agree to take effective contraceptive measures during the trial until at least 1 year after CAR-T cells infusion. 13. Agree to attend follow-up visits as required; 14. Voluntary participation and informed consent signed by the patient or his/her legal/authorized representative; Exclusion Criteria: 1. Renal disease: severe lupus nephritis (serum creatinine \> 2.5 mg/dL or 221 μmol/L) within 8 weeks prior to leukapheresis, or subjects who need hemodialysis; 2. CNS disease: including epilepsy, psychosis, organic encephalopathy syndrome, cerebrovascular accident \[CVA\], encephalitis or CNS vasculitis, psychiatric patients with depression or suicidal thoughts; 3. Patients with serious lesions and history of present illness of vital organs such as heart, liver, kidney and blood and endocrine system; 4. Patients with immunodeficiency, uncontrolled active infections and active or recurrent peptic ulcers; 5. Received immunosuppressive therapy within 1 week prior to leukapheresis; 6. Patients with HIV infection; Active infection of hepatitis B virus or hepatitis C virus; Patients with syphilis infection; 7. The presence or suspicion of an active fungal, bacterial, viral or other infection that cannot be controlled during screening; 8. Received live vaccine treatment within 4 weeks prior to screening; 9. Severe allergies or hypersensitivity; 10. Contraindication to cyclophosphamide in combination with fludarabine; 11. Subjects who have undergone major surgery within 2 weeks prior to signing the informed consent form, or who are scheduled to have surgery (other than local anesthetic surgery) during the trial or within 2 weeks of the infusion; 12. cannula or drainage tubes other than central venous catheters; 13. Pregnant or lactating women, or subjects who plan to have children within 1 year of treatment; 14. Subjects with prior CD19 or BCMA-targeted therapy 15. Participated in any clinical study within 3 months prior to enrollment 16. Subjects with malignant tumour, except for Non-melanoma Skin Cancer with PFS\>5yr; Cervical Cancer in situ; Bladder Cancer; Breast Cancer; 17. Any situations that the investigator believes the patients are not suitable for the study.