CD19/BCMA UCAR-T for B Cell-Related Autoimmune Disease

Inclusion Criteria: * Common Inclusion Criteria: * 1.Major organ function must meet the following criteria (exceptions allowed for abnormalities related to autoimmune disease activity): 1. Bone Marrow Function: a. Absolute neutrophil count (ANC) ≥ 1.0 × 10⁹/L; b. Hemoglobin ≥ 60 g/L; c. Platelet count ≥ 30 × 10⁹/L. 2. Hepatic Function: ALT ≤ 3 × ULN (except when elevation is attributable to inflammatory myopathy); AST ≤ 3 × ULN (except when elevation is attributable to inflammatory myopathy); Total bilirubin ≤ 2.0 × ULN (≤ 3.0 × ULN allowed for Gilbert syndrome). 3. Renal Function: eGFR ≥ 30 mL/min/1.73 m².(Participants with eGFR \< 30 mL/min/1.73 m² and/or those receiving renal replacement therapy may be considered eligible if, in the investigator's judgment, the potential benefit outweighs the risk and the participant or guardian provides fully informed consent.) 4. Cardiac Function: Echocardiography shows no significant structural abnormalities and left ventricular ejection fraction (LVEF) ≥ 55%. 5. Pulmonary Function: No severe pulmonary disease, and SpO₂ ≥ 92%. * 2.Women of childbearing potential must use medically acceptable contraception or practice abstinence during the study treatment period and for at least 12 months after the end of study treatment. * 3.Informed consent: The participant (and guardian if the participant is a minor) must provide written informed consent, indicating understanding of the study purpose and procedures and willingness to participate. * Disease-Specific Inclusion Criteria * SLE: * 1.Age ≥ 5 years. * 2.Meets the 2012 SLICC or 2019 EULAR/ACR classification criteria for SLE. * 3.Must meet at least one of the following adequate treatment conditions: 1. Active disease persists despite adequate treatment with glucocorticoids (≥1 mg/kg/day prednisone or equivalent dose of other corticosteroids) in combination with at least two immunosuppressants or biologic agents for at least 3 months, or affected organ function has failed to improve; or inability to taper glucocorticoid dosage to ≤5 mg/day after 6 months of conventional treatment; 2. Patients who have developed intolerable drug toxicity during conventional therapy, or have contraindications precluding standard treatment, or have experienced multiple treatment failures-may be considered for enrollment following full informed consent by the investigator and the patient or legal guardian; 3. SLEDAI-2K Criteria: SLEDAI-2K score ≥8; or SLEDAI-2K score ≥6 combined with at least one BILAG-2004 Category A or two Category B organ system involvements (or both)；Patients with severe refractory SLE-ITP, characterized by a platelet count of \<30×10⁹/L or \<50×10⁹/L accompanied by bleeding tendency, regardless of the SLEDAI-2K score. * 4.No occurrence of macrophage activation syndrome within 1 month prior to screening. * 5.Occurrence of CNS lupus symptoms requiring intervention within 60 days prior to screening, including seizures, psychosis, cerebrovascular events, etc. * MDR-SRNS * 1.Age ≥3 years old, gender unlimited. * 2.Diagnosed with SRNS according to the 2021 Kidney Disease: Improving Global Outcomes #KDIGO# Guidelines; * 3\. Must meet at least one of the following adequate treatment conditions: 1. have not achieved a complete response after 12 months of treatment with two standard doses of hormone replacement drugs with different mechanisms of action or relapse of disease activity after remission(at least one of the two drugs is a calcineurin inhibitor such as cyclosporine or tacrolimus, Other replacement drugs include Mycophenolate Mofetil, cyclophosphamide, Telitacicept or rituximab). 2. if no remission has been achieved after 3 to 6 months of adequate treatment with one calcineurin- inhibitor. The researcher judges that the benefits outweigh the risks and the patient or guardian has fully informed consent, the patient can be considered for inclusion. 3. Patients unable to tolerate conventional therapy may be eligible if, in the investigator's judgment, the potential benefit outweighs the risk and the participant (or guardian if minor) provides fully informed consent. 4. Patients with other diseases, such as systemic lupus erythematosus, requiring long-term systemic treatment with glucocorticoids or immunosuppressants, may be considered for inclusion after the investigator determines that the benefits outweigh the risks, and the patient or guardian has fully informed consent. * 4.Renal biopsy was performed and the pathological type was determined to be minimal lesion nephropathy(MCD) or focal segmental glomerulosclerosis (FSGS); * IgA nephropathy * 1\. Age: ≥ 5 years old, gender unlimited; * 2\. IgA nephropathy pathologically confirmed by renal biopsy; * 3\. Angiotensin-Converting Enzyme Inhibitors (ACEI) or angiotensin receptor blocker (ARB) treated for at least 3 months and meet at least one of the following requirements: 1. Combination or sequential treatment with steroids and at least one immunosuppressant or biologic for ≥ 3 months; and 24-hour urine protein quantification ≥500mg or UPCR≥0.5mg/mg; 2. \>50% decline in eGFR within 3 months; 3. Patients who are unable to tolerate conventional treatment and for whom the investigator determines the benefits outweigh the risks and who have obtained fully informed consent from the patient or guardian may be considered for inclusion; * 4\. Exclude subjects with other secondary causes; exclude patients with uncontrolled blood pressure. * Systemic Sclerosis: * 1\. Age: ≥ 5 years old, gender unlimited; * 2\. Scleroderma fulfilling the 2013 ACR classification criteria * 3\. Positive scleroderma-related antibodies. * 4\. Modified Rodnan Skin Score (mRSS) ≥ 15 (total score 51). * 5\. Must meet at least one of the following adequate treatment conditions: 1. Treated with glucocorticoids (≥0.5 mg/kg/day) plus at least one immunomodulatory agent (including antimalarials, cyclophosphamide, azathioprine, mycophenolate mofetil, methotrexat