• The subjects voluntarily participated in the study and signed the informed consent form.

• Age ≥18 years old and ≤70 years old, both sexes.

• Organ function and laboratory tests:

‣ Liver function: alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤3× upper limit of normal (ULN), total bilirubin (TBIL) ≤2×ULN (except Gilbert's syndrome).

⁃ Renal function: creatinine ≤1.5×ULN or creatinine clearance ≥40 ml/min.

⁃ Blood routine: neutrophil count ≥1×109/L, hemoglobin ≥60g/L, platelet count ≥20×109/L, lymphocyte count \>0.3×109/L.

⁃ Coagulation: international normalized ratio (INR) ≤ 1.5×ULN, or prothrombin time (PT) ≤ 1.5×ULN.

⁃ Oxygen saturation (SpO2) ≥92% at rest in room air.

⁃ Left ventricular ejection fraction (LVEF) ≥50% on echocardiography.

• Negative serum or urine pregnancy test results in female subjects of childbearing potential at screening.

• Women of childbearing potential must agree to use a highly effective method of contraception for at least 28 days before initiation of elution and up to 12 months after RD06-04 reinfusion. Men of childbearing potential had to agree to the use of an effective barrier method of contraception from the initiation of lymphoidectomy until 12 months after reinfusion of RD06-04 and had to refrain from donating semen or sperm throughout the trial.

∙ SLE Patient Inclusion Criteria:

• A definitive diagnosis of SLE according to the 2019 European League Against Rheumatism (EULAR) / American College of Rheumatology (ACR) classification criteria or the 2012 Systemic Lupus International Collaborating Clinics (SLICC) criteria.

• Positive antinuclear antibodies (ANA) at screening, and/or positive anti-double-stranded DNA (anti-dsDNA) antibodies, and/or positive anti-Smith antibodies.

• A SLEDAI-2K score \>6 at screening, and a 'clinical' SLEDAI-2K score ≥4.

∙ SSc Patient Inclusion Criteria:

• Diagnosed with SSc according to the 2013 ACR/EULAR classification criteria.

• Diagnosed with diffuse cutaneous SSc at screening, with a disease duration ≤6 years.

∙ AAV Patient Inclusion Criteria:

• Meeting the diagnostic criteria for ANCA-associated vasculitis established by the 2022 ACR/EULAR, including Microscopic Polyangiitis (MPA), Granulomatosis with Polyangiitis (GPA), and Eosinophilic Granulomatosis with Polyangiitis (EGPA).

• Positive testing for ANCA-associated antibodies 3 months before screening or at screening (specifically, positive anti-myeloperoxidase antibodies, MPO-ANCA, or positive anti-proteinase 3 antibodies, PR3-ANCA).

∙ IIM Patients Inclusion Criteria:

• Diagnosed with IIM according to the 2017 ACR/EULAR classification criteria (including probable or definite diagnosis, i.e., probability ≥55%), including subtypes such as Dermatomyositis (DM), Anti-Synthetase Syndrome (ASS), and Immune-Mediated Necrotizing Myopathy (IMNM).

• Patients in the active phase, defined as those with at least 2 of the following six core set measures being abnormal: decreased muscle strength (MMT-8 \<142), Physician Global Assessment (PhGA, 10cm VAS) ≥2cm, Patient Global Assessment (PtGA, 10cm VAS) ≥2cm, Extramuscular Disease Activity Total Score (assessed using the MDAAT scoring tool) ≥2cm, Health Assessment Questionnaire (HAQ) ≥0.25, and Creatine Kinase (CK) muscle enzyme levels ≥1.5×ULN

∙ Sjögren's Syndrome (SS) Patient Inclusion Criteria:

• Diagnosed with primary Sjögren's Syndrome according to the 2016 ACR/EULAR classification criteria.

• Positive for anti-SSA/Ro antibodies detected 3 months before screening or at screening.

• A score of ≥5 on the European League Against Rheumatism Sjögren's Syndrome Disease Activity Index (ESSDAI) at screening.