Inclusion Criteria:

• 1. Age ≥18 years
• 2. Clinical diagnosis of SLE according to 2019 European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) classification criteria
• 3. Biopsy-proven proliferative LN Class III or IV according to 2018 International Society of Nephrology/Renal Pathology Society (ISN/RPS) criteria
• 4. Positive anti-nuclear antibody (ANA) (titer ≥1:80 ), anti-dsDNA (≥30 IU/mL on enzyme-linked immunosorbent assay \[ELISA\]), or anti-Smith at screening or by documented medical history
• 5. Up to date on recommended vaccinations, including against coronavirus disease 2019 (COVID-19)/ severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2), per Centers for Disease Control and Prevention (CDC) or institutional guidelines for immune compromised individuals

Exclusion Criteria:

• 1. Rapidly progressive glomerulonephritis; history of or currently active severe central nervous system (CNS) lupus, including cerebritis, cerebrovascular accident, and seizures
• 2. Prior treatment with cellular immunotherapy (CAR-T) or gene therapy product directed at any target
• 3. History of allogeneic or autologous stem cell transplant
• 4. Evidence of active hepatitis B or hepatitis C infection
• 5. Positive serology for HIV
• 6. Primary immunodeficiency
• 7. History of splenectomy
• 8. History of stroke, seizure, dementia, Parkinson's disease, coordination movement disorder, cerebellar diseases, psychosis, paresis, aphasia, and any other neurologic disorder investigator considers would increase the risk for the subject
• 9. Impaired cardiac function or clinically significant cardiac disease
• 10. Previous or concurrent malignancy with the following exceptions:
• 1. Adequately treated basal cell or squamous cell carcinoma (adequate wound healing is required prior to screening)
• 2. In situ carcinoma of the cervix or breast, treated curatively and without evidence of recurrence for at least 3 years prior to screening
• 3. A primary malignancy which has been completely resected, or treated, and is in complete remission for at least 5 years prior to screening