To investigate the safety and efficacy of umbilical cord mesenchymal stem cell transplantation in patients with systemic lupus erythematosus (SLE) and lupus nephritis (LN).

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease. Lupus nephritis (LN) is one of the most serious complications of SLE. The current clinical treatments of LN mainly include steroids and immunosuppressive drugs, but drug side effects are obvious.

Inclusion Criteria:

• Meeting the 1997 American College of Rheumatology (ACR) classification criteria of SLE.
• age 18-60 years.
• of either sex and of any ethnicity.
• Lupus nephritis (LN) group: (1) Receiving more than 6 months of regular treatment, 24-hour urine protein ≥ 1.0 g, serum creatinine ≥1.5 mg/dL; (2) renal biopsy: class III, IV or V LN included, and class VI excluded.
• After conventional treatment (glucocorticoid therapy and immunosuppressive drugs) prior to grouping, SLEDAI scores ≥ 10.
• Receiving 12 months of treatment while using birth control.
• Provision of informed consent.

Exclusion Criteria:

• Poor blood pressure control by drug treatment (≥ 160/100 mmHg)
• Abnormal hepatic function (a 3-fold increase in alanine aminotransferase level relative to normal liver).
• Renal failure (glomerular filtration rate < 15 mL/min/1.73 m2).
• Severe heart and lung failure, or injury to other important organs
• Uncontrollable infection.
• Having not taken biological agents for 6 months.
• Pregnant or lactating women, or those women who are trying to get pregnant or those men who are trying to make their partners pregnant.