Inclusion Criteria:
1. All patients fulfilled the American College of Rheumatology (ACR) criteria of SLE, man or woman aged from 15 to 70 years old, SLEDAI≥8;
2. Lupus nephritis with 24h urine protein≥1g;
3. Refractory disease as determined by failure of the following regimens:
Trial of corticosteroids (oral prednisone more than 20 mg/day); Trial of cyclophosphamide 0.4 \~ 0.6 / m2 every two weeks for six months, or other immunosuppressive drugs, such as mycophenolate mofetil 2 g / day, for three months;
4. Patients must sign an informed consent indicating that they are aware of the investigational nature of the study in keeping with the policy of the hospital;
5. Willing to use contraception throughout the study and for 12 months following treatment
