IL2 and systemic lupus erythematosus: This study has confirmed that the imbalance between Th17 cells and Treg cells caused by the significant reduction of Treg cells may be one of the major causes of SLE and modulating this balance via low-dose IL2 combined with rapamycin is a potential approach for treating SLE since it led to improvements in disease activity and reduction in prednisolone dosage in refractory SLE patients.