This study is being conducted to assess anti-CD19-CAR-T cells safety and efficacy in treating patients with systemic lupus erythematosus(SLE).The investigators constructed a 2nd CAR, using CD19 as target, using 4-1BB as co-stimulator, and optimized the spatial conformation by a suitable hinge and transmembrane domain sequences. The infusion dose is (1-10)E6 CAR positive T cells/kg, and the specific cells numbers depends on the situation of individual CAR-T cells preparation.