RecruitingBiological interventionExploratory Clinical Study of Anti-CD19/BCMA Universal CAR-T Cell Injection for the Treatment of Refractory Autoimmune DiseasesA single arm, open-label pilot study is designed to determine the safety and effectiveness of anti-CD19/BCMA-UCAR-T cells in patients with autoimmune diseases. 36-72 patients are planned to be enrolled in the dose-escalation trial.