This is an investigator initiated, single-arm, open-label, dose-escalation study to explore the preliminary efficacy, safety, tolerability, pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of the universal STAR-T cell injection which is a CD19 and BCMA bispecific CAR-T cells in patients with autoimmune kidney diseases. Approximately 10-24 adult participants diagnosed as IgA nephropathy and primary membranous nephropathy will be enrolled. Three dose levels (1.5 E6 STAR-T cells/kg, 3.0 E6 STAR-T cells/kg and 4.5 E6 STAR-T cells/kg) will be established in this study, and the universal STAR-T cell will be administered as a single intravenous infusion. A recommended dose will be selected for subsequent dose-expansion studies to evaluate the safety and efficacy of universal STAR-T cell injection in participants with autoimmune kidney diseases based on the safety, PK results, and preliminary efficacy data. This study includes the screening period (D-28 to D-6), pre-clearance treatment and observation period (D-5 to D-1), cell infusion and main study endpoint observation period (D0 to W12 after infusion), and extended follow-up period (W12 to W104).