Screening patients who meet the criteria for peripheral blood mononuclear cell (PBMC) isolation and cell preparation. Based on the status of cell preparation and mutual agreement between the researcher and the participant, the date of reinfusion (Day 0) is determined. From Day -5 to Day -3, the participant receives a conditioning regimen with cyclophosphamide and antithymocyte globulin. After recovery for two days (Day -2 and Day -1), on Day 0, the participant receives reinfusion of BZE2203 (dose determined according to the dose-escalation requirements). The safety observation period lasts for 28 days, and clinical efficacy is assessed from Day 28 to Day 34. After comprehensive judgment, the second course of cell therapy is selected. Follow-up observations and evaluations are conducted once every three months, with follow-up visits once a year and telephone follow-ups once every two months.