CD123+CLL-1 CAR-T Sequential Infusion With CD7 CAR-T and Bridging to Allo-HSCT for Relapsed/Refractory Acute Myeloid Leukemia

Inclusion Criteria: Patients must meet all of the following criteria： * Patients are clinically diagnosed with relapsed or refractory acute myeloid leukemia； * Tumor cells are confirmed to be CD123 or CLL-1 positive by flow cytometry (FCM) or immunohistochemistry, with a positivity rate of no less than 80%； * Patients aged 18 to 75 years (inclusive)； * The expected survival time is more than 3 months from the date of signing the informed consent; * KPS≥80 points; * The functions of vital organs need to meet the following conditions: ①LVEF\>50%，and electrocardiogram is normal; ② Oxygen saturation ≥90%;③ SCr≤2.5ULN；④ALT and AST≤5ULN，TBil≤3ULN； * Subjects intending to conceive must agree to use contraception prior to study enrollment and for six months post-study. In the event of pregnancy or suspected pregnancy, they should promptly notify the investigator. * The subject or guardian understands and signs the Informed Consent Form (ICF). Exclusion Criteria: Any of the following conditions will not be eligible for enrolment in this study: * Within one - year prior to signing the informed consent form, there is a history of heart failure of New York Heart Association (NYHA) class ≥ III, or myocardial infarction, cardiac angioplasty or stent implantation, unstable angina pectoris, or other cardiac diseases with prominent clinical symptoms, or the QTc interval is \> 480 ms during screening (the QTc interval is calculated by the Fridericia formula); * Those with active GvHD or t…