This study is an open, single-center, prospective clinical trial, with newly diagnosed high-risk T-LBL/ALL patients as the subjects. It plans to enroll 10 subjects. All patients will undergo lymphocyte collection during the CR1 remission period, followed by the preparation and reinfusion of CD7 CAR-T cells. Adverse reactions will be followed up and observed, and relevant data on treatment efficacy will be collected to evaluate the safety, efficacy, and cell metabolic kinetics characteristics of CAR-T cell therapy for the patients.

Inclusion Criteria:

• Patients aged ≤18 years with newly diagnosed T-LBL/ALL.
• Have completed induction chemotherapy and achieved CR1, with bone marrow MRD < 0.01%.
• High/very high-risk or poor induction response patients.
• High risk of future relapse, and recommended by multidisciplinary team (MDT) evaluation for prospective lymphocyte collection and preparation.
• Peripheral blood absolute lymphocyte count (ALC) ≥ 0.5×10⁹/L, and good general condition (ECOG score 0-1 or Lansky/Karnofsky score ≥ 80).
• Legal guardian agrees to provide written informed consent.

Infusion Criteria:

• Essential normal function of major organs.
• Left ventricular ejection fraction (LVEF) ≥ 45%.
• Serum creatinine ≤ 1.5 × upper limit of normal (ULN) for age.
• Serum total bilirubin, ALT/AST ≤ 3 × ULN (unless clearly related to leukemic infiltration).
• No active, uncontrolled severe infection.

Exclusion Criteria:

• Severe cardiac or pulmonary insufficiency, which the investigator deems inappropriate for enrollment.
• Complicated with other progressive malignant tumors.
• Presence of active and/or uncontrolled infections that have not been effectively managed.
• Complicated with severe autoimmune diseases or congenital immunodeficiency.
• Active hepatitis [positive for hepatitis B surface antigen (HBsAg) and/or hepatitis B core antibody (HBcAb), with HBV DNA copy number greater than the upper limit of normal at the study center; positive for anti-HCV, with HCV-RNA copy number greater than the upper limit of normal at the study center].
• Human immunodeficiency virus (HIV) infection or known acquired immune deficiency syndrome (AIDS), syphilis infection.).
• A history of severe hypersensitivity to biological products (including antibiotics).
• Patients who have undergone allogeneic hematopoietic stem cell transplantation and still suffer from acute graft-versus-host disease (GVHD) one month after discontinuation of immunosuppressive agents.
• Patients with other severe physical or mental diseases or abnormal laboratory test results that may increase the risk of study participation or interfere with study outcomes, as well as those who are deemed unsuitable for participation in this study by the investigator.