Although CAR-T therapy for non-B-cell leukemia still faces great challenges, researchers are already exploring multiple therapeutic targets, with promising results in preclinical and clinical studies, such as with CD7, CD5, CD4, and other targets in T-ALL that overcome CAR-T-cell fratricide, tumor cell contamination and T-cell immunodeficiency. The gene discussed is CD7; the disease is T-cell immunodeficiency.