The treatment process of CAR‐T cells involves obtaining T cells from patients, expressing CAR with specific binding to tumor antigen in T cells, infusing expanded CAR‐T cells back into the patients, and monitoring CAR‐T treatment responses.[7] CAR‐T cell manufacturing requires isolating autologous T cells from patients' peripheral blood mononuclear cells (PBMCs) and infecting them with lentivirus expressing CAR with specific binding to tumor antigens, such as CD19, CD20, and CD22. The gene discussed is CD19; the disease is neoplasm.