Autologous T lymphocytes engineered to express a chimeric antigen receptor that recognizes CD19 on B cells. CAR signaling via CD3ζ and costimulatory domains (e.g., 4-1BB or CD28) upon CD19 binding triggers T-cell activation, proliferation, cytokine release, and perforin/granzyme-mediated cytolysis of CD19-positive malignant B cells, frequently causing B-cell aplasia.