Effective Targeting of Multiple B-Cell Maturation Antigen-Expressing Hematological Malignances by Anti-B-Cell Maturation Antigen Chimeric Antigen Receptor T Cells

Hum Gene Ther. 2018 May;29(5):585-601. doi: 10.1089/hum.2018.001.


B-cell maturation antigen (BCMA) expression has been proposed as a marker for the identification of malignant plasma cells in patients with multiple myeloma (MM). Nearly all MM tumor cells express BCMA, while normal tissue expression is restricted to plasma cells and a subset of mature B cells. Consistent BCMA expression was confirmed on MM biopsies (29/29 BCMA+), and it was further demonstrated that BCMA is expressed in a substantial number of lymphoma samples, as well as primary chronic lymphocytic leukemia B cells. To target BCMA using redirected autologous T cells, lentiviral vectors (LVV) encoding chimeric antigen receptors (CARs) were constructed with four unique anti-BCMA single-chain variable fragments, fused to the CD137 (4-1BB) co-stimulatory and CD3ζ signaling domains. One LVV, BB2121, was studied in detail, and BB2121 CAR-transduced T cells (bb2121) exhibited a high frequency of CAR + T cells and robust in vitro activity against MM cell lines, lymphoma cell lines, and primary chronic lymphocytic leukemia peripheral blood. Based on receptor quantification, bb2121 recognized tumor cells expressing as little as 222 BCMA molecules per cell. The in vivo pharmacology of anti-BCMA CAR T cells was studied in NSG mouse models of human MM, Burkitt lymphoma, and mantle cell lymphoma, where mice received a single intravenous administration of vehicle, control vector-transduced T cells, or anti-BCMA CAR-transduced T cells. In all models, the vehicle and control CAR T cells failed to inhibit tumor growth. In contrast, treatment with bb2121 resulted in rapid and sustained elimination of the tumors and 100% survival in all treatment models. Together, these data support the further development of anti-BCMA CAR T cells as a potential treatment for not only MM but also some lymphomas.

Keywords: BCMA; CAR; adoptive cell therapy; gene therapy; immunotherapy; multiple myeloma.

MeSH terms

  • Animals
  • B-Cell Maturation Antigen / antagonists & inhibitors*
  • B-Cell Maturation Antigen / immunology
  • CD3 Complex / genetics
  • CD3 Complex / immunology
  • Cell Line, Tumor
  • Cytotoxicity, Immunologic / drug effects
  • Gene Expression Regulation, Neoplastic / drug effects
  • Hematologic Neoplasms / genetics
  • Hematologic Neoplasms / immunology
  • Hematologic Neoplasms / pathology
  • Hematologic Neoplasms / therapy*
  • Humans
  • Immunotherapy, Adoptive
  • Lentivirus / genetics
  • Mice
  • Multiple Myeloma / genetics
  • Multiple Myeloma / pathology
  • Multiple Myeloma / therapy*
  • Receptors, Chimeric Antigen / immunology*
  • Receptors, Chimeric Antigen / therapeutic use
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / immunology
  • Tumor Necrosis Factor Receptor Superfamily, Member 9 / genetics
  • Tumor Necrosis Factor Receptor Superfamily, Member 9 / immunology
  • Xenograft Model Antitumor Assays


  • B-Cell Maturation Antigen
  • CD3 Complex
  • CD3 antigen, zeta chain
  • Receptors, Chimeric Antigen
  • Tumor Necrosis Factor Receptor Superfamily, Member 9