Novel CD37, Humanized CD37 and Bi-Specific Humanized CD37-CD19 CAR-T Cells Specifically Target Lymphoma

Abstract

CD19 and CD37 proteins are highly expressed in B-cell lymphoma and have been successfully targeted with different monotherapies, including chimeric antigen receptor (CAR)-T cell therapy. The goal of this study was to target lymphoma with novel CD37, humanized CD37, and bi-specific humanized CD37-CD19 CAR-T cells. A novel mouse monoclonal anti-human CD37 antibody (clone 2B8D12F2D4) was generated with high binding affinity for CD37 antigen (KD = 1.6 nM). The CD37 antibody specifically recognized cell surface CD37 protein in lymphoma cells and not in multiple myeloma or other types of cancer. The mouse and humanized CD37-CAR-T cells specifically killed Raji and CHO-CD37 cells and secreted IFN-gamma. In addition, we generated bi-specific humanized hCD37-CD19 CAR-T cells that specifically killed Raji cells, CHO-CD37, and Hela-CD19 cells and did not kill control CHO or Hela cells. Moreover, the hCD37-CD19 CAR-T cells secreted IFN-gamma against CD37-positive and CD19-positive target CHO-CD37, Hela-CD19 cells, respectively, but not against CD19 and CD37-negative parental cell line. The bi-specific hCD37-CD19 significantly inhibited Raji xenograft tumor growth and prolonged mouse survival in NOD scid gamma mouse (NSG) mouse model. This study demonstrates that novel humanized CD37 and humanized CD37-CD19 CAR-T cells specifically targeted either CD37 positive or CD37 and CD19-positive cells and provides a basis for future clinical studies.

Systematic Review of Available CAR-T Cell Trials around the World

“…However, these phenomena are not enough to trigger an effective anti-tumor response in most patients. Therefore, bi-specific CAR-T cells that can recognize more than one target-antigen are being studied to circumvent this issue [ 40 , 41 ]. Second-generation CAR are the most explored constructs, especially for hematological malignancies, followed by fourth- and third-generation constructs.…”

Novel CS1 CAR-T Cells and Bispecific CS1-BCMA CAR-T Cells Effectively Target Multiple Myeloma

“…The CAR was in subcloned into a third-generation lentivirus under either EF1 (with CD28 costimulatory domain CAR) or MNDU3 promoter (with 41BB costimulatory domain CAR). Mock CAR-T cells with extracellular TF tag-CD28-CD3 CAR-T cells were used as Mock CAR-T cells [24,30].…”

“…Based on their high percentage of expression in multiple myeloma, both targets are used for CAR-T cell therapy [19][20][21][22]. One of the challenges is that BCMA can be downregulated or lost, causing resistance to this treatment; thus, novel CAR-T cells and bi-specific CAR-T cells need to be developed for effective therapy of multiple myeloma similarly to bispecific CD19-CD22, CD19-CD20, CD19-CD37, and other state-of-the art CAR-T cells developed against leukemia [23][24][25][26][27][28]. This report aimed to develop novel CS1-CAR-T cells and bispecific CS1-BCMA-CAR-T cells against multiple myeloma.…”

Editorial on Special Issue “Immunotherapy, Tumor Microenvironment and Survival Signaling”

“…One of the approaches to overcome potential CD19 loss during treatment with CD19 CAR-T cells was presented in a paper with novel CD37 and CD37-CD19-CAR-T cells [ 6 ]. The authors generated a novel CD37 antibody and engineered both novel Cd37-CAR-T cells and bispecific CD37-CD19-CAR-T cells that effectively targeted CD19+CD37+ lymphoma in vitro and in vivo [ 6 ].…”