ABSTRACT
The outlook for T-cell malignancies remain poor due to the lack of effective therapeutic options. Chimeric antigen receptor (CAR) immunotherapy has recently shown promise in clinical trials for B-cell malignancies, however, designing CARs for T-cell based disease remain a challenge due to the shared surface antigen pool between normal and malignant T-cells. Normal T-cells express CD5 but NK (natural killer) cells do not, positioning NK cells as attractive cytotoxicity cells for CD5CAR design. Additionally, CD5 is highly expressed in T-cell acute lymphoblastic leukemia (T-ALL) and peripheral T-cell lymphomas (PTCLs). Here, we report a robust anti-CD5 CAR (CD5CAR) transduced into a human NK cell line NK-92 that can undergo stable expansion ex vivo. We found that CD5CAR NK-92 cells possessed consistent, specific, and potent anti-tumor activity against a variety of T-cell leukemia and lymphoma cell lines as well as primary tumor cells. Furthermore, we were able to demonstrate significant inhibition and control of disease progression in xenograft mouse models of T-ALL. The data suggest that CAR redirected targeting for T-cell malignancies using NK cells may be a viable method for new and complementary therapeutic approaches that could improve the current outcome for patients.
Subject(s)
Antigens, Neoplasm/immunology , CD5 Antigens/immunology , Immunotherapy, Adoptive/methods , Killer Cells, Natural/immunology , Lymphoma, T-Cell, Peripheral/therapy , Molecular Targeted Therapy , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/therapy , Recombinant Fusion Proteins/immunology , 4-1BB Ligand/genetics , 4-1BB Ligand/immunology , Animals , CD28 Antigens/immunology , CD3 Complex/genetics , CD3 Complex/immunology , CD8 Antigens/immunology , Cell Line, Tumor , Coculture Techniques , Cytotoxicity, Immunologic , Humans , Killer Cells, Natural/transplantation , Lymphoma, T-Cell, Peripheral/pathology , Mice , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/pathology , Salvage Therapy , Single-Chain Antibodies/genetics , Single-Chain Antibodies/immunology , Transduction, Genetic , Tumor Necrosis Factor Receptor Superfamily, Member 9/immunology , Xenograft Model Antitumor AssaysABSTRACT
Peripheral T-cell lymphomas (PTCLs) are aggressive lymphomas with no effective upfront standard treatment and ineffective options in relapsed disease, resulting in poorer clinical outcomes as compared with B-cell lymphomas. The adoptive transfer of T cells engineered to express chimeric antigen receptors (CARs) is a promising new approach for treatment of hematological malignancies. However, preclinical reports of targeting T-cell lymphoma with CARs are almost non-existent. Here we have designed a CAR, CD4CAR, which redirects the antigen specificity of CD8+ cytotoxic T cells to CD4-expressing cells. CD4CAR T cells derived from human peripheral blood mononuclear cells and cord blood effectively redirected T-cell specificity against CD4+ cells in vitro. CD4CAR T cells efficiently eliminated a CD4+ leukemic cell line and primary CD4+ PTCL patient samples in co-culture assays. Notably, CD4CAR T cells maintained a central memory stem cell-like phenotype (CD8+CD45RO+CD62L+) under standard culture conditions. Furthermore, in aggressive orthotropic T-cell lymphoma models, CD4CAR T cells efficiently suppressed the growth of lymphoma cells while also significantly prolonging mouse survival. Combined, these studies demonstrate that CD4CAR-expressing CD8+ T cells are efficacious in ablating malignant CD4+ populations, with potential use as a bridge to transplant or stand-alone therapy for the treatment of PTCLs.
