Development of a Wilms' tumor antigen-specific T-cell receptor for clinical trials: engineered patient's T cells can eliminate autologous leukemia blasts in NOD/SCID mice

Abstract

The online version of this article has a supplementary appendix. BackgroundThe Wilms' tumor antigen (WT1) is an attractive target for immunotherapy of leukemia. In the past, we isolated and characterized the specificity and function of a WT1-specific T-cell receptor. The goal of this translational study was to develop a safe and efficient WT1-T-cell receptor retroviral vector for an adoptive immunotherapy trial with engineered T cells. Design and MethodsWe generated a panel of retroviral constructs containing unmodified or codon-optimized WT1-T-cell receptor α and β genes, linked via internal ribosome entry sites or 2A sequences, with or without an additional inter-chain disulfide bond in the T-cell receptor constant domains. These constructs were functionally analyzed in vitro, and the best one was tested in an autologous primary leukemia model in vivo. ResultsWe identified a WT1-T-cell receptor construct that showed optimal tetramer staining, antigen-specific cytokine production and killing activity when introduced into primary human T cells. Fresh CD34 + cells purified from a patient with leukemia were engrafted into NOD/SCID mice, followed by adoptive immunotherapy with patient's autologous T cells transduced with the WT1-T-cell receptor. This therapeutic treatment evidently decreased leukemia engraftment in mice and resulted in a substantial improvement of leukemia-free survival. ConclusionsThis is the first report that patient's T cells, engineered to express the WT1-T-cell receptor, can eliminate autologous leukemia progenitor cells in an in vivo model. This study provides a firm basis for the planned WT1-T-cell receptor gene therapy trial in leukemia patients. Haematologica. 2010; 95.126-134. doi:10.3324/haematol.2009 This is an open-access paper. Development of a Wilms' tumor antigen-specific T-cell receptor for clinical trials: engineered patient's T cells can eliminate autologous leukemia blasts in NOD/SCID mice

Immunotherapy with TCR-Redirected T Cells: Comparison of TCR-Transduced and TCR-Engineered Hematopoietic Stem Cell–Derived T Cells

“…For example, increased surface expression of the transgenic TCR was achieved by codon optimization of the TCR genes (15). Also, improved transgene cassettes in which TCR a-and b-chain genes are linked by 2A peptides instead of an internal ribosomal entry site confer improved TCR function (16,17). Exchange of amino acids in the C region of human TCR chains by their murine counterpart likewise improved expression of the transgenic TCR and increased avidity of the engineered T lymphocytes (18)(19)(20).…”

Allogeneic HLA-A*02–Restricted WT1-Specific T Cells from Mismatched Donors Are Highly Reactive but Show Off-Target Promiscuity

“…T cells recognizing self-antigens (such as WT1) that are overexpressed in malignant cells are thought to contribute to antitumor reactivity after hematopoietic stem cell transplantation for the treatment of leukemia (5-7) and have therefore been explored for use in adoptive cell therapy (8)(9)(10)(11) and TCR gene transfer (12)(13)(14). Several immunogenic peptides derived from the WT1 protein have been characterized in the context of three different HLA class I molecules (HLA-A*01, HLA-A*02, and HLA-A*24), and T cell responses against these peptides have been described (8,11,(15)(16)(17)(18)(19).…”

T-cell receptor gene transfer for the treatment of leukemia and other tumors

“…In this issue of the journal, Stauss et al 5 describe the development of a safe and efficient WT1-specific TCR for adoptive immunotherapy. In this translational study WT1-TCR-engineered patient's T cells were able to eliminate autologous leukemia progenitor cells in an in vivo model.…”

“…3 In addition, redirected human T cells prevented engraftment of a leukemia cell line as well as autologous primary leukemic cells in NOD/SCIDmice. 4,5 TCR gene modification of T cells as adoptive immunotherapy for cancer patients has progressed significantly in recent years, with two clinical studies using TCR-modified T cells as cellular immunotherapy in patients with metastatic melanoma. 6,7 These studies, performed by the group of S. Rosenberg, demonstrated the feasibility of clinical implementation of TCR gene therapy.…”