Project description:Background: T cells expressing antigen-specific chimeric antigen receptors (CARs) improve outcomes for CD19-expressing B-cell malignancies. We provide the first human application of T cells genetically modified using the Sleeping Beauty (SB) transposon/transposase system to express a CD19-specific CAR. Methods: T cells were genetically modified using DNA plasmids from the SB platform to stably express a second-generation CD19-specific CAR and selectively propagated ex vivo with activating and propagating cells (AaPC) and cytokines. Twenty-six patients with advanced NHL and ALL safely underwent hematopoietic stem-cell transplantation (HSCT) and infusion of CAR T cells as adjuvant therapy in the autologous (n=7) or allogeneic settings (n=19). Results: SB-mediated genetic transposition and stimulation resulted in 2,200-2,500-fold ex vivo genetically modified T-cell expansion, with 84% CAR expression, and without integration hotspots. The 30-month progression-free and overall survivals were 83% and 100%, respectively, following autologous HSCT, and the respective 12-month rates after allogeneic HSCT were 53% and 63%. No acute or late toxicities and no exacerbation of graft-versus-host-disease were observed. Despite a low antigen burden and unsupportive recipient cytokine environment, CAR T cells persisted for an average of 201 days for autologous and 51 days for allogeneic recipients. Conclusions: CD19-specific CAR T cells generated with SB and AaPC platforms were safe, and may provide additional cancer control as planned infusions after HSCT, supporting further clinical development of this non-viral gene therapy approach.
Project description:Thymic lymphomas were generated by inducing Sleeping Beauty transposon mutagenesis at different stages of T-cell development. This dataset includes exon array results from 14 tumor samples from two different Sleeping Beauty models of T-ALL (7 Vav-SB and 7 CD4-SB samples).
Project description:Long-Term Follow-Up Study for Subjects Enrolled in the Phase I/II Study of Autologous T Cells Engineered using the Sleeping Beauty System to Express T cell Receptors (TCRs) Reactive Against Cancer-specific Mutations in Subjects with Solid Tumors
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.