Project description:Precise targeting of large transgenes to T cells using homology-directed repair has been transformative for adoptive cell therapies and T cell biology. Non-toxic delivery of DNA templates via adeno-associated virus (AAV) has greatly improved knock-in efficiencies, but the tropism of current AAV serotypes restricts their use to human T cells employed in immunodeficient mouse models. To enable targeted knock-ins in murine T cells, we evolved Ark313, a synthetic AAV that exhibits high transduction efficiency in murine T cells. We performed a genome-wide knockout screen and identified QA2 as an essential factor for Ark313 infection. We demonstrate that Ark313 can be used for nucleofection-free DNA delivery, CRISPR/Cas9-mediated knockouts, and targeted integration of large transgenes. Ark313 enables pre-clinical modeling of Trac-targeted CAR-T and transgenic TCR-T cells in immunocompetent models. Efficient gene targeting in murine T cells holds great potential for improved cell therapies and opens new avenues in experimental T cell immunology.
Project description:CRISPR-Cas9 delivery by AAV holds promise for gene therapy but faces critical barriers due to its potential immunogenicity and limited payload capacity. Here, we demonstrate genome engineering in postnatal mice using AAV-split-Cas9, a multi-functional platform customizable for genome-editing, transcriptional regulation, and other previously impracticable AAV-CRISPR-Cas9 applications. We identify crucial parameters that impact efficacy and clinical translation of our platform, including viral biodistribution, editing efficiencies in various organs, antigenicity, immunological reactions, and physiological outcomes. These results reveal that AAV-CRISPR-Cas9 evokes host responses with distinct cellular and molecular signatures, but unlike alternative delivery methods, does not induce detectable cellular damage in vivo. Our study provides a foundation for developing effective genome therapeutics mRNA-Seq from muscles (9 samples; 3 mice x 3 conditions) and lymph nodes (9 samples; 3 mice x 3 conditions).
Project description:Engineering microbes with novel metabolic properties is a critical step for production of biofuels and biochemicals. Synthetic biology enables identification and engineering of metabolic pathways into microbes; however, knowledge of how to reroute cellular regulatory signals and metabolic flux remains lacking. Here we used network analysis of multi-omic data to dissect the mechanism of anaerobic xylose fermentation, a trait important for biochemical production from plant lignocellulose. We compared transcriptomic, proteomic, and phosphoproteomic differences across a series of strains evolved to ferment xylose under various conditions.
Project description:Engineering microbes with novel metabolic properties is a critical step for production of biofuels and biochemicals. Synthetic biology enables identification and engineering of metabolic pathways into microbes; however, knowledge of how to reroute cellular regulatory signals and metabolic flux remains lacking. Here we used network analysis of multi-omic data to dissect the mechanism of anaerobic xylose fermentation, a trait important for biochemical production from plant lignocellulose. We compared transcriptomic, proteomic, and phosphoproteomic differences across a series of strains evolved to ferment xylose under various conditions.
Project description:The ability to leverage antibodies to agonize disease relevant biological pathways has the potential to unlock new drug targets for clinical investigation. While antibodies have been successful as antagonists, immune mediators, and targeting agents, they are not readily effective at recapitulating the biological activity of natural ligands. Among the important determinants of antibody agonist activity is the geometry of target receptor engagement. Herein, we describe a novel engineering approach inspired by a naturally occurring Fab-Fab homotypic interaction that constrains IgG in a unique i-shaped conformation. i-shaped antibody (iAb) engineering enables potent intrinsic agonism of five tumor necrosis factor receptor superfamily (TNFRSF) targets. When applied to bispecific antibodies against the heterodimeric IL-2 receptor pair, constrained bispecific IgG formats recapitulate IL-2 agonist activity. Thus, iAb engineering represents a new tool to tune agonist antibody function and this work provides a framework for the development of intrinsic antibody agonists with the potential for generalization across broad receptor classes.
Project description:Simple and efficient delivery of CRISPR genome editing systems in primary cells remains a major challenge. Here, we describe an engineered Peptide-Assisted Genome Editing (PAGE) CRISPR-Cas system for rapid and robust editing of primary cells. PAGE couples a cell-penetrating Cas protein with a cell-penetrating endosomal escape peptide in a 30-minute incubation that yields up to ~98% editing efficiency in primary human and mouse T cells. PAGE provides a broadly generalizable platform for next generation genome engineering in primary cells. CITATION INFORMATION: Zhang Zhen, Baxter Amy E, Ren Diqiu, Qin Kunhua, Chen Zeyu, Collins Sierra M., Huang Hua, Komar Chad A., Bailer Peter F., Parker Jared B., Blobel Gerd A., Kohli Rahul M., Wherry E. John*, Berger Shelley,*, and Shi Junwei*. Peptide-assisted genome editing permits efficient CRISPR engineering of primary T cells.
Project description:Maddalena et al. showed that the limited DNA transfer capacity (~4.7kb) of adeno associated viral (AAV) vectors can be expanded up to 14kb with triple AAV vectors for the efficient expression of the therapeutic CDH23 (10.1kb) and ALMS1 (12.5kb) genes.
Project description:Adeno-associated viral (AAV) vectors are widely used for gene therapy, providing treatment for diseases caused by absent or defective genes. Despite the success of gene therapy, AAV-manufacturing is still challenging, with production yields being limited. With increased patient demand, improvements in host cell productivity through various engineering strategies will be necessary. Here, we study the host cell proteome of AAV5 producing HEK293 cells using reversed phase nano liquid chromatography and tandem mass spectrometry (LC-MS/MS). Rela-tive label-free quantitation (LFQ) was performed allowing a comparison of transfected vs. un-transfected cells. Gene ontology enrichment and pathway analysis revealed differential expres-sion of proteins involved in fundamental cellular processes such as metabolism, proliferation and cell death. Furthermore, changes in expression of proteins involved in endocytosis and lysosomal degradation were observed. Our data provides highly valuable insights into cellular mechanisms involved during recombinant AAV production by HEK293 cells thus potentially enabling further improvements of gene therapy product manufacturing.