Ontology highlight
ABSTRACT:
PROVIDER: PRJNA795336 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Homology Directed Repair (HDR) enables precise genome editing and holds great promise in the gene therapy field. However, the implementation of HDR-based therapies is hindered by limited efficiency in comparison to methods that exploit alternative DNA repair routes, such as Non-Homologous End Joining (NHEJ). In this study, we demonstrate the development of a functional, pooled screening platform utilizing an HDR-based readout to identify protein-based reagents that improve HDR outcomes in human hematopoietic stem and progenitor cells (HSPCs), a clinically relevant cell type for gene therapy. We leveraged this screening platform to explore sequence diversity at the binding interface of the NHEJ inhibitor i53 and its target, 53BP1, and we identified optimized i53 variants that enable new intermolecular bonds and robustly increase HDR. These variants specifically reduce insertion-deletion outcomes and also synergize with a DNAPK inhibitor to increase HDR rates. When applied at manufacturing scale, the incorporation of improved variants results in a significant increase in cells with at least one repaired allele and improved HDR in long-term HSPCs subpopulations, while not increasing off-target editing or gross chromosomal rearrangements. We anticipate the pooled screening platform will enable discovery of future gene editing reagents that improve HDR outcomes, such as the i53 variants reported here.
2024-02-11 | GSE242777 | GEO
Project description:Homology Directed Repair (HDR) enables precise genome editing and holds great promise in the gene therapy field. However, the implementation of HDR-based therapies is hindered by limited efficiency in comparison to methods that exploit alternative DNA repair routes, such as Non-Homologous End Joining (NHEJ). In this study, we demonstrate the development of a functional, pooled screening platform utilizing an HDR-based readout to identify protein-based reagents that improve HDR outcomes in human hematopoietic stem and progenitor cells (HSPCs), a clinically relevant cell type for gene therapy. We leveraged this screening platform to explore sequence diversity at the binding interface of the NHEJ inhibitor i53 and its target, 53BP1, and we identified optimized i53 variants that enable new intermolecular bonds and robustly increase HDR. These variants specifically reduce insertion-deletion outcomes and also synergize with a DNAPK inhibitor to increase HDR rates. When applied at manufacturing scale, the incorporation of improved variants results in a significant increase in cells with at least one repaired allele and improved HDR in long-term HSPCs subpopulations, while not increasing off-target editing or gross chromosomal rearrangements. We anticipate the pooled screening platform will enable discovery of future gene editing reagents that improve HDR outcomes, such as the i53 variants reported here.
2024-02-11 | GSE242748 | GEO
Project description:Homology Directed Repair (HDR) enables precise genome editing and holds great promise in the gene therapy field. However, the implementation of HDR-based therapies is hindered by limited efficiency in comparison to methods that exploit alternative DNA repair routes, such as Non-Homologous End Joining (NHEJ). In this study, we demonstrate the development of a functional, pooled screening platform utilizing an HDR-based readout to identify protein-based reagents that improve HDR outcomes in human hematopoietic stem and progenitor cells (HSPCs), a clinically relevant cell type for gene therapy. We leveraged this screening platform to explore sequence diversity at the binding interface of the NHEJ inhibitor i53 and its target, 53BP1, and we identified optimized i53 variants that enable new intermolecular bonds and robustly increase HDR. These variants specifically reduce insertion-deletion outcomes and also synergize with a DNAPK inhibitor to increase HDR rates. When applied at manufacturing scale, the incorporation of improved variants results in a significant increase in cells with at least one repaired allele and improved HDR in long-term HSPCs subpopulations, while not increasing off-target editing or gross chromosomal rearrangements. We anticipate the pooled screening platform will enable discovery of future gene editing reagents that improve HDR outcomes, such as the i53 variants reported here.
2024-02-11 | GSE242749 | GEO
Project description:Homology Directed Repair (HDR) enables precise genome editing and holds great promise in the gene therapy field. However, the implementation of HDR-based therapies is hindered by limited efficiency in comparison to methods that exploit alternative DNA repair routes, such as Non-Homologous End Joining (NHEJ). In this study, we demonstrate the development of a functional, pooled screening platform utilizing an HDR-based readout to identify protein-based reagents that improve HDR outcomes in human hematopoietic stem and progenitor cells (HSPCs), a clinically relevant cell type for gene therapy. We leveraged this screening platform to explore sequence diversity at the binding interface of the NHEJ inhibitor i53 and its target, 53BP1, and we identified optimized i53 variants that enable new intermolecular bonds and robustly increase HDR. These variants specifically reduce insertion-deletion outcomes and also synergize with a DNAPK inhibitor to increase HDR rates. When applied at manufacturing scale, the incorporation of improved variants results in a significant increase in cells with at least one repaired allele and improved HDR in long-term HSPCs subpopulations, while not increasing off-target editing or gross chromosomal rearrangements. We anticipate the pooled screening platform will enable discovery of future gene editing reagents that improve HDR outcomes, such as the i53 variants reported here.
2024-02-11 | GSE248843 | GEO
Project description:Gene disruption by CRISPR/Cas9 is highly efficient and relies on the error-prone non-homologous end-joining (NHEJ) pathway. Conversely, precise gene editing requires homology-directed repair (HDR), which occurs at a lower frequency than NHEJ in mammalian cells. Here, by testing whether manipulation of DNA repair factors would improve HDR efficacy, we show that transient ectopic co-expression of RAD52 and a dominant-negative 53BP1 (dn53BP1) synergize to enable efficient HDR using a single-stranded oligonucleotide DNA donor template at multiple loci in human cells, including patient-derived induced pluripotent stem (iPS) cells. Co-expression of RAD52 and dn53BP1 improves multiplexed HDR-mediated editing, whereas expression of RAD52 alone enhances HDR with Cas9 nickase. Our data show that the frequency of NHEJ-mediated DSB repair in the presence of these two factors is not suppressed, and suggest that dn53BP1 competitively antagonizes 53BP1 to augment HDR in combination with RAD52. Importantly, co-expression of RAD52 and dn53BP1 does not alter Cas9 off-target activity. These findings support the use of RAD52 and dn53BP1 co-expression to overcome bottlenecks that limit HDR in precision genome editing.
2017-11-23 | GSE103241 | GEO
Project description:The CRISPR system identified in Streptococcus pyogenes (Sp) has been widely applied in genome editing. In this system, under the direction of gRNA, endonuclease SpCas9 cut both strands of the cognate DNA. These processes may disrupt the open reading frame of the gene and generate a knockout (KO) allele or achieve precise gene knockin (KI). Here we report the dynamics and DNA repair profiles after the delivery of Cas9-guide RNA ribonucleoprotein (RNP) with or without the adeno-associated virus serum type 6 (AAV6) template in four cell types. We show that editing profiles have distinct differences between cell lines. We reveal AAV6-mediated HDR effectively outcompetes MMEJ-mediated longer deletions but not NHEJ-mediated indels. However, a combination of the small molecule compounds M3814 and Trichostatin A (TSA), which potently inhibits predominant NHEJ repairs, leads to an up to a 3-fold increase in HDR efficiency.
2020-12-14 | GSE155891 | GEO
Project description:We have established a technology to endorse DSB resolution via HDR with the goal of facilitating clinical transition of HDR-based editing strategies and increase safety. We have used high throughput sequencing as deposited here to assess safety of our platform
2023-08-11 | GSE225450 | GEO
Project description:We have established a technology to endorse DSB resolution via HDR with the goal of facilitating clinical transition of HDR-based editing strategies and increase safety. We have used high throughput sequencing as deposited here to assess safety of our platform
2023-08-11 | GSE225449 | GEO
Project description:Ex-vivo gene editing in T cells and hematopoietic stem/progenitor cells (HSPCs) holds promise for treating diseases by non-homologous end joining (NHEJ) gene disruption or homology-driven repair (HDR) gene correction. Gene editing encompasses delivery of nucleases by electroporation and, when aiming to HDR, of a DNA template often provided by viral vectors. Whereas HSPCs activate robust p53-dependent DNA damage response (DDR) upon editing, the responses triggered in T cells remain poorly characterized. Here, we performed comprehensive multi-omics analyses and found that electroporation is the culprit of cytotoxicity in T cells, causing death and cell cycle delay, perturbing metabolism and inducing inflammatory response. Nuclease delivery by lipid nanoparticles (LNPs) nearly abolished cell death and ameliorated cell growth, improving tolerance to the procedure and yielding higher number of edited cells compared to electroporation. Transient transcriptomic changes upon LNP treatment were mostly caused by cellular loading with exogenous cholesterol, whose potentially detrimental impact could be overcome by limiting exposure. Notably, LNP-based HSPC editing dampened p53 pathway induction and supported higher reconstitution by long-term repopulating HSPCs compared to electroporation, reaching similar editing efficiencies. Overall, LNPs may allow efficient and stealthier ex-vivo gene editing in hematopoietic cells for treatment of human diseases.
2024-01-26 | PXD037529 | Pride
Project description:Recombination Activating Genes (RAG) are tightly regulated during lymphoid differentiation and their mutations cause a spectrum of severe immunological disorders. Haematopoietic stem/progenitor cell (HSPC) transplantation is the treatment of choice but limited by donor availability and toxicity. To overcome these issues, we developed and validated gene editing (GE) strategies targeting a corrective sequence into the human RAG1 gene by homology-directed repair (HDR). Off-target and RNA-Seq analyses were performed on edited human and patient-derived HSPCs to assesse the genome integrity and the trascriptomic profile. Whereas integration into intron 1 achieved suboptimal levels of correction, in-frame insertion into exon 2 drove faithful recapitulation of physiologic hRAG1 expression and activity.
2023-12-31 | GSE244672 | GEO