Browsing by Author "Porteus, Matthew H."
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Item Gene correction for SCID-X1 in long-term hematopoietic stem cells(Springer Nature, 2019) Pavel-Dinu, Mara; Wiebking, Volker; Dejene, Beruh T.; Srifa, Waracharee; Mantri, Sruthi; Nicolas, Carmencita E.; Lee, Ciaran; Bao, Gang; Kildebeck, Eric J.; Punjya, Niraj; Sindhu, Camille; Inlay, Matthew A.; Saxena, Nivedita; DeRavin, Suk See; Malech, Harry; Roncarolo, Maria Grazia; Weinberg, Kenneth I.; Porteus, Matthew H.Gene correction in human long-term hematopoietic stem cells (LT-HSCs) could be an effective therapy for monogenic diseases of the blood and immune system. Here we describe an approach for X-linked sSevere cCombined iImmunodeficiency (SCID-X1) using targeted integration of a cDNA into the endogenous start codon to functionally correct disease-causing mutations throughout the gene. Using a CRISPR-Cas9/AAV6 based strategy, we achieve up to 20% targeted integration frequencies in LT-HSCs. As measures of the lack of toxicity we observe no evidence of abnormal hematopoiesis following transplantation and no evidence of off-target mutations using a high-fidelity Cas9 as a ribonucleoprotein complex. We achieve high levels of targeting frequencies (median 45%) in CD34+ HSPCs from six SCID-X1 patients and demonstrate rescue of lymphopoietic defect in a patient derived HSPC population in vitro and in vivo. In sum, our study provides specificity, toxicity and efficacy data supportive of clinical development of genome editing to treat SCID-Xl.Item Genome editing of donor-derived T-cells to generate allogenic chimeric antigen receptor-modified T cells: Optimizing αβ T cell-depleted haploidentical hematopoietic stem cell transplantation(Ferrata-Storti Foundation, 2021) Wiebking, Volker; Lee, Ciaran M.; Mostrel, Nathalie; Lahiri, Premanjali; Bak, Rasmus; Bao, Gang; Roncarolo, Maria Grazia; Bertaina, Alice; Porteus, Matthew H.Allogeneic hematopoietic stem cell transplantation is an effective therapy for high-risk leukemias. In children, graft manipulation based on the selective removal of αβ T cells and B cells has been shown to reduce the risk of acute and chronic graft-versus-host disease, thus allowing the use of haploidentical donors which expands the population that allogeneic hematopoietic stem cell transplantation can be used in. Leukemic relapse, however, remains a problem. T cells expressing chimeric antigen receptors can potently eliminate leukemia, including in the central nervous system. We hypothesized that by modifying donor αβ T cells to simultaneously express a CD19-specific chimeric antigen receptors and inactivating the T cell receptor by genome editing, we could create a therapy that enhances the anti-leukemic efficacy of the stem cell transplant without increasing the risk of graft-versus-host disease. Using genome editing with Cas9 ribonucleoprotein and adeno-associated virus serotype 6, we integrate a CD19-specific chimeric antigen receptor in-frame into the TRAC locus. Greater than 90% of cells lost TCR expression, while >75% expressed the CAR. The product was further purified to ultimately have less than 0.05% residual TCR+ cells. In vitro, the CAR T cells efficiently eliminated target cells and produced high cytokine levels when challenged with CD19+ leukemia cells. In vivo, the gene modified T cells eliminated leukemia without causing xenogeneic graft-versus-host disease in a xenograft model. Gene editing was highly specific with no evidence of off-target effects. These data support the concept that the addition of αβ T cell-derived, genome edited T cells expressing CD19-specific chimeric antigen receptors could enhance the anti-leukemic efficacy of αβ T cell-depleted haploidentical hematopoietic stem cell transplantation without increasing the risk of graft-versus-host disease.Item Highly efficient editing of the β-globin gene in patient-derived hematopoietic stem and progenitor cells to treat sickle cell disease(Oxford University Press, 2019) Park, So Hyun; Lee, Ciaran M.; Dever, Daniel P.; Davis, Timothy H.; Camarena, Joab; Srifa, Waracharee; Zhang, Yankai; Paikari, Alireza; Chang, Alicia K.; Porteus, Matthew H.; Sheehan, Vivien A.; Bao, GangSickle cell disease (SCD) is a monogenic disorder that affects millions worldwide. Allogeneic hematopoietic stem cell transplantation is the only available cure. Here, we demonstrate the use of CRISPR/Cas9 and a short single-stranded oligonucleotide template to correct the sickle mutation in the β-globin gene in hematopoietic stem and progenitor cells (HSPCs) from peripheral blood or bone marrow of patients with SCD, with 24.5 ± 7.6% efficiency without selection. Erythrocytes derived from gene-edited cells showed a marked reduction of sickle cells, with the level of normal hemoglobin (HbA) increased to 25.3 ± 13.9%. Gene-corrected SCD HSPCs retained the ability to engraft when transplanted into non-obese diabetic (NOD)-SCID-gamma (NSG) mice with detectable levels of gene correction 16–19 weeks post-transplantation. We show that, by using a high-fidelity SpyCas9 that maintained the same level of on-target gene modification, the off-target effects including chromosomal rearrangements were significantly reduced. Taken together, our results demonstrate efficient gene correction of the sickle mutation in both peripheral blood and bone marrow-derived SCD HSPCs, a significant reduction in sickling of red blood cells, engraftment of gene-edited SCD HSPCs in vivo and the importance of reducing off-target effects; all are essential for moving genome editing based SCD treatment into clinical practice.Item Human genome-edited hematopoietic stem cells phenotypically correct Mucopolysaccharidosis type I(Springer Nature, 2019) Gomez-Ospina, Natalia; Scharenberg, Samantha G.; Mostrel, Nathalie; Bak, Rasmus O.; Mantri, Sruthi; Quadros, Rolen M.; Gurumurthy, Channabasavaiah B.; Lee, Ciaran; Bao, Gang; Suarez, Carlos J.; Khan, Shaukat; Sawamoto, Kazuki; Tomatsu, Shunji; Raj, Nitin; Attardi, Laura D.; Aurelian, Laure; Porteus, Matthew H.Lysosomal enzyme deficiencies comprise a large group of genetic disorders that generally lack effective treatments. A potential treatment approach is to engineer the patient’s own hematopoietic system to express high levels of the deficient enzyme, thereby correcting the biochemical defect and halting disease progression. Here, we present an efficient ex vivo genome editing approach using CRISPR-Cas9 that targets the lysosomal enzyme iduronidase to the CCR5 safe harbor locus in human CD34+ hematopoietic stem and progenitor cells. The modified cells secrete supra-endogenous enzyme levels, maintain long-term repopulation and multi-lineage differentiation potential, and can improve biochemical and phenotypic abnormalities in an immunocompromised mouse model of Mucopolysaccharidosis type I. These studies provide support for the development of genome-edited CD34+ hematopoietic stem and progenitor cells as a potential treatment for Mucopolysaccharidosis type I. The safe harbor approach constitutes a flexible platform for the expression of lysosomal enzymes making it applicable to other lysosomal storage disorders.Item The TRACE-Seq method tracks recombination alleles and identifies clonal reconstitution dynamics of gene targeted human hematopoietic stem cells(Springer Nature, 2021) Sharma, Rajiv; Dever, Daniel P.; Lee, Ciaran M.; Azizi, Armon; Pan, Yidan; Camarena, Joab; Köhnke, Thomas; Bao, Gang; Porteus, Matthew H.; Majeti, RavindraTargeted DNA correction of disease-causing mutations in hematopoietic stem and progenitor cells (HSPCs) may enable the treatment of genetic diseases of the blood and immune system. It is now possible to correct mutations at high frequencies in HSPCs by combining CRISPR/Cas9 with homologous DNA donors. Because of the precision of gene correction, these approaches preclude clonal tracking of gene-targeted HSPCs. Here, we describe Tracking Recombination Alleles in Clonal Engraftment using sequencing (TRACE-Seq), a methodology that utilizes barcoded AAV6 donor template libraries, carrying in-frame silent mutations or semi-randomized nucleotides outside the coding region, to track the in vivo lineage contribution of gene-targeted HSPC clones. By targeting the HBB gene with an AAV6 donor template library consisting of ~20,000 possible unique exon 1 in-frame silent mutations, we track the hematopoietic reconstitution of HBB targeted myeloid-skewed, lymphoid-skewed, and balanced multi-lineage repopulating human HSPC clones in mice. We anticipate this methodology could potentially be used for HSPC clonal tracking of Cas9 RNP and AAV6-mediated gene targeting outcomes in translational and basic research settings.