The goal of Project 2 is correction of the sickle cell disease (SCD) and B-thalassemia (B-thal) mutations, using patient derived somafic cells and their induced pluripotent stem (iPS) cell derivatives. These cells will ultimately be converted to hematopoietic stem cells (HSCs) to reconstitute patient hematopoietic systems. As an alternative to conventional cDNA-based genetic therapies, IPS cells or their somafic precursors, will be modified by a sequence-specific gene targeting strategy, small fragment homologous replacement (SFHR), triplex forming oligonucleotide (TFO)-mediated homologous exchange and by classical homologous recombination (HR). These studies will be carried out in the presence and absence of zinc finger nucleases (ZFNs) and meganucleases and meganucleases (MNs) potent stimulators of recombination. Previous studies from our lab have shown that oligo/polynucleotide small DNA fragments (SDFs) carrying the A>T sickle mutation (B[S]-DFs), when microinjected into wild-type human hematopoietic stem cells (HSCs), will convert the endogenous wild-type globin (B[A]-globin) into the sickle cell disease B[S]-globin at frequencies of at least 7%. This project will test several hypotheses in 2 Specific Aims.
Aim 1 will test the hypotheses that SDF-modified and TFO-modified human SCD and B-thal somafic cells and their IPS cell derivatives can be converted to clonal isoaltes IPS cells that are viable, karyotypically stable, and can be differentiated into engraftable hematopoietic precursors.
Aim 2 : will test the hyopthesis that classical HR is a reliable alterative method for correcting specific genomic mutations in the B-globin globin gene. Somatic and IPS cells homozygous for the B[S]-globin or defined B-thal mutations, will be genetically corrected by SDF, TFO, and classical HR mediated homologous exchange, to generate clonal populations of B-globin heterozygote IPS cells. If patient somafic cells are used for correction, they will be converted to IPS cells when a clonal population has been isolated. The cells will be transfected with SDFs by electroporation or microinjection and in the presence and absence of ZFNs or sequence-specific MNs.
Each Aim will evaluate the corrected cells in terms of their karyotypic stability, genetic integrity, the ability to generate or maintain IPS cell phenotype, and the ability to differentiate in vitro into HSC. Teratoma formation will be evaluated by Core C and gene expression patterns after correction will also be evaluated in through Core B ad the UCSF Array Core. While initial studies will be carried out using retrovirally reprogrammed IPS cells, as new patient-specific IPS cell lines become available through Project 1 and Core B, they will be corrected and evaluated. Finally, corrected IPS cells generated in Project 2 will be evaluated in Project 3 for their ability to differentiate into hematopoietic precursors that will engraft into NOD-SCID mice for hematopoietic reconstitution.
This project will develop protocols for correcting disease-causing mutations in sickle cell disease (SCD) and B-thalassemia (B-thal) patient-specific somafic and induced pluripotent stem (IPS) cells. Autologous, corrected iPS cells that can be differentiated into hematopoietic stem cells (HSC) will be a critical component of a comprehensive cell and gene therapy for these diseases. The impact of developing these protocols to generate autologous, SCD and B-thal corrected HSC from corrected patient IPS cells will be significant since these hemoglobinopathies are among the most prevalent inherited diseases worldwide.
|Suzuki, Shingo; Sargent, R Geoffrey; Illek, Beate et al. (2016) TALENs Facilitate Single-step Seamless SDF Correction of F508del CFTR in Airway Epithelial Submucosal Gland Cell-derived CF-iPSCs. Mol Ther Nucleic Acids 5:e273|
|Beyer, Ashley I; Muench, Marcus O (2016) Comparison of human hematopoietic reconstitution in different strains of immunodeficient mice. Stem Cells Dev :|
|Ye, Lin; Wang, Jiaming; Tan, Yuting et al. (2016) Genome editing using CRISPR-Cas9 to create the HPFH genotype in HSPCs: An approach for treating sickle cell disease and Î²-thalassemia. Proc Natl Acad Sci U S A 113:10661-5|
|Baimukanova, Gyulnar; Miyazawa, Byron; Potter, Daniel R et al. (2016) Platelets regulate vascular endothelial stability: assessing the storage lesion and donor variability of apheresis platelets. Transfusion 56 Suppl 1:S65-75|
|Wiemels, J L; de Smith, A J; Xiao, J et al. (2016) A functional polymorphism in the CEBPE gene promoter influences acute lymphoblastic leukemia risk through interaction with the hematopoietic transcription factor Ikaros. Leukemia 30:1194-7|
|Mahajan, Maya M; Cheng, Betty; Beyer, Ashley I et al. (2015) A quantitative assessment of the content of hematopoietic stem cells in mouse and human endosteal-bone marrow: a simple and rapid method for the isolation of mouse central bone marrow. BMC Hematol 15:9|
|Muench, Marcus O; Beyer, Ashley I; Fomin, Marina E et al. (2014) The adult livers of immunodeficient mice support human hematopoiesis: evidence for a hepatic mast cell population that develops early in human ontogeny. PLoS One 9:e97312|
|Xie, Fei; Ye, Lin; Chang, Judy C et al. (2014) Seamless gene correction of Î²-thalassemia mutations in patient-specific iPSCs using CRISPR/Cas9 and piggyBac. Genome Res 24:1526-33|
|Ye, Lin; Wang, Jiaming; Beyer, Ashley I et al. (2014) Seamless modification of wild-type induced pluripotent stem cells to the natural CCR5Î”32 mutation confers resistance to HIV infection. Proc Natl Acad Sci U S A 111:9591-6|
|Fomin, M E; Togarrati, P P; Muench, M O (2014) Progress and challenges in the development of a cell-based therapy for hemophilia A. J Thromb Haemost 12:1954-65|
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