Project description:The use of induced pluripotent stem cells (iPSCs) is an exciting frontier in the study and treatment of human diseases through the generation of specific cell types. Here we show the derivation of iPSCs from human non-mobilized peripheral blood (PB) and bone marrow (BM) mononuclear cells (MNCs) by retroviral transduction of OCT3/4, SOX2, KLF4 and c-MYC. The PB- and BM-derived iPSCs were indistinguishable from human embryonic stem cells (hESCs) with respect to morphology, expression of surface antigens and pluripotency-associated transcription factors, global gene expression profiles and differentiation potential in vitro and in vivo. Infected PB and BM MNCs gave rise to iPSCs in the presence of several cytokines, although transduction efficiencies were not high. We found that 5×105 PB MNCs, which corresponds to less than 1 ml of PB, was enough for the generation of several iPSC colonies. Generation of iPSCs from MNCs of non-mobilized PB, with its relative efficiency and ease of harvesting, could enable the therapeutic use of patient-specific pluripotent stem cells.
Project description:Induced pluripotent stem cell (iPSC) technology allows for the generation of patient-specific pluripotent stem cells, from somatic cell sources, thereby providing a novel cell therapy platform for severe degenerative diseases. One of the key issues for clinical-grade iPSC derivation is the accessibility of donor cells used for reprogramming and subsequent feasiblity of reprogramming into a pluripotent state. We used microarrays to detail the global gene expression profiles from blood cells. The use of blood cells allows for minimally invasive tissue procurement under GMP conditions and rapid cellular reprogramming, mobilized HPCs and unmobilized PBMCs would be ideal somatic cell sources for clinical-grade iPSC derivation. We examined the feasibility of reprogramming mobilized GMP-grade hematopoietic progenitor cells (HPCs) and mononuclear myeloid cells and tested the pluripotency of derived iPS clones.
Project description:Induced pluripotent stem cell (iPSC) technology allows for the generation of patient-specific pluripotent stem cells, from somatic cell sources, thereby providing a novel cell therapy platform for severe degenerative diseases. One of the key issues for clinical-grade iPSC derivation is the accessibility of donor cells used for reprogramming and subsequent feasiblity of reprogramming into a pluripotent state. We used microarrays to detail the global gene expression profiles from blood cells. The use of blood cells allows for minimally invasive tissue procurement under GMP conditions and rapid cellular reprogramming, mobilized HPCs and unmobilized PBMCs would be ideal somatic cell sources for clinical-grade iPSC derivation.
Project description:A variety of somatic cells can be reprogrammed to induced pluripotent stem cells (iPSCs), but the small number of CD34+ hematopoietic stem cells (HSCs) present in non-mobilized peripheral blood (PB) would be a convenient and desirable starting target. We report here a simple method for targeting derivation of iPSC from non-mobilized PB CD34+ HSCs using immunobead purification and 2-4 day culture to achieve enrichment of CD34+ HSCs to 80±9%, followed by reprogramming transduction with loxP-flanked polycistronic (Oct4, Klf4, Sox2, and c-Myc) STEMCCA-loxP lentivector at an MOI of 2. Our yield was 4.7±2.2 iPSC colonies (n=12) per 20 mL non-mobilized peripheral blood, where most colonies had single copy STEMCCA-loxP that was easily excised by transient transfection expression of Cre. Resultant iPSC clones expressed pluripotent cell markers, had genomic methylation pattern closely matching embryonic stem cells, and generated teratomas containing tissues of all three germ lineages in immunodeficient mice. Furthermore, we conclude that these iPSC are derived from the non-mobilized CD34+ HSCs enriched from PB rather than from any lymphocyte or monocyte contaminants because they lacked somatic rearrangements typical of T or B lymphocytes, and because we demonstrated that purified CD14+ monocytes do not yield iPSC colonies under these reprogramming conditions.