| 1. |
- Moody, Jennifer, et al.
(author)
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Endoglin is not critical for hematopoietic stem cell engraftment and reconstitution but regulates adult erythroid development
- 2007
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In: Stem Cells. - : Oxford University Press (OUP). - 1549-4918 .- 1066-5099. ; 25:11, s. 2809-2819
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Journal article (peer-reviewed)abstract
- Endoglin is a transforming growth factor-beta (TGF-beta) accessory receptor recently identified as being highly expressed on long-term repopulating hematopoietic stem cells (HSC) However, little is known regarding its function in these cells. We have used two complementary approaches toward understanding endoglin's role in HSC biology: one that efficiently knocks down expression via lentiviral-driven short hairpin RNA and another that uses retroviral-mediated overexpression. Altering endoglin expression had functional consequences for hematopoietic progenitors in vitro such that endoglin-suppressed myeloid progenitors (colony-forming unit-granulocyte macrophage) displayed a higher degree of sensitivity to TGF-beta-mediated growth inhibition, whereas endoglin-overexpressing cells were partially resistant. However, transplantation of transduced bone marrow enriched in primitive hematopoietic stem and progenitor cells revealed that neither endoglin suppression nor endoglin overexpression affected the ability of stem cells to short-term or long-term repopulate recipient marrow. Furthermore, transplantation of cells altered in endoglin expression yielded normal white blood cell proportions and peripheral blood platelets. Interestingly, decreasing endoglin expression increased the clonogenic capacity of early blast-forming unit-erythroid progenitors, whereas overexpression compromised erythroid differentiation at the basophilic erythroblast phase, suggesting a pivotal role for endoglin at key stages of adult erythropoietic development.
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| 2. |
- Wahlestedt, Martin, et al.
(author)
-
Somatic Cells with a Heavy Mitochondrial DNA Mutational Load Render Induced Pluripotent Stem Cells with Distinct Differentiation Defects
- 2014
-
In: Stem Cells. - : Oxford University Press (OUP). - 1066-5099 .- 1549-4918. ; 32:5, s. 1173-1182
-
Journal article (peer-reviewed)abstract
- It has become increasingly clear that several age-associated pathologies associate with mutations in the mitochondrial genome. Experimental modeling of such events has revealed that acquisition of mitochondrial DNA (mtDNA) damage can impair respiratory function and, as a consequence, can lead to widespread decline in cellular function. This includes premature aging syndromes. By taking advantage of a mutator mouse model with an error-prone mtDNA polymerase, we here investigated the impact of an established mtDNA mutational load with regards to the generation, maintenance, and differentiation of induced pluripotent stem (iPS) cells. We demonstrate that somatic cells with a heavy mtDNA mutation burden were amenable for reprogramming into iPS cells. However, mutator iPS cells displayed delayed proliferation kinetics and harbored extensive differentiation defects. While mutator iPS cells had normal ATP levels and glycolytic activity, the induction of differentiation coincided with drastic decreases in ATP production and a hyperactive glycolysis. These data demonstrate the differential requirements of mitochondrial integrity for pluripotent stem cell self-renewal versus differentiation and highlight the relevance of assessing the mitochondrial genome when aiming to generate iPS cells with robust differentiation potential. Stem Cells 2014;32:1173-1182
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| 3. |
- Wahlestedt, Martin, et al.
(author)
-
Somatic cells with a heavy mitochondrial DNA mutational load render iPS cells with distinct differentiation defects.
- 2014
-
In: Stem Cells. - : Oxford University Press (OUP). - 1549-4918 .- 1066-5099. ; 32:5, s. 1173-1182
-
Journal article (peer-reviewed)abstract
- It has become increasingly clear that several age-associated pathologies associate with mutations in the mitochondrial genome. Experimental modeling of such events has revealed that acquisition of mitochondrial DNA (mtDNA) damage can impair respiratory function and, as a consequence, can lead to widespread decline in cellular function. This includes premature aging syndromes. By taking advantage of a mutator mouse model with an error-prone mtDNA polymerase, we here investigated the impact of an established mtDNA mutational load with regards to the generation, maintenance and differentiation of induced pluripotent stem (iPS) cells. We demonstrate that somatic cells with a heavy mtDNA mutation burden were amenable for reprogramming into iPS cells. However, mutator iPS cells displayed delayed proliferation kinetics and harbored extensive differentiation defects. While mutator iPS cells had normal ATP levels and glycolytic activity, the induction of differentiation coincided with drastic decreases in ATP production and a hyperactive glycolysis. These data demonstrate the differential requirements of mitochondrial integrity for pluripotent stem cell self-renewal versus differentiation, and highlight the relevance of assessing the mitochondrial genome when aiming to generate iPS cells with robust differentiation potential. Stem Cells 2014.
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