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- Aldskogius, Håkan, 1943-, et al.
(författare)
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Regulation of boundary cap neural crest stem cell differentiation after transplantation
- 2009
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Ingår i: Stem Cells. - : Oxford University Press (OUP). - 1066-5099 .- 1549-4918. ; 27:7, s. 1592-1603
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Tidskriftsartikel (refereegranskat)abstract
- Success of cell replacement therapies for neurological disorders will dependlargely on the optimization of strategies to enhance viability and control thedevelopmental fate of stem cells after transplantation. Once transplanted,stem/progenitor cells display a tendency to maintain an undifferentiatedphenotype or differentiate into inappropriate cell types. Gain and loss offunction experiments have revealed key transcription factors which drivedifferentiation of immature stem/progenitor cells toward more mature stages andeventually to full differentiation. An attractive course of action to promotesurvival and direct the differentiation of transplanted stem cells to a specific cell type would therefore be to force expression of regulatory differentiationmolecules in already transplanted stem cells, using inducible gene expressionsystems which can be controlled from the outside. Here, we explore thishypothesis by employing a tetracycline gene regulating system (Tet-On) to drivethe differentiation of boundary cap neural crest stem cells (bNCSCs) toward asensory neuron fate after transplantation. We induced the expression of the keytranscription factor Runx1 in Sox10-expressing bNCSCs. Forced expression of Runx1strongly increased transplant survival in the enriched neurotrophic environmentof the dorsal root ganglion cavity, and was sufficient to guide differentiationof bNCSCs toward a nonpeptidergic nociceptive sensory neuron phenotype both invitro and in vivo after transplantation. These findings suggest that exogenousactivation of transcription factors expression after transplantation instem/progenitor cell grafts can be a constructive approach to control theirsurvival as well as their differentiation to the desired type of cell and thatthe Tet-system is a useful tool to achieve this.
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| 2. |
- Kanaykina, Nadya, et al.
(författare)
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In vitro and in vivo effects on neural crest stem celldifferentiation by conditional activation of Runx1 short isoform and its effecton neuropathic pain behavior
- 2010
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Ingår i: Upsala Journal of Medical Sciences. - : Uppsala Medical Society. - 0300-9734 .- 2000-1967. ; 115:1, s. 56-64
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Runx1, a Runt domain transcription factor, controls thedifferentiation of nociceptors that express the neurotrophin receptor Ret,regulates the expression of many ion channels and receptors, and controls thelamina-specific innervation pattern of nociceptive afferents in the spinal cord. Moreover, mice lacking Runx1 exhibit specific defects in thermal and neuropathic pain. We investigated whether conditional activation of Runx1 short isoform(Runx1a), which lacks a transcription activation domain, influencesdifferentiation of neural crest stem cells (NCSCs) in vitro and in vivo duringdevelopment and whether postnatal Runx1a activation affects the sensitivity toneuropathic pain. METHODS: We activated ectopic expression of Runx1a in cultured NCSCs using the Tet-ON gene regulatory system during the formation ofneurospheres and analyzed the proportion of neurons and glial cells originatingfrom NCSCs. In in vivo experiments we applied doxycycline (DOX) to pregnant mice (days 8-11), i.e. when NCSCs actively migrate, and examined the phenotype ofoffsprings. We also examined whether DOX-induced activation of Runx1a in adultmice affects their sensitivity to mechanical stimulation following a constrictioninjury of the sciatic nerve. RESULTS: Ectopic Runx1a expression in cultured NCSCsresulted in predominantly glial differentiation. Offsprings in which Runx1a hadbeen activated showed retarded growth and displayed megacolon, pigment defects,and dystrophic dorsal root ganglia. In the neuropathic pain model, the threshold for mechanical sensitivity was markedly increased following activation of Runx1a.CONCLUSION: These data suggest that Runx1a has a specific role in NCSCdevelopment and that modulation of Runx1a activity may reduce mechanicalhypersensitivity associated with neuropathic pain.
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