| 1. |
- Aldskogius, Håkan, 1943-, et al.
(författare)
-
Regulation of boundary cap neural crest stem cell differentiation after transplantation
- 2009
-
Ingår i: Stem Cells. - : Oxford University Press (OUP). - 1066-5099 .- 1549-4918. ; 27:7, s. 1592-1603
-
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.
|
|
| 2. |
|
|
| 3. |
- Hjerling-Leffler, Jens
(författare)
-
Sensory neurons : stem cells and development
- 2006
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The sensory nervous system is the only means we have of communicating with the surrounding world. The neurons responsible for the sensation of pain, touch, the ability to know the position of our limbs and part of maintenance of body posture are located in the dorsal root ganglia (DRG). Stem cell biology has, during the recent years greatly enhanced our understanding of developmental processes. The aim of this thesis was to isolate and characterize stem cells from the sensory nervous system and to study the development of functional neuronal subtypes. In the work presented 1 show the identification of a neural crest stem cell (NCSC) that is located in the boundary cap (BC). The BC is a transient structure present during embryogenesis lining the boundary between the peripheral and central nervous system at the exit/entry zone of sensory and motor efferents. This multipotent stem cell is unique as compared to previously described NCSCs, in its ability to form sensory neurons in vitro. The sensory neurons are functionally active as assayed by calcium imaging using temperature stimuli and sensory specific transient receptor potential (TRP)-channel ligands. I further show that the boundary cap neural crest stem cell (bNCSC) can give rise to Schwann cells that myclinate regenerating axons in vivo, suggesting a possibility for the use of these stem cells for regenerative therapy. The bNCSC express the well described stem cell marker, stage specific antigen 1 (SSEA-1) as well as proteins involved in the production of gamma amino butyric acid (GABA). Furthermore, GABA drastically reduces the proliferation of bNCSC, in a pathway independent of intracellular signalling. Antagonizing endogenous production using GABAA receptor antagonist bicuculline increases the same. This suggests GABA as a signal to regulate proliferation in the BC stem cell niche and thus providing the basis for a possible increase of production in response to an injury. In the last part of the thesis 1 describe and define the developmental emergence of different subtypes of developing sensory neurons based on functional responses to capsaicin, menthol, and cinnamon aldehyde, agonists to TRPV1, TRPM8 and TRPA 1 respectively.
|
|
| 4. |
- Hjerling-Leffler, Jens, et al.
(författare)
-
The boundary cap: a source of neural crest stem cells that generate multiple sensory neuron subtypes.
- 2005
-
Ingår i: Development (Cambridge, England). - : The Company of Biologists. - 0950-1991 .- 1477-9129. ; 132:11, s. 2623-32
-
Tidskriftsartikel (refereegranskat)abstract
- The boundary cap (BC) is a transient neural crest-derived group of cells located at the dorsal root entry zone (DREZ) that have been shown to differentiate into sensory neurons and glia in vivo. We find that when placed in culture, BC cells self-renew, show multipotency in clonal cultures and express neural crest stem cell (NCSCs) markers. Unlike sciatic nerve NCSCs, the BC-NCSC (bNCSCs) generates sensory neurons upon differentiation. The bNCSCs constitute a common source of cells for functionally diverse types of neurons, as a single bNCSC can give rise to several types of nociceptive and thermoreceptive sensory neurons. Our data suggests that BC cells comprise a source of multipotent sensory specified stem cells that persist throughout embryogenesis.
|
|
| 5. |
- hower, lee, et al.
(författare)
-
investigating cell type changes in schizophrenia with spatially-resolved transcriptomics
-
Annan publikation (populärvet., debatt m.m.)abstract
- Schizophrenia is a heritable and genetically complex disorder with poorly understood aetiology. Previous study from our lab has shown that this disorder could affect a limited number of cell types in the brain1. Here, we build on these findings and present the first spatially-resolved transcriptomics study of schizophrenia with a large number of samples (17 in total). By comparing spatial cell type distributions in diseased and healthy prefrontal cortices, we discover that certain non-neuronal cell types change their co-localization patterns
|
|
| 6. |
- Lundin, Elin, 1983-, et al.
(författare)
-
Spatiotemporal mapping of RNA editing in the developing mouse brain using in situ sequencing reveals regional and cell-type-specific regulation
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Background: Adenosine-to-inosine (A-to-I) RNA editing is a process that contributes to the diversification of proteins that has been shown to be essential for neurotransmission and other neuronal functions. However, the spatiotemporal and diversification properties of RNA editing in the brain are largely unknown. Here, we applied in situ sequencing to distinguish between edited and unedited transcripts in distinct regions of the mouse brain at four developmental stages, and investigate the diversity of the RNA landscape.Results: We analyzed RNA editing at codon-altering sites using in situ sequencing at single-cell resolution, in combination with the detection of individual ADAR enzymes and specific cell type marker transcripts. This approach revealed cell-type specific regulation of RNA editing of a set of transcripts, and developmental and regional variation in editing levels for many of the targeted sites. We found increasing editing diversity throughout development, which arises through regional- and cell type-specific regulation of ADAR enzymes and target transcripts.Conclusions: Our single-cell in situ sequencing method has proved useful to study the complex landscape of RNA editing and our results indicate that this complexity arises due to distinct mechanisms of regulating individual RNA editing sites, acting both regionally and in specific cell types.
|
|
| 7. |
- Lundin, Elin, et al.
(författare)
-
Spatiotemporal mapping of RNA editing in the developing mouse brain using in situ sequencing reveals regional and cell-type-specific regulation
- 2020
-
Ingår i: BMC Biology. - : Springer Science and Business Media LLC. - 1741-7007. ; 18:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background Adenosine-to-inosine (A-to-I) RNA editing is a process that contributes to the diversification of proteins that has been shown to be essential for neurotransmission and other neuronal functions. However, the spatiotemporal and diversification properties of RNA editing in the brain are largely unknown. Here, we applied in situ sequencing to distinguish between edited and unedited transcripts in distinct regions of the mouse brain at four developmental stages, and investigate the diversity of the RNA landscape. Results We analyzed RNA editing at codon-altering sites using in situ sequencing at single-cell resolution, in combination with the detection of individual ADAR enzymes and specific cell type marker transcripts. This approach revealed cell-type-specific regulation of RNA editing of a set of transcripts, and developmental and regional variation in editing levels for many of the targeted sites. We found increasing editing diversity throughout development, which arises through regional- and cell type-specific regulation of ADAR enzymes and target transcripts. Conclusions Our single-cell in situ sequencing method has proved useful to study the complex landscape of RNA editing and our results indicate that this complexity arises due to distinct mechanisms of regulating individual RNA editing sites, acting both regionally and in specific cell types.
|
|
| 8. |
- Marques, Sueli, et al.
(författare)
-
Transcriptional Convergence of Oligodendrocyte Lineage Progenitors during Development
- 2018
-
Ingår i: Developmental Cell. - : Elsevier BV. - 1878-1551 .- 1534-5807. ; 46:4, s. 504-517
-
Tidskriftsartikel (refereegranskat)abstract
- Pdgfra+ oligodendrocyte precursor cells (OPCs) arise in distinct specification waves during embryogenesis in the central nervous system (CNS). It is unclear whether there is a correlation between these waves and different oligodendrocyte (OL) states at adult stages. Here, we present bulk and single-cell transcriptomics resources providing insights on how transitions between these states occur. We found that post-natal OPCs from brain and spinal cord present similar transcriptional signatures. Moreover, post-natal OPC progeny of E13.5 Pdgfra+ cells present electrophysiological and transcriptional profiles similar to OPCs derived from subsequent specification waves, indicating that Pdgfra+ pre-OPCs rewire their transcriptional network during development. Single-cell RNA-seq and lineage tracing indicates that a subset of E13.5 Pdgfra+ cells originates cells of the pericyte lineage. Thus, our results indicate that embryonic Pdgfra+ cells in the CNS give rise to distinct post-natal cell lineages, including OPCs with convergent transcriptional profiles in different CNS regions.
|
|
| 9. |
- Qian, Xiaoyan, et al.
(författare)
-
Probabilistic cell typing enables fine mapping of closely related cell types in situ
- 2020
-
Ingår i: Nature Methods. - : Springer Science and Business Media LLC. - 1548-7091 .- 1548-7105. ; 17:1, s. 101-106
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding the function of a tissue requires knowing the spatial organization of its constituent cell types. In the cerebral cortex, single-cell RNA sequencing (scRNA-seq) has revealed the genome-wide expression patterns that define its many, closely related neuronal types, but cannot reveal their spatial arrangement. Here we introduce probabilistic cell typing by in situ sequencing (pciSeq), an approach that leverages prior scRNA-seq classification to identify cell types using multiplexed in situ RNA detection. We applied this method by mapping the inhibitory neurons of mouse hippocampal area CA1, for which ground truth is available from extensive prior work identifying their laminar organization. Our method identified these neuronal classes in a spatial arrangement matching ground truth, and further identified multiple classes of isocortical pyramidal cell in a pattern matching their known organization. This method will allow identifying the spatial organization of closely related cell types across the brain and other tissues.
|
|
| 10. |
- Ribeiro, Diogo, et al.
(författare)
-
Efficient expansion and dopaminergic differentiation of human fetal ventral midbrain neural stem cells by midbrain morphogens
- 2013
-
Ingår i: Neurobiology of Disease. - : Elsevier BV. - 0969-9961 .- 1095-953X. ; 49, s. 118-127
-
Tidskriftsartikel (refereegranskat)abstract
- Human fetal midbrain tissue grafting has provided proof-of-concept for dopamine cell replacement therapy (CRT) in Parkinson's disease (PD). However, limited tissue availability has hindered the development and widespread use of this experimental therapy. Here we present a method for generating large numbers of midbrain dopaminergic (DA) neurons based on expanding and differentiating neural stem/progenitor cells present in the human ventral midbrain (hVM) tissue. Our results show that hVM neurospheres (hVMN) with low cell numbers, unlike their rodent counterparts, expand the total number of cells 3-fold, whilst retaining their capacity to differentiate into midbrain DA neurons. Moreover, Wnt5a promoted DA differentiation of expanded cells resulting in improved morphological maturation, midbrain DA marker expression, DA release and electrophysiological properties. This method results in cell preparations that, after expansion and differentiation, can contain 6-fold more midbrain DA neurons than the starting VM preparation. Thus, our results provide evidence that by improving expansion and differentiation of progenitors present in the hVM it is possible to greatly enrich cell preparations for DA neurons. This method could substantially reduce the amount of human fetal midbrain tissue necessary for CRT in patients with PD, which could have major implications for the widespread adoption of this approach. (C) 2012 Elsevier Inc. All rights reserved.
|
|
| 11. |
- Zeisel, Amit, et al.
(författare)
-
Cell types in the mouse cortex and hippocampus revealed by single-cell RNA-seq
- 2015
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 347:6226, s. 1138-1142
-
Tidskriftsartikel (refereegranskat)abstract
- The mammalian cerebral cortex supports cognitive functions such as sensorimotor integration, memory, and social behaviors. Normal brain function relies on a diverse set of differentiated cell types, including neurons, glia, and vasculature. Here, we have used large-scale single-cell RNA sequencing (RNA-seq) to classify cells in the mouse somatosensory cortex and hippocampal CA1 region. We found 47 molecularly distinct subclasses, comprising all known major cell types in the cortex. We identified numerous marker genes, which allowed alignment with known cell types, morphology, and location. We found a layer I interneuron expressing Pax6 and a distinct postmitotic oligodendrocyte subclass marked by Itpr2. Across the diversity of cortical cell types, transcription factors formed a complex, layered regulatory code, suggesting a mechanism for the maintenance of adult cell type identity.
|
|
| 12. |
- Zhu, Shun-Wei, et al.
(författare)
-
Influence of environmental manipulation on exploratory behaviour in male BDNF knockout mice
- 2009
-
Ingår i: Behavioural Brain Research. - : Elsevier BV. - 0166-4328 .- 1872-7549. ; 197:2, s. 339-346
-
Tidskriftsartikel (refereegranskat)abstract
- It is widely accepted that brain derived neurotrophic factor (BDNF) plays a crucial role in mediating changes in learning and memory performance induced by environmental conditions. In order to ascertain whether BDNF modulates environmentally induced changes in exploratory behaviour, we examined mice carrying a deletion in one copy of the BDNF gene. Young heterozygous male BDNF knockout mice (BDNF+/−) and their wild-type (WT) controls were exposed to the enriched environment condition (EC) or the standard condition (SC) for 8 weeks. Exploratory behaviour was assessed in the open-field (OF) and hole-board (HB) test. Brains from EC and SC reared animals were processed for Golgi-Cox staining and the dendritic spine density in the dentate gyrus (DG) and CA1 hippocampal regions were examined. We found behavioural differences both due to the genetic modification and the environmental manipulation, with the BDNF+/− mice being more active in the OF whereas the EC mice had increased exploratory behaviour in the HB test. Environmental enrichment also led to an increase in dendritic spines in the hippocampal CA1 region and DG of the wild-type mice. This effect was also found in the enriched BDNF+/− mice, but was less pronounced. Our findings support the critical role of BDNF in behavioural and neural plasticity associated with environmental enrichment and suggest that besides maze learning performance, BDNF dependent mechanisms are also involved in other aspects of behaviour. Here we provide additional evidence that exploratory activity is influenced by BDNF.
|
|
