Generation of Dopamine Neurons from Rodent Fibroblasts through the Expandable Neural Precursor Cell Stage
Mi-Sun Lim1, Mi-Yoon Chang2, Sang-Mi Kim3
1From the Graduate School of Biomedical Science and Engineering, the Hanyang Biomedical Research Institute, the Departments of Microbiology.
The Journal of Biological Chemistry
|May 30, 2015
Summary
Scientists converted mouse fibroblasts into expandable neural precursor cells (iNPCs) using Wernig factors and Bcl-xL. These iNPCs could be directed to develop into midbrain dopamine neurons, showing therapeutic potential for Parkinson disease.
Area of Science:
- Cellular reprogramming
- Neuroscience
- Developmental biology
Background:
- Transcription factors Brn2, Ascl1, and Myt1L (BAM/Wernig factors) can convert fibroblasts directly into neurons.
- The direct conversion process raises questions about potential intermediary stages and scalability.
- Conversion to expandable neural precursor cells (NPCs) offers advantages for cell yield and subtype differentiation.
Purpose of the Study:
- To investigate if fibroblast conversion can yield expandable neural precursor cells (iNPCs).
- To determine the differentiation potential and regional identity of iNPCs.
- To explore the therapeutic application of iNPCs in a Parkinson disease model.
Main Methods:
- Co-expression of Wernig factors and Bcl-xL in mouse fibroblasts.
- Culture and expansion of induced NPCs (iNPCs) for over 100 passages.
- Gene expression analysis to assess NPC identity.
- Directed differentiation of iNPCs into specific neuron subtypes by overexpressing additional transcription factors (Nurr1 and Foxa2).
- Assessment of iNPC therapeutic potential in a rat model of Parkinson disease.
Main Results:
- Fibroblasts were successfully converted into highly expandable induced NPCs (iNPCs) (>100 passages).
- iNPCs expressed common NPC markers but lacked specific regional brain identity.
- iNPCs predominantly differentiated into astrocytes but could be directed to form midbrain dopamine neurons.
- Induced midbrain dopamine neurons exhibited functional presynaptic DA neuronal activity.
- Therapeutic potential of iNPCs was evaluated in Parkinson disease model rats.
Conclusions:
- Co-expression of Wernig factors and Bcl-xL provides a method for generating expandable induced NPCs from fibroblasts.
- Induced NPCs possess a plastic differentiation potential that can be manipulated for specific neuronal subtypes.
- These findings highlight the potential of iNPCs for regenerative medicine, particularly in treating neurodegenerative diseases like Parkinson disease.
