Image Credit: Courtesy of Center for iPS Cell Research and Application
Scientific Frontline: Extended "At a Glance" Summary: Nanofiber-Based Human MPS Platform
The Core Concept: A human cell-based Microphysiological System (MPS) platform that uses induced pluripotent stem (iPS) cells and engineered nanofibers to model and quantitatively analyze the early stages of oligodendrocyte ensheathment (myelination) around axons.
Key Distinction/Mechanism: Unlike traditional rodent models that differ significantly from humans in white matter structure and developmental timing, this approach cultures human iPS cell-derived oligodendrocytes on engineered nanofibers mimicking human axons. It measures early structural organization by quantifying the alignment of Claudin-11 (a myelin-specific adhesion molecule), rather than relying solely on conventional terminal differentiation markers.
Major Frameworks/Components:
- iPS Cell Differentiation: Rapid and reproducible generation of human oligodendrocytes via the inducible expression of key transcription factors.
- Nanofiber Scaffold: Use of aligned nanofibers with diameters directly comparable to human axons to recreate the physical microenvironment without the complexities of a neuron co-culture.
- Claudin-11 Readout: Utilization of spatial imaging and transcriptomics to track the highly oriented signaling of Claudin-11 as a quantitative marker for polarized membrane organization.
- Pharmacological Perturbation: An image-based assay system capable of detecting the distinct effects of known myelin enhancers, inhibitors, and white matter toxins.
Branch of Science: Neuroscience, Stem Cell Biology, Bioengineering, and Neuropharmacology.
Future Application: Serving as a reliable, human-specific alternative to animal testing, this platform will accelerate the screening of therapeutic candidates for myelin-repairing drugs and help identify chemical compounds with potential white matter toxicity.
Why It Matters: Disruption of myelin integrity drives numerous devastating neurological conditions, including multiple sclerosis and leukodystrophies. By successfully modeling the critical early phase of human axonal ensheathment, researchers can bridge the translational gap between laboratory models and human trials, paving the way for targeted treatments.
Visualizing Early Myelin Formation Using a Nanofiber-Based Platform: A Human Cell-Based System as a Novel Microphysiological Systems (MPS) Tool
A collaborative research team led by Professor Haruhisa Inoue (CiRA, RIKEN), Junior Associate Professor Takayuki Kondo (CiRA, RIKEN), and Dr. Satoshi Morita (CiRA, RIKEN; formerly of Suntory Wellness Ltd., presently at Suntory Global Innovation Center Ltd.) has developed a human cell-based new approach methodology (NAM) platform. This platform enables the quantitative analysis of oligodendrocyte ensheathment, providing a new tool to study white matter biology and evaluate compounds that modulate early myelination processes.
Oligodendrocytes are glial cells that wrap axons with myelin, an insulating structure essential for efficient signal transmission in the central nervous system. Disruption of oligodendrocyte function and myelin integrity is implicated in a wide range of neurological conditions, including multiple sclerosis, leukodystrophies, neurodegenerative diseases, and drug-induced leukoencephalopathies. Despite their importance, experimental models that reliably reproduce human oligodendrocyte behavior remain limited. Researchers have largely relied on rodent systems, which differ substantially from humans in white matter structure, gene expression, and developmental timing. These species differences have contributed to poor translational success in therapeutic development. Furthermore, the newly developed platform holds significant value as a microphysiological system (MPS), offering a robust alternative to animal-based testing.
In this study, the research team established a reliable and reproducible method to rapidly generate human oligodendrocytes from induced pluripotent stem (iPS) cells using the inducible expression of key transcription factors. To recreate the physical features of axons without the complexity of neuron co-culture, differentiated oligodendrocytes were cultured on aligned nanofibers with diameters comparable to those of human axons. This engineered scaffold provides a defined microenvironment in which oligodendrocyte processes can extend, interact with fiber-like structures, and initiate ensheathment.
Using ultrastructural analyses, live-cell imaging, and transcriptomics, the researchers demonstrated that oligodendrocytes dynamically probe the nanofibers and form wrapping structures reminiscent of early axonal ensheathment. Rather than simply promoting terminal maturation, the nanofiber culture induced a specific molecular program characterized by enhanced lipid metabolism, cell adhesion, and extracellular matrix organization—pathways essential for membrane expansion and structural organization during myelination. Importantly, conventional differentiation markers alone were insufficient to capture these early events.
A central advance of the platform is the use of claudin-11, a myelin-specific adhesion molecule, as a quantitative and spatial readout of structural alignment during ensheathment. Claudin-11 signals became highly oriented along the nanofibers, reflecting the polarized membrane organization that precedes compact myelin formation. By combining claudin-11 alignment with image-based analysis, the researchers established a sensitive assay to evaluate how compounds influence oligodendrocyte structural organization.
As a proof of concept, the platform successfully detected the effects of known enhancers and inhibitors of ensheathment, as well as direct oligodendrocyte toxins associated with clinical white matter injury. These results demonstrate that the system can function both as a screening tool for therapeutic candidates that promote myelin initiation and as an assay to identify compounds with potential white matter toxicity.
While the model focuses on the initial phase of ensheathment rather than fully compacted myelin, this stage represents a critical and previously difficult-to-evaluate step in myelination. By providing a human-specific, experimentally accessible system with quantitative structural readouts, this platform offers a powerful foundation for studying oligodendrocyte pathology, understanding white matter vulnerability, and accelerating the development and safety evaluation of drugs targeting myelin-related disorders.
Published in journal: Stem Cell Reports
Authors: Satoshi Morita, Takayuki Kondo, Keiko Imamura, Yukako Sagara, Kayoko Tsukita, Hisanori Tokuda, Yoshihisa Kaneda, Takayuki Izumo, Yoshihiro Nakao, and Haruhisa Inoue
Source/Credit: Center for iPS Cell Research and Application
Edited by: Scientific Frontline
Reference Number: ns051926_01
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