In a landmark advancement promising to reshape the landscape of neurodegenerative disease research, scientists at University College London (UCL) have developed an innovative physical model of axons—the microscopic nerve fibers critical for brain and spinal cord function—that mimics the human nervous system with unprecedented accuracy. This breakthrough addresses a longstanding challenge in drug discovery for conditions such as multiple sclerosis (MS), where traditional laboratory models have often fallen short, leading to high failure rates in clinical trials.
The crux of this innovation lies in fabricating a model that not only replicates the physical architecture of axons but also their mechanical properties, a factor previously overlooked in drug screening. Axons, ensheathed by the protective myelin produced by oligodendrocytes, are essential conduits for electrical signals in the nervous system. In MS and related neurodegenerative diseases, myelin degradation disrupts neural communication, causing debilitating symptoms. The UCL team’s model, described in a recent paper published in Nature Methods, employs hydrogel-based micropillars that closely match the softness and structural characteristics of real axons—a stark contrast to the rigid plastic models traditionally used.
This hydrogel fabrication marks a profound technical achievement. Unlike plastic, which is orders of magnitude stiffer than biological tissue, hydrogel boasts a high water content and porosity, closely resembling living cells’ extracellular environment. Utilizing photolithography, the researchers crafted micro-scale molds to shape water-filled hydrogel into pillars tens of times thinner than a human hair. These micropillars emulate the delicate mechanical milieu wherein oligodendrocytes operate, allowing for more physiologically relevant interactions between the cells and their substrate.
Once these axon mimics were established, the research team cultured oligodendrocytes derived from both human and rodent sources around the micropillars to induce myelin formation. Crucially, this represents the first successful laboratory cultivation of myelin from human cells within a controlled, biomimetic system. The team then introduced various candidate drugs designed to stimulate myelin repair or regeneration, assessing their effectiveness in promoting myelin layering on the flexible hydrogel pillars.
The findings were illuminating and somewhat cautionary. Drugs that previously showed promise in conventional rigid models demonstrated diminished efficacy against the more life-like softer axons. This suggests that the rigidity of oversimplified models may have contributed to the proliferation of false-positive drug candidates, which ultimately failed when tested in human trials. The UCL model’s closer approximation to human tissue mechanics reveals the nuances that were missed and underscores the necessity of such sophisticated systems for early-stage drug validation.
Professor Emad Moeendarbary, senior author and expert in cellular mechanics, emphasized the significance of this work, stating that the replication of the brain’s physical microenvironment is crucial for reliable drug discovery in MS. He highlighted that conventional models’ stiffness—hundreds of times greater than actual axons—likely generates misleading results, potentially misguiding research investment and delaying clinical progress. The new model paves the way for more robust preclinical testing, reducing costly failures downstream.
Beyond MS, this approach has broader implications for understanding and treating other neurodegenerative disorders characterized by myelin damage, including Alzheimer’s, Parkinson’s, and motor neurone diseases. Myelin repair mechanisms invariably falter as these conditions progress, exacerbating neural dysfunction and cell death. By enabling detailed examination of myelinogenesis in a controlled yet realistic setting, this model offers a powerful platform for probing disease mechanisms and therapeutic responses.
One of the challenges surmounted by the researchers was engineering hydrogels fine enough to mimic axonal diameter while maintaining mechanical softness. Hydrogels must balance porosity with structural integrity—a demanding feat at microscale dimensions. The iterative optimization, led by PhD candidate Soufian Lasli and Dr. Claire Vinel, spanned five years of meticulous fabrication, biological validation, and refinement, culminating in a system that offers unprecedented fidelity to native nerve fiber properties.
This model’s adoption could revolutionize early drug screening pipelines by integrating both chemical and physical parameters impacting oligodendrocyte behavior. Researchers can now systematically vary stiffness and analyze how biophysical cues interface with biochemical signals—a multi-dimensional approach previously inaccessible. This capacity to deconstruct complex interactions holds promise for identifying novel molecular targets and compounds that genuinely enhance remyelination.
Moreover, the interdisciplinary nature of this study, combining mechanical engineering, molecular cell biology, neuroscience, and pharmacology, exemplifies the collaborative ethos needed to tackle complex biomedical problems. Contributions hail from multiple UCL faculties and partner institutions such as Universidad de Malaga and the University of Nottingham, illustrating the global impetus behind improving neurological therapeutics.
In summary, this new hydrogel-based axon model represents a paradigm shift in neurodegenerative disease research. It provides an essential tool for bridging the gap between in vitro experimentation and clinical efficacy, thereby accelerating the pathway to effective treatments for MS and other devastating brain disorders. By faithfully mirroring the brain’s microenvironment, the model holds promise not only for drug discovery but also for fundamental insights into the biology of myelin and nerve fiber regeneration.
Subject of Research: Development of a life-like hydrogel-based model of axons for enhanced drug discovery in neurodegenerative diseases
Article Title: Life-like Hydrogel Axon Model Unveils New Paradigms in Multiple Sclerosis Drug Discovery
News Publication Date: 2024
Web References: http://dx.doi.org/10.1038/s41592-026-03048-3
References: Soufian Lasli et al / Nature Methods
Image Credits: Soufian Lasli et al / Nature Methods
Keywords: Neurodegenerative diseases, Multiple sclerosis, Axon regeneration, Regeneration, Engineering, Drug discovery, Drug development, Myelin repair, Hydrogel, Cellular mechanics
