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Hydrogel-Based Axon Model Improves Early Testing for MS Remyelination Therapies

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Axons—the long, cable‑like projections that relay electrical signals across the nervous system—depend on tightly wrapped layers of myelin to keep those messages fast and reliable. When this insulation is damaged, as in multiple sclerosis (MS) and other neurodegenerative diseases, signal transmission slows and neurons eventually degenerate. Although oligodendrocytes can repair myelin early on in the process, this capacity declines with age and repeated inflammatory attacks, leaving researchers searching for therapies that can restore myelin more effectively.

A team at University College London (UCL) has now developed a more physiologically realistic way to study how myelin forms—and how potential drugs might influence that process. Their new hydrogel‑based axon model, described in Nature Methods in a paper titled “Tunable hydrogel‑based micropillar arrays for myelination studies,” recreates both the geometry and softness of real axons. The platform is designed to address a longstanding problem in the field: many drug candidates that appear promising in rigid, plastic‑based lab models ultimately fail in human trials.

“To stop MS, we need therapies that repair myelin,” said senior author Emad Moeendarbary, PhD, professor of cell mechanics and mechanobiology at UCL and CEO of BioRecode. “Promising drug candidates in the past have failed when tested in human patients. One factor might be that laboratory models do not replicate the basic physical properties of the human brain.”

The UCL team engineered vertical micropillars—each tens of times thinner than a human hair—using a microfabrication process called photolithography that allowed them to precisely tune diameter, spacing, and stiffness. Unlike earlier artificial axons made from hard polymers, these pillars are composed of polyacrylamide hydrogel, a material whose elasticity can be adjusted to match the ~5 kPa softness of native axons. As the authors noted in the paper, the system “mimics the three‑dimensional architecture and softness of axons,” enabling oligodendrocytes to form “multilayered compact myelin” around the pillars.

The researchers seeded the hydrogel pillars with human and rodent oligodendrocytes and tested several candidate remyelination drugs. When the pillars were tuned to realistic softness, drug performance dropped—suggesting that overly rigid models may have produced misleading hits in the past. “Our work suggests that commonly used rigid models, hundreds of times stiffer than real axons, can generate misleading drug hits,” Moeendarbary said. “We believe that our more life-like model can be used as a more robust early test of drug candidates and as a platform to discover new drugs.”

The study also marks the first demonstration of compact, multilayered myelin grown from human oligodendrocytes in a fully hydrogel‑based system. The platform’s design allows high‑content imaging, transcriptomic profiling, and systematic variation of mechanical cues—capabilities that could help researchers dissect how myelin forms and why it fails in disease.

Building such a soft, microscale structure was not trivial. “Hydrogel is a close mimic of living cells… but to fabricate a soft hydrogel at such a small scale is not an easy task,” Moeendarbary noted, crediting the five years of work led by PhD student Soufian Lasli and Claire Vinel, PhD.

By more faithfully recreating the physical environment of the brain, the UCL team hopes their model will provide a more reliable proving ground for remyelination therapies before they reach clinical trials.

The post Hydrogel-Based Axon Model Improves Early Testing for MS Remyelination Therapies appeared first on GEN – Genetic Engineering and Biotechnology News.

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STAT+: At hospital finance conference, a call to end the friction that’s keeping costs high

NATIONAL HARBOR, Md. — At this week’s annual meeting of hospital finance leaders, the exhibit hall was packed with dozens of billing and collections companies. Armed with candy, tote bags, and pens, they smiled at passersby, eager to explain why their tactics would extract the most money from health insurers. 

The sheer number of “revenue cycle” vendors who attended the Healthcare Financial Management Association’s annual conference in Maryland — outnumbering even the hospital attendees, according to a list shared by an organizer — was a visible reminder of the enormous industry built around just paying medical bills. 

The U.S. health care industry spends roughly $200 billion annually on financial transactions: claims processing, payment, collections, and prior authorization. And yet the proliferation of billing vendors seemed to clash with the main theme of HFMA’s conference, affordability, spotlighting the need to simplify the billing process so that health care is less costly and more accessible for patients. 

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NATIONAL HARBOR, Md. — At this week’s annual meeting of hospital finance leaders, the exhibit hall was packed with dozens of billing and collections companies. Armed with candy, tote bags, and pens, they smiled at passersby, eager to explain why their tactics would extract the most money from health insurers. 

The sheer number of “revenue cycle” vendors who attended the Healthcare Financial Management Association’s annual conference in Maryland — outnumbering even the hospital attendees, according to a list shared by an organizer — was a visible reminder of the enormous industry built around just paying medical bills. 

The U.S. health care industry spends roughly $200 billion annually on financial transactions: claims processing, payment, collections, and prior authorization. And yet the proliferation of billing vendors seemed to clash with the main theme of HFMA’s conference, affordability, spotlighting the need to simplify the billing process so that health care is less costly and more accessible for patients. 

Continue to STAT+ to read the full story…

Read More

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Beyond sunshine: Iberia’s biotech moment has arrived with developing capital networks

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Strong science, lower costs and growing capital networks are putting Spain and Portugal on the biotech investment map, even as structural bottlenecks persist, according to two investors.

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Laser‑Driven Phase Contrast Enhances Cryo‑EM Resolution of Small Proteins

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You know when you are at the eye doctor getting an updated prescription, and suddenly the world snaps into sharper focus? Physicists at the University of California (UC), Berkeley, have now done something similar for electron microscopy. By introducing phase contrast into a cryo‑electron microscope, they have delivered dramatically sharper images of some of biology’s smallest and most elusive proteins.

The advance comes from a new laser phase plate (LPP), described in the paper “Laser phase plate improves structure determination of small proteins by cryo‑EM,” which was published recently in Science. Led by physicist Holger Mueller, PhD, of UC Berkeley and Lawrence Berkeley National Laboratory, the team demonstrated that a laser‑driven phase plate can overcome one of cryo‑EM’s most persistent limitations: poor contrast for small proteins.

Cryo-EM images of two proteins, apoferritin and hemoglobin, taken without and with a laser phase plate. The images are analyzed in a computer to produce detailed 3D structures of the proteins. [Holger Müller, Jessie Zhang/UC Berkeley]

Cryo‑EM has transformed structural biology over the past decade, earning a Nobel Prize in 2017 for enabling high‑resolution structures without crystallization. But despite its impact, the technique still struggles with proteins below ~70 kilodaltons—a size range that includes about 90% of the human proteome. “Because of signal-to-noise limitations, the majority of human and animal proteins are too small to be analyzed by these methods [cryo-EM and cryoelectron tomography]. The increase in signal-to-noise ratio provided by this laser phase plate is expected to overcome these important limitations.”

The new LPP begins to address that problem. The LPP uses an intense, continuous‑wave laser to shift the phase of the electron beam itself. This produces true phase contrast without dimming or destabilizing the beam. Mueller described the laser focus as “75 kilowatts focused to a few microns… That’s more powerful than what you use for welding. It has more power than a military laser. It builds up the brightest continuous laser focus ever.”

Installed in a custom Thermo Fisher Titan Krios, the LPP immediately improved the clarity and resolvability of small proteins, including hemoglobin, which sits at the lower limit of what today’s cryo‑EM instruments can handle. As the authors wrote in the abstract: “Here, we show that the laser phase plate (LPP)… enhances the resolution in single-particle reconstruction of small proteins by improving specimen-motion correction, recovery of information from the early frames, as well as particle visualization, 3D classification, and alignment.”

phase plate cover Cryo-EM
A laser (purple) is powerfully amplified by highly polished mirrors and focused on the electron beam (blue) to shift its phase and increase the cryo-EM microscope’s contrast, allowing biologists to image smaller proteins and the crowded structures inside cells. [Sayo Studio]

These improvements were achieved using standard defocus ranges and reconstruction workflows. “For the most challenging cases—small particles, bad specimens—the laser produces a very considerable advantage,” Mueller said.

 

The impact extends beyond single‑particle analysis. Cryo‑electron tomography (cryo‑ET), which assembles multiple angular views of a molecule or protein into a three-dimensional image, stands to benefit even more. “With cryo-ET, we’re looking at small, very complicated cellular material that’s incredibly crowded inside the cell,” said Bridget Carragher, PhD, founding technical director of imaging at Biohub. “It’s like a forest of trees, and you’re trying to find one leaf on one tree in there. Cryo-ET needs a dramatic step forward in contrast, so we can start to see what’s going on inside the cell. That’s what the laser phase plate promises to give us.”

Biohub is developing a dual‑laser version of the system, designed to reduce component wear and minimize aberrations. Meanwhile, Mueller’s team is pushing toward imaging proteins as small as 17 kilodaltons, a threshold that would open access to vast regions of the human proteome previously invisible to cryo‑EM.

“This technology is a step function change for biology,” said Stephani Otte, PhD, Biohub’s vice president of imaging science. “What was once invisible will become visible—and that changes everything about how we understand disease.”

“The bottom line is, if you have a large protein and a really good sample—a fresh one or one frozen without bubbles, for example—you may not need the phase plate to get a single, high-quality image. But for a small protein and a bad sample, laser-on is best,” Mueller said. “This could fill an enormous gap in our knowledge of protein structures that can’t be crystallized or are too small for today’s cryo-EM. And it will be revolutionary for cryo-ET.”

The post Laser‑Driven Phase Contrast Enhances Cryo‑EM Resolution of Small Proteins appeared first on GEN – Genetic Engineering and Biotechnology News.

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