A restored cornea grown from human ABCB5-positive limbal stem cells

A restored, clear cornea grown from ABCB5-positive limbal stem cells. (Image courtesy of the researchers)

Severe burns, chemical injury and certain diseases can cause blindness by clouding the eyes’ corneas and killing off a precious population of stem cells that help maintain them. In the past, doctors have tried to regrow corneal tissue by transplanting cells from limbal tissue—found at the border between the cornea and the white of the eye. But they didn’t know whether the tissue contained enough of the active ingredient: limbal stem cells.

How cancer research led to a regenerative treatment for blindness.

Results have therefore been mixed. “Limbal stem cells are very rare, and successful transplants are dependent on these rare cells,” says Bruce Ksander, PhD, of the Massachusetts Eye and Ear/Schepens Eye Research Institute. “If you have a limbal stem cell deficiency and receive a transplant that does not contain stem cells, the cornea will become opaque again.”

Limbal stem cells have been sought for over a decade. That’s where a “tracer” molecule called ABCB5—first studied in the context of cancer—comes in. Full story »

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Fat cells from mesenchymal stem cell transplant

The fat cells shown in yellow are descended from transplanted human mesenchymal stem cells (green) inside of a mouse after co-transplantation. The red stain shows native mouse fat cells.(Courtesy Juan Melero-Martin)

Joseph Caputo originally wrote this post for the Harvard Stem Cell Institute (HSCI). Vector editor Nancy Fliesler contributed.

Stem cell scientists had what first appeared to be an easy win for regenerative medicine when they discovered mesenchymal stem cells several decades ago. These cells, found in the bone marrow, can give rise to bone, fat and muscle tissue, and have been used in hundreds of clinical trials for tissue repair.

Uses range from tissue protection in heart attack and stroke to immune modification in multiple sclerosis and diabetes. Unfortunately, the results of these trials have been underwhelming. One challenge is that these stem cells don’t stick around in the body long enough to benefit the patient. Full story »

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Old car aging blood cell hematopoietic stem cell blood disorder Derrick Rossi

Like an old, unused car, our aging blood stem cells can accumulate damage over time that they can't fully repair.

My first car was my grandfather’s 1980 Chevrolet Malibu. For about two years before my family gave it to me, it sat unused in Grandpa’s garage—just enough time for all of the belts and hoses to rot and the battery to trickle down to nothing.

Why am I telling this story? Because it’s much like what happens to the DNA in our blood-forming stem cells as we age.

Hematopoietic stem cells (HSCs) spend very little of their lives in an active, cycling state. Much of the time they’re quiescent or dormant, keeping their molecular and metabolic processes dialed down. These quiet periods allow the cells to conserve resources, but also give time an opportunity to wear away at their genes.

“DNA damage doesn’t just arise from mistakes during replication,” explains Derrick Rossi, PhD, a stem cell biology researcher with Boston Children’s Hospital’s Program in Cellular and Molecular Medicine. “There are many ways for damage to occur during periods of inactivity, such as reactions with byproducts of our oxidative metabolism.”

The canonical view has been that HSCs always keep one eye open for DNA damage and repair it, even when dormant. But in a study recently published in Cell Stem Cell, Rossi and his team found evidence to the contrary­­—which might tell us something about age-related blood cancers and blood disorders. Full story »

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Tracking patients between clinical visits

A randomized trial will soon test whether web-based updates from parents and teachers improve outcomes in ADHD, autism and more.

Eugenia Chan, MD, MPH, is a developmental-behavioral pediatrician and health services researcher in the Division of Developmental Medicine at Boston Children’s Hospital. She runs the Developmental Medicine Centers ADHD Program and is co-developer of ICISS Health, a web-based disease monitoring and management system.

When I set out with my collaborator Eric Fleegler, MD, MPH, to build a web-based tracking system for children with attention deficit hyperactivity disorder (ADHD), we focused on a single problem—getting parents and teachers to fill out symptom questionnaires in time to help doctors make informed clinical decisions at follow-up visits. We had no inkling of the possibilities that this kind of software platform could hold, or how it might grow in the future. Full story »

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spina bifida myelomeningocele

Prenatal cell therapy could avoid the need for invasive surgery to repair myelomeningocele.

The neural tube, which becomes the spinal cord and brain, is supposed to close during the first month of prenatal development. In children with spina bifida, it doesn’t close completely, leaving the nerves of the spinal cord exposed and subject to damage. The most common and serious form of spina bifida, myelomeningocele, sets a child up for lifelong disability, causing complications such as hydrocephalus, leg paralysis, and loss of bladder and bowel control.

New research from Boston Children’s Hospital, though still in animal models, suggests that standard amniocentesis, followed by one or more injections of cells into the womb, could be enough to at least partially repair spina bifida prenatally.

Currently, the standard procedure is to operate on infants soon after delivery. Full story »

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Alina Morris, Archivist, Boston Children’s Hospital, contributed to this post.

In 1914, Boston Children’s Hospital, then simply called The Children’s Hospital, constructed the 145-bed Hunnewell Building, joining Harvard Medical School as one of several founding members of the Longwood Medical Area.

As the hospital’s oldest continuously occupied building, Hunnewell has presided over many of the century’s great medical advances and innovations. We celebrate a portion of them in this slideshow honoring Hunnewell’s 100th anniversary—and invite you to help write the next 100 years of history October 30-31 at Boston Children’s Global Pediatric Innovation Summit + Awards 2014.

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Surgical Sam beating heart pediatric trainer mannequin simulation Simulator Program The Chamberlain GroupWe often see medical magic in Hollywood, but it’s not often we see Hollywood magic brought into medicine. Now, Boston Children’s Hospital’s Simulator Program and special-effects collaborators at The Chamberlain Group (TCG) have done just that.

Simulation has become a key component in team training, crisis management, surgical practice and other medical training activities. With simulation, medical teams can add to and hone their skills in an environment where people can make mistakes without risking patient harm—”practicing before game time,” says Boston Children’s critical care specialist Peter Weinstock, MD, PhD, who runs the Simulator Program.

Mannequins are a key part of simulation, and Weinstock’s team, working together with companies, designers and engineers, has developed eerily lifelike ones that can bleed and “respond” to interventions based on computer commands from a technician.

But there are some things Weinstock’s mannequins haven’t been able to capture up to now, like the movements of a beating heart.

That’s where TCG and a new mannequin called Surgical Sam come in. Full story »

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Three teenagers wearing hospital masks flu influenza healthmap social media twitter digital epidemiology digital disease detectionElaine Nsoesie, PhD, is a research fellow at Boston Children’s Hospital’s HealthMap, Harvard Medical School and Virginia Bioinformatics Institute. In this post, which originally appeared on HealthMap’s Disease Daily, Nsoesie looks at the trend of detecting disease digitally by monitoring mentions on social media. She delves into one of the major limitations of this technique—namely telling those who are curious about a disease apart from those who actually have it.

There are plenty of studies about tracking diseases (such as influenza) using digital data sources, which is awesome! However, many of these studies focus solely on matching the trends in the digital data sources (for example, searches on disease-related terms, or how frequently certain disease-related terms are mentioned on social media over time, etc.) to data from official sources such as the Centers for Disease Control and Prevention. Although this approach is useful in telling us about the possible utility of these data, there are several limitations. One of the main limitations is the difficulty in distinguishing between data generated by healthy individuals and individuals who are actually sick. In other words, how can we tell whether someone who searches Google or Wikipedia for influenza is sick or just curious about the flu?

Researchers at Penn State University have developed a system that seeks to deal with this limitation. We spoke to the lead author, Todd Bodnar, about the study titled, On the Ground Validation of Online Diagnosis with Twitter and Medical Records. Full story »

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music and executive functionMy daughter just surprised me by signing up for fifth grade band starting this fall. To my further delight, some new research—using both cognitive testing and brain imaging—suggests that as she practices her clarinet, she also may be honing her executive functions.

Like a CEO who’s on top of her game, executive functions—separate from IQ—are those high-level brain functions that enable us to quickly process and retain information, curb impulsive behaviors, plan, make good choices, solve problems and adjust to changing cognitive demands. While it’s already clear that musical training relates to cognitive abilities, few previous studies have looked at its effects on executive functions specifically.

The study, appearing this week in PLOS ONE, compared children with and without regular musical training, as well as adults. To the researchers’ knowledge, it’s the first such study to use functional MRI (fMRI) of brain areas associated with executive function and to adjust for socioeconomic factors. Full story »

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Bioengineered blood vessels

A bioengineered network of blood vessels

Juan Melero-Martin, PhD, runs a cell biology and bioengineering lab in the department of Cardiac Surgery at Boston Children’s Hospital. In May, he received an Early Career Investigator Award from Bayer HealthCare, part of the prestigious Bayer Hemophilia Award.

In 1982, insulin became the first FDA-approved protein drug created through recombinant DNA technology. It was made by inserting the human insulin gene into a bacterial cell’s DNA, multiplying the bacteria and capturing and purifying the human insulin in bioreactors. Full story »

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