Stem cell stories that caught our eye: screening for cancer drugs for kids, better CRISPR gene editing and funding for chimeras

Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.

Stem cells screen drugs for kids’ rare tumor.  A team at Johns Hopkins University in Baltimore has transformed stem cells into a particularly nasty form of pediatric brain cancer, medulloblastoma. They then used those cells to figure out what drugs might defeat the tumor and found one existing drug, approved for advanced breast cancer, that seemed to be a good candidate.

While about two-thirds of medulloblastoma patients do well with standard therapy, those in a class called “group 3” often do not survive. But the rarity of that condition, meant the researcher could not use what has become a common route to determining effective drugs: comparing the genetic profile of the cancer with the genetic profile of banks of cancer cells that have already have been tested against existing cancer drugs. There are not enough Group 3 samples in the banks to take that route.

So, the Hopkins team used a two-step process for the drug search. They first inserted genes associated with the Group 3 cancers into stem cells and let the cells begin to transform into tumors. After making sure their stem cell tumors genetically looked and behaved like medulloblastoma the researchers compared genetic “signatures” from those cells with the signatures of cells in the large databases of other cancers.

eric raabe hopkins

Raabe

“We wanted to find whether the cells we created matched any of these existing signatures, because if they did, then we would have some idea of what kinds of drugs are more or most likely to kill these cells,” said Eric Raabe in a university release posted by ScienceDaily. “We didn’t have to do the laborious screening to test 100,000 compounds against our own cells.”

Raabe suggested this system might work to create a short cut to finding best therapies for other rare tumors as well.

 

Combining tricks from two critters.  This article does not address stem cells directly, but rather a widely popular gene editing technique many hope to use with stem cell therapies, the system known as CRISPR.  But before that can happen, researchers need to figure out how to eliminate or minimize pesky “off-target” gene editing, when the genetic scissor slices the DNA in a spot that was not intended.

CRISPR technology borrows from bacteria. About 40 percent of bacteria immune systems use CRISPR’s genetic elements to recognize foreign genes such as phages, the viruses that can kill or tag along in bacteria. Scientists generally pair CRISPR’s ability to recognize specific gene segments, with great specificity, with the nuclease, or genetic scissor, called CAS9. But that scissor is not quite as precise. So, a team at Kobe University in Japan borrowed an immune system trick from a second critter, a sea lamprey, sometimes incorrectly called an eel. The result was a much more precise gene editing tool.

Lamprey

The lamprey gene editing tool they borrowed is based on an enzyme called a deaminase. The lamprey uses the enzyme to create breaks in the genes for its immune system’s antibodies in order to have a more diverse immune system able to recognize more outside pathogens. That deaminase tool turns out to go a long way toward making CRISPR precise enough to be considered for use in a therapy.

The Japanese work published in the journal Science, marks the second time researchers have recently published a way to use a deaminase tool to improve CRISPR. The prior work came from the lab of Harvard’s George Church, who is quoted extensively in an article about the latest study in The Scientist. Be warned, Church likes detail and this is a pretty technical article unless you are a science nerd like us at The Stem Cellar.

 

Animals with bits of human get green light.  A flurry of stories came out a few months ago when a reporter realized that while the National Institutes of Health (NIH) had a moratorium on creating chimeras—animal embryos that are partly human—CIRM was still funding the work. Now, NIH has announced plans to lift that moratorium with several safeguards in place to make sure certain projects that raise ethical issues don’t get approved. We are glad to have company in funding this potentially life-saving research.

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Researchers working in the area have two main goals. They want to create better models of human disease, and they want to grow human organs in animals such as pigs to alleviate the current shortage of donor organs and help the thousands of patients who die each year waiting for a donor.

NPR aired a story that did a good job describing the safeguards and the types of projects that would not be allowed. It quoted Carrie Wolinetz, the NIH associate director for science policy:

 “At the end of the day, we want to make sure this research progresses because it’s very important to our understanding of disease. It’s important to our mission to improve human health. But we also want to make sure there’s an extra set of eyes on these projects because they do have this ethical set of concerns associated with them.”

Forbes posted a story online that took great liberty with comparisons to science fiction, but had fun with it and in the end valued the potential for the work. And the public does have a chance to weigh in on the ethical issues as NIH has published a call for comments in the Federal Register.

Unlocking the secrets of how stem cells decide what kind of cell they’re going to be

Laszlo Nagy, Ph.D., M.D.

Laszlo Nagy, Ph.D., M.D.: Sanford Burnham Prebys Medical Discovery Institute

Before joining CIRM I thought OCT4 was a date on the calendar. But a new study says it may be a lot closer to a date with destiny, because this study says OCT4 helps determine what kinds of cell a stem cell will become.

Now, before we go any further I should explain for people who have as strong a science background as I do – namely none – that OCT4 is a transcription factor, this is a protein that helps regulate gene activity by turning certain genes on at certain points, and off at others.

The new study, by researches at Sanford Burnham Prebys Medical Discovery Institute (SBP), found that OCT4 plays a critical role in priming genes that cause stem cells to differentiate or change into other kinds of cells.

Why is this important? Well, as we search for new ways of treating a wide variety of different diseases we need to find the most efficient and effective way of turning stem cells into the kind of cells we need to regenerate or replace damaged tissue. By understanding the mechanisms that determine how a stem cell differentiates, we can better understand what we need to do in the lab to generate the specific kinds of cells needed to replace those damaged by, say, heart disease or cancer.

The study, published in the journal Molecular Cell, shows how OCT4 works with other transcription factors, sometimes directing a cell to go in one direction, sometimes in another. For example, it collaborates with a vitamin A (aka retinoic acid) receptor (RAR) to convert a stem cell into a neuronal precursor, a kind of early stage brain cell. However, if OCT4 interacts with another transcription factor called beta-catenin then the stem cell goes in another regulatory direction altogether.

In an interview with PhysOrg News, senior author Laszlo Nagy said this finding could help develop more effective methods for producing specific cell types to be used in therapies:

“Our findings suggest a general principle for how the same differentiation signal induces distinct transitions in various types of cells. Whereas in stem cells, OCT4 recruits the RAR to neuronal genes, in bone marrow cells, another transcription factor would recruit RAR to genes for the granulocyte program. Which factors determine the effects of differentiation signals in bone marrow cells – and other cell types – remains to be determined.”

In a way it’s like programming all the different devices that are attached to your TV at home. If you hit a certain combination of buttons you get to one set of stations, hit another combination and you get to Netflix. Same basic set up, but completely different destinations.

“In a sense, we’ve found the code for stem cells that links the input—signals like vitamin A and Wnt—to the output—cell type. Now we plan to explore whether other transcription factors behave similarly to OCT4—that is, to find the code in more mature cell types.”

 

 

Stem cells maturing into nerve produce a compound that speeds the process

Getting pluripotent stem cells—those early stage stem cells that can make any tissue—to actually make the cell type you want can be quite tricky. I have written before that it takes a village to raise a stem cell because they respond to everything around them from the physical pressure and rigidity of their environment to any number of already present or added chemical factors. Now, a CIRM-funded team at the University of California, Los Angeles, has shown they respond to a compound made in the maturation process itself.

As stem cells mature into specific tissue their metabolism speeds up and they convert sugar to energy more efficiently. In the process they produce compounds, various so-called metabolites, and it turns out those metabolites can be part of a feedback loop that speeds the maturation process. In particular, the UCLA team looked at the metabolite alpha-ketoglutarate and when they added it to it to stem cells in the process of turning into nerve cells in a dish, the process proceeded more quickly.

 

UCLA metabolite video

Lead researcher Tara TeSlaa describes the work in a video

Prior research had shown alpha-ketoglutarate gets involved in regulating gene activity. The Los Angeles researchers did some testing and determined that the metabolite was indeed turning off genes needed to keep the stem cells in a stem cell state and turning on genes needed to mature the cells into nerves.

 “Until very recently, metabolites have been overlooked as a way to help pluripotent stem cells differentiate,” said Michael Teitell, the senior author on the study in a university press release. “This work helps to change that view.”

The research published in Cell Metabolism showed a five to 40 percent improvement in the rate that cells matured into desired tissues. These results were based on lab cultures that already had the standard factors used to grow nerve cells, but also contained added alpha-ketoglutarate to see what a little extra of the metabolite would do. While they were looking only at nerve cells in this experiment, they speculated that the same metabolite would have similar effects in lab cultures using standard factors for growing other cell types.

The team now plans to try to determine exactly which genes the metabolite regulates. Every tidbit of information on how cells mature into desired tissues, makes it more likely we will be able to efficiently make those tissues to repair and replace tissues damaged by disease for patients in need.

Stem Cells May Help Endangered Species Live Long and Prosper

It’s the year 2286. The transmission signal of an alien space probe is wreaking havoc on Earth, knocking out the worldwide power grid and causing massive storms. It turns out the mysterious orbiting probe is trying to communicate with humpback whales through whale song and the devastation won’t stop until contact is made. But there’s a tiny problem: in that future, the humpback has long since become extinct. So the captain and crew travel back in time to snag two whales and save 23rd century civilization. Phew!

My fellow science fiction nerds will recognize that plot line from 1986’s Star Trek IV: A Voyage Home. It’s pure fantasy and yet there is a real lesson for our present day world: you shouldn’t underestimate how the extinction of a species will impact our world. For instance, the collapse and potential extinction of the bee population and other pollinators threatens to destabilize our global food supply.

Northern White Rhinos: At the Brink of Extinction
Beyond how it may affect us humans, I think there’s also a moral obligation to save endangered species that have dwindled in number directly due to human actions. It may be too late for the northern white rhino though. Because their horns are highly sought after as a status symbol and for use in traditional medicine, poachers have wiped out the population and now only three – Sudan, Najin and Fatu (grandfather, mother and daughter) – exist in the world. Sadly, none of them can breed naturally so they quietly graze in a Kenyan conservation park as their species heads towards extinction.

whiterhino

One of the three remaining northern white rhinos in the world (Image source: The Guardian)

Jeanne Loring, a CIRM grantee and professor at The Scripps Research Institute, still sees a glimmer of hope in the form of stem cells. In an essay published yesterday in Genetic Engineering and Biotechnology News, Loring describes her research team’s efforts to apply stem cell technology toward saving the Northern White Rhino and other endangered species.

Their efforts began about ten years ago in 2007, the same year that Shinya Yamanaka’s lab first reported that human fibroblasts, collected from a skin sample, can be reprogrammed into an embryonic stem cell-like state with the capacity to indefinitely make copies of themselves and to specialize into almost every cell type of the body. The properties of these induced pluripotent stem (iPS) cells have provided an important means for studying all sorts of human diseases in a lab dish and for deriving potential cell therapies.

FrozenZoo® and iPS Cells: A Modern Day Noah’s Ark?

But it was a free tour at the San Diego Safari Park just two months after Yamanka’s discovery which inspired the Loring lab to chart this additional research path using iPS cells. In exchange for the free safari ride, the team reciprocated by chatting with Oliver Ryder, director of the San Diego Zoo Institute for Conservation Research, about using stem cells to help save endangered species. Ryder’s institute runs the FrozenZoo® a cell and tissue bank containing thousands of frozen samples from a diverse set of species. In her essay, Loring recounts what happened after the visit:

“It was obvious to us: why not try to reprogram fibroblasts from the FrozenZoo®? When my group returned to the lab from the safari, I asked them: who would like to try to reprogram fibroblasts from an endangered species? It was far from a safe bet, but a young postdoctoral researcher who had recently joined my lab from Israel said that she’d love to give it a try. Inbar Friedrich Ben-Nun spent the next couple of years trying out methods in parallel on human cells and fibroblasts from the zoo. We chose fibroblasts from the drill because it is [an endangered] primate, making it more likely that the technology used for humans would work.

Oliver [Ryder] chose the northern white rhino, a particular favorite of his, and one of the world’s most endangered mammals.  Through hard work and insight, Inbar reprogrammed both species, and in 2011, we published the first report of making iPSCs from endangered species (Ben-Nun, et al., 2011). Nature Methods featured our work, with a cover illustration of an ark stuffed with endangered animals.”

 

 

 

So how exactly would these iPS cells be used to save the northern white rhino and other animals from the brink of extinction? Last December, Ben-Nun along with 20 other scientists and zoologists from four continents met in Vienna to map out a strategy. They published their plan on May 3rd in Zoo Biology.

The Stem Cell-Based Plan to Save the Northern White
In the first phase, an in vitro fertilization (IVF) procedure for the rhino – never before attempted – will be worked out. Frozen sperm samples from four now-deceased rhinos plus one sample from Sudan are ready for IVF. Researchers then hope to collect eggs from Najin and Fatu and implant embryos in surrogates of a related species, the southern white rhino. However, even if IVF is successful, the offspring would not represent enough genetic diversity to ultimately thrive as a species in the wild. So in the second phase, iPS cells will be generated using tissue fibroblast samples from several more northern whites that were banked in The FrozenZoo®. Those iPS cells will be specialized into sperm and eggs to provide a larger, more diverse set of embryos which again will be implanted in surrogate rhinos. Breeding animals using iPS-derived sperm and eggs has only been successful in mice so much work remains.

“Does this plan have any chance of succeeding?” Loring asks. Her response is cautiously optimistic:

“I know it will be difficult, but I think it’s not impossible. Perhaps the most important advance is that such a diverse group agreed on a plan—it wasn’t just a stem cell biologist like me imagining how the cells might be used, but rather a whole chain of experts who can imagine how to accomplish each step.”

 

Not all experts agree with this strategy. In a Nature News interview back in May, Michael Knight, chair of the International Union for Conservation Nature’s African Rhino Specialist Group, expressed concerns that the effort is misdirected:

“It’s Star Trek-type science. They should not be pushing this idea that they’re saving a species. If you want to save a [rhino] species, put your money into southern white conservation.”

IMHO
Knight’s point is well-taken that conventional conservation approaches are critical to ensure that the southern white rhino doesn’t meet the same disastrous fate as the northern white. But if the funding is available, it seems worth the effort to also attempt this innovative iPS strategy, a technology that’s deep in development now and not awaiting Captain Kirk’s distant Star Trek future.

Tunable hydrogels guide stem cell differentiation

Differentiating stem cells into mature cells of adult tissue involves many intricate steps to get them to develop into the right cell types. You could compare the process to the careful adjustments you make when tuning a guitar.

In the body, stem cells receive cues from their surrounding environment to mature into specific types of cells. These cues can be biochemical – molecules like lipids, growth factors and metabolites (products of cell metabolism) – or they can be physical – the stiffness of surrounding tissue. But these molecules and structures aren’t always present when scientists attempt to differentiate stem cells outside the body, say in a cell culture dish.

One way researchers are improving the methods for differentiating stem cells outside the body is by using biomaterials such as hydrogels that mimic properties of the structures and molecules found naturally in various stem cell niches that aid in their maturation to adult cell types.

A CIRM-funded study published last week in the journal Chem, has developed “tunable hydrogels” that direct stem cells to differentiate into brain, cartilage and bone cells based on adjustments to the hydrogel’s stiffness and metabolite profile. The work was a collaboration between scientists in New York and in Scotland and one of the co-authors, Bruno Péault, was a CIRM-funded scientist in California during the time of the study.

Hydrogels with different stiffness' direct stem cells to differentiate into different types of tissue. (Chem)

Hydrogels with different stiffness’ direct stem cells to differentiate into different types of tissue. (Chem)

Tuning gels to differentiate stem cells

The scientists started with hydrogels composed of nanofibers that varied in stiffness and observed that perivascular stem cells (from the connective tissue surrounding blood vessels) grown in more flexible gels turned into brain cells and those that were grown in stiffer gels turned into bone cells. The stiffness of these different hydrogels was comparable to that of actual brain and bone tissue, which indicated that stiffness is important for stem cell fate.

But stiffness alone isn’t responsible for directing stem cells into different cell fates – biochemical metabolites are also key to this process. The authors also analyzed the metabolite profiles of the different hydrogels to determine which metabolites were important for stem cell differentiation. They tested different concentrations of over 600 metabolites in the hydrogels during stem cell differentiation and found that certain lipids like lysophosphatidic acid and cholesterol sulfate were essential for differentiation into cartilage and bone tissue respectively. When these specific lipids were added to regular stem cell cultures (without hydrogels), the stem cells differentiated towards cartilage and bone cells. Thus they concluded that both the metabolite profile and the stiffness of hydrogels are important for directing stem cell differentiation.

Interestingly, the authors also showed how metabolites like cholesterol sulfate could influence and activate transcription factors – proteins that also direct stem cell differentiation – which controlled the activation of bone-related genes. This finding suggests a relationship between metabolite expression and transcription factor activity and offers a simpler way to activate transcription factors important for stem cell fate.

Big picture of tunable hydrogels

Looking at the big picture, this study offers a useful strategy to identify molecules that promote formation of specific tissue types from stem cells. These molecules could be potential drug candidates that could aid in regenerating bone and cartilage tissue for patients with osteoporosis or osteoarthritis.

Co-senior author on the study and professor at the University of Glasgow, Matthew Dalby, who was interviewed by Science Magazine elaborated on the importance of their study:

Matthew Dalby

Matthew Dalby

“Our ambition is to simplify drug discovery — by using the cell’s own metabolites as drug candidates. For example, cholesterol sulfate, which our rigid gel revealed as critical to bone cell differentiation, could be a safer solution (e.g., minimal off-target effects) for treating osteoporosis, spinal fusion, and other bone-related conditions. Presently, growth factors are used, but these can lead to unwanted collateral damage, and government agencies in the UK and US have published warnings against their use.”

Rein Ulijn, co-senior author with Dalby and professor at the City University of New York and University of Strathclyde, concluded by emphasizing how the metabolites they identified could be potential drug candidates and would pass regulatory approval if shown to be safe and effective:

Rein Ulijn

Rein Ulijn

“That you can use simple metabolites like cholesterol sulfate, which is readily available, to induce differentiation is in my view very powerful if you think about this as a potential drug candidate. These metabolites are inherently biocompatible, so the hurdles to approval are going to be much lower compared to those associated with completely new chemical entities.”

In the future, both teams plan to further “tune” their hydrogels to mimic more complex tissue environments that incorporate additional properties besides stiffness in hopes of creating more relevant 3D micro-environments to model the stem cell niche.

Stem cell stories that caught our eye: potential glaucoma therapy, Parkinson’s model, clinical trial list, cancer immune therapy

Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.

Stem cells may be option in glaucoma.  A few (potentially) blind mice did not run fast enough in an Iowa lab. But lucky for them they did not run into a farmer’s wife wielding a knife. Instead they had their eye sight saved by a team at the University of Iowa that corrected the plumbing in the back of their eyes with stem cells. They had a rodent version of glaucoma, which allows fluid to build up in the eye causing pressure that eventually damages the optic nerve and leads to blindness.

human eye

The fluid buildup results from a breakdown of the trabecular meshwork, a patch of cells that drains fluid from the eye. The Iowa researchers repaired that highly valuable patch with cells grown from iPS type stem cells created by reprogramming adult cells into an embryonic-like state. The trick with any early stage stem cell is getting it to mature into the desired tissue. This team pulled that off by growing the cells in a culture dish that had previously housed trabecular meshwork cells, which must have left behind some chemical signals that directed the growth of the stem cells.

The cells restored proper drainage in the mice. Also notable, the cells not only acted to replace damaged tissue directly, but they also seem to have summoned the eye’s own healing powers to do more repair. The research team also worked at the university affiliated Veterans Affairs Hospital, and the VA system issued a press release on the work published in the Proceedings of the National Academy of sciences, which was posted by Science Codex.

 

A “mini-brain” from a key area.   The brain is far from a uniform organ. Its many distinct divisions have very different functions. A few research teams have succeeded in coaxing stem cells into forming multi-layered clumps of cells referred to as “brain organoids” that mimic some brain activity, but those have generally been parts of the brain near the surface responsible for speech, learning and memory. Now a team in Singapore has created an organoid that shows activity of the mid-brain, that deep central highway for signals key to vision, hearing and movement.

The midbrain houses the dopamine nerves damaged or lost in Parkinson’s disease, so the mini-brains in lab dishes become immediate candidates for studying potential therapies and they are likely to provide more accurate results than current animal models.

 “Considering one of the biggest challenges we face in PD research is the lack of accessibility to the human brains, we have achieved a significant step forward. The midbrain organoids display great potential in replacing animals’ brains which are currently used in research,” said Ng Huck Hui of A*Star’s Genome Institute of Singapore where the research was conducted in a press release posted by Nanowerk.

The website Mashable had a reporter at the press conference in Singapore when the institute announce the publication of the research in Cell Stem Cell. They have some nice photos of the organoids as well as a microscopic image showing the cells containing a black pigment typical of midbrain cells, one of the bits of proof the team needed to show they created what they wanted.

 

Stem cell clinical trials listings.  Not a day goes by that I, or one of my colleagues, do not refer a desperate patient or family member—often several per day—to the web site clinicaltrials.gov. We do it with a bit of unease and usually some caveats but it is the only resource out there providing any kind of searchable listing of clinical trials. Not everything listed at this site maintained by the National Institutes of Health (NIH) is a great clinical trial. NIH maintains the site, and sets certain baseline criteria to be listed, but the agency does not vet postings.

Over the past year a new controversy has cropped up at the site. A number of for profit clinics have registered trials that require patients to pay many thousands of dollars for the experimental stem cell procedure.  Generally, in clinical trials, participation is free for patients. Kaiser Health News, an independent news wire supported by the Kaiser Family Foundation distributed a story this week on the phenomenon that was picked up by a few outlets including the Washington Post. But the version with the best links to added information ran in Stat, an online health industry portal developed by The Boston Globe, which has become one of my favorite morning reads.

The story leads with an anecdote about Linda Smith who went to the trials site to look for stem cell therapies for her arthritic knees. She found a listing from StemGenex and called the listed contact only to find out she would first have to pay $14,000 for the experimental treatment. The company told the author that they are not charging for participation in the posted clinical trial because it only covers the observation phase after the therapy, not the procedure itself. The reporter found multiple critics who suggested the company was splitting hairs a bit too finely with that explanation.

But the NIH came in for just as much criticism for allowing those trials to be listed at all. The web site already requires organizations listing trials to disclose information about the committees that oversee the safety of the patients in the trial, and critics said they should also demand disclosure of payment requirements, or outright ban such trials from the site.

Paul-Knoepfler-2013 “The average patient and even people in health care … kind of let their guard down when they’re in that database. It’s like, ‘If a trial is listed here, it must be OK,’” said Paul Knoepfler, a CIRM grantee and fellow blogger at the University of California, Davis. “Most people don’t realize that creeping into that database are some trials whose main goal is to generate profit.”

The NIH representative quoted in the article made it sound like the agency was open to making some changes. But no promises were made.

Added note 7/30. While this post factually describes an article that appeared in the mainstream media, the role of this column, I should add that while I did not take a position on paid trials, I am thrilled Stemgenex is collecting data and look forward to them sharing that data in a timely, peer-reviewed fashion.

 

Off the shelf T cells.  We at CIRM got some good news this week. We always like it when we see an announcement that technology from a researcher we have supported gets licensed to a company. That commercialization moves it a giant step closer to helping patients.

This week, Kite Pharma licensed a system developed in the lab of Gay Crooks at the University of California, Los Angeles, that creates an artificial thymus “organoid” in a dish capable of mass producing the immune system’s T cells from pluripotent stem cells. Just growing stem cells in the lab yields tiny amounts of T cells. They naturally mature in our bodies in the thymus gland, and seem to need that nurturing to thrive.

T-cell based immune therapy is all the rage now in cancer therapy because early trials are producing some pretty amazing results, and Kite is a leader in the field. But up until now those therapies have all been autologous—they used the patient’s own cells and manipulate them individually in the lab. That makes for a very expensive therapy. Kite sees the Crooks technology as a way to turn the procedure into an allogeneic one—using donor cells that could be pre-made for an “off-the-shelf” therapy. Their press release also envisioned adding some genetic manipulation to make the cells less likely to cause immune complications.

FierceBiotech published a bit more analysis of the deal, but we are not going to go into more detail on the actual science now. Crooks is finalizing publication of the work in a scientific journal, and when she does you can get the details here. Stay tuned.

How the Ice Bucket Challenge changed the fight against ALS

Ice Bucket2

200 people in Boston take the Ice Bucket Challenge: Photo courtesy Forbes

A couple of years ago millions of people did something they probably never thought they would: they dumped a bucket of ice cold water on their head to raise awareness about a disease most of them had probably never heard of, and almost certainly knew very little about.

The disease was ALS, also known as Lou Gehrig’s disease, and the Ice Bucket Challenge was something that went from a fun idea by a supporter of the ALS Association, to a blockbuster $220 million fundraiser. Like any good idea it sparked a backlash with critics accusing it of being a lazy way for people to feel good without actually doing anything, of diverting money from other charities, and even of just wasting water at a time of drought (at least here in California.)

But two years later we can now look back and see if those critics were correct, and if the money raised did make a difference. And the answer, I’m happy to say, is no and yes. In that order.

An article in the New Yorker magazine, by James Surowiecki, takes a look at what has happened since the Ice Bucket Challenge exploded on the scene and it has some good news:

  • Contributions to the ALS Association remain higher than before the Challenge
  • The average age of donors dropped from 50+ to 35
  • The Challenge may have helped spur an increase in overall donations to charity

All this is, of course, excellent news. But there’s an even more important point, which is that the money raised by the Challenge has helped advance ALS research further and faster than ever before.

Barbara Newhouse, the CEO of the ALS Association told Surowiecki:

“The research environment is dramatically different from what it was. We’re seeing research that’s really moving the needle not just on the causes of the disease but also on treatments and therapies.”

As an example Newhouse cites a study, published in Science  last summer, by researchers at Johns Hopkins that helped explain protein clumps found in the brains of people with ALS. Philip Wong, one of the lead authors of the study, says money raised by the Challenge helped make their work possible;

“Without it, we wouldn’t have been able to come out with the studies as quickly as we did. The funding from the ice bucket is just a component of the whole—in part, it facilitated our effort.”

And just this week the ALS Association said funding from the Challenge helped identify a gene connected to the disease.

Having been one of those who took a dunk for science – and we did ours early on, when the Challenge had only raised $4m – it’s nice to know something as silly and simple can have such a profound impact on developing treatments for a deadly disorder.

 

 

Cloning breakthrough: Dolly the sheep has sister clones and they’re healthy

On the topic of famous farm animals, a few come to mind: Babe the pig, Old Yeller, Mr. Ed, and the cast of Charlotte’s Web. Many of us grew up with these fictional characters and hold them near and dear to our heart, but what about real, living farm animals? The first that comes to my mind is Dolly the sheep.

Back in 1996, scientists made a major breakthrough when they cloned a sheep which they named after the famous singer and actress Dolly Parton. This famous sheep was born in a test tube – a product of a scientific process called somatic cell nuclear transfer (SCNT). It involves transferring the nucleus (which contains a cell’s genetic material) from an adult cell – a mammary gland cell in the case of Dolly – into an unfertilized egg cell that has had its own nucleus removed. Much like jumping a car, scientists use an electric shock to trigger the egg cell to divide and develop into an embryo that has the exact genetic makeup as the original organism it was derived from.

Are cloned animals healthy?

SCNT is a very inefficient process with a high failure rate during embryonic and fetal development. Dolly was a huge achievement for scientists as she was the first mammal to be successfully cloned using SCNT. Unfortunately, even though Dolly lived to the age of six and a half years, she wasn’t the healthiest of sheep. She suffered from a severe form of arthritis and tumors in her lungs and was eventually put down to relieve her from pain. Scientists hypothesized that the lung cancer was likely caused by a common virus that infects sheep, but they questioned whether some of Dolly’s other symptoms were caused by accelerated aging resulting from the cloning process.

Whether cloned animals are physically healthy and age normally are questions that have spurred much debate amongst scientists since Dolly’s inception. Further experiments have shown that cloned mammals that survive past their infancy are typically healthy, but some experiments in mice showed that cloned mice tended to be more obese, have diabetic symptoms, and live shorter lives. Concerns about the safety of cloning prompted many countries to ban reproductive cloning in mammals until more was known about the process.

Good news for Dolly’s sisters

Dolly’s 20th anniversary since her birth was earlier this year, and in celebration, many journals and news outlets wrote about the progress of SCNT and cloning over the past two decades. This week, a new study added an exciting new chapter to these recent stories about Dolly.

Published in Nature Communications, scientists from the University of Nottingham in Britain reported that cloned sheep are healthy and live normal lives. They studied 13 cloned sheep, four of which were Dolly’s sisters cloned from the same mammary gland cell line as Dolly. These sheep were between 7-9 years of age which is near the end of a healthy sheep’s average lifespan of 10 years.

Cloned sheep, sisters to the famous Dolly the Sheep. (University of Nottingham)

Cloned sheep, sisters to the famous Dolly the Sheep. (University of Nottingham)

The scientists wanted to know whether cloning had any negative impact on the health and lifespan of these sheep. Lead author on the study, Dr. Kevin Sinclair, explained to the Washington Post:

“When we did the study, these clones were already 2½ years older than Dolly was when she died. And they appeared to be perfectly healthy, but we wanted to see if they might be harboring subtle defects.”

They conducted studies that assessed symptoms typically caused by aging in both humans and sheep. These included tests for blood pressure, insulin sensitivity, arthritis, and heart disease. They also conducted MRI scans and X-rays to look at the integrity of their bones, joints, and muscles.

On the whole, the sheep were healthy and their tests yielded normal results. A few of the cloned sheep had early signs of arthritis, but their conditions were similar to normal non-cloned sheep of the same age. The scientists concluded that there were no obvious signs of premature aging in this group of cloned sheep and that the cloning process did not have negative effects on the health and lifespan of these animals.

“It was quite obvious that the concerns of Dolly just didn’t relate,” Sinclair said. “So you can’t extend beyond the Dolly experience and say this premature aging applies to all clones.”

Cloning breakthrough but questions remain about safety

This study, which many scientists are considering as a “breakthrough in cloning”, has received a lot of attention in the media from major news outlets like the New York Times, Washington Post, Statnews, and NPR.

The New York Times piece does a great job of discussing how the advancements in cloning could have positive impacts on reproductive technology, the farming industry (raising cloned farm animals as a food source), therapeutic development, and saving endangered species. But the article also balances this optimism with caution over the safety and ethics behind reproductive cloning. They posed the cloning safety question to Dr. Sinclair, the lead author on the study, whose response was positive but referenced the remaining issue of cloning being an inefficient process:

“If they [cloned sheep] could speak, they would say ‘yes; it’s perfectly safe. They’re perfectly healthy, and they’re old ladies now, and for them, their whole process worked perfectly. But there are others who struggled to adapt after birth.”

The STATNews piece also made a good point that further scientific studies on the cloned sheep need to be done to test for molecular signs of aging such as shortened telomeres, before the scientists can truly claim that these sheep are living normal healthy lives. The cloned sheep probably will live for another year at which point the scientists said they will conduct further experiments to look for other signs of aging at the cellular level.

Embryonic gene reverses old age in adult stem cells, in the lab

Getting old is an inevitable fact of life but what exactly causes it? One major hallmark of the aging process is cell senescence, in which cells gradually lose the ability to divide, leading to a breakdown in proper organ function. Adult stem cells that reside in our tissues usually spring into action to replenish cells lost to senescence (as well as injury and disease). But, unfortunately, senescence also affects stem cells, causing their natural regenerative capacity to diminish as we age.

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During the aging process, our stem cells gradually lose their regenerative potential (image source)

But what if we could tinker with senescence in these elderly stem cells? Could we slow down the aging process? A recent study by University of Buffalo scientists says yes, at least in a petri dish. Reporting in Stem Cells, the team shows that artificially activating the NANOG gene alone can reverse aging in adult mesenchymal stem cells (MSCs) and restore their full potential to form functional muscle tissue.

If you’re up on your induced pluripotent stem (iPS) cell knowledge, then you probably know that NANOG is a member of the “famous four”: the group of genes that can reprogram, say, a skin or blood cell, back into an embryonic stem cell-like state.  In this study, the research team derived human MSCs and mimicked senescence by allowing the cells to divide 12 to 16 times (Late Passage, or LP) in petri dishes and compared them to cells allowed to divide only a few times (Early Passage, or EP). The cells were genetically engineered to produce high levels of NANOG when the drug tetracycline was added to the cell culture.

First, the team looked at the impact of NANOG activation on various genes. They found that the activation level of several genes that had been suppressed in the senescent LP cells was restored to the levels seen in the pre-senescent EP cells. A closer look at the identity of those genes showed they were genes important for the capacity of a cell to develop into muscle and blood vessel which corresponds well with the MSCs potential to specialize into muscle and vascular tissue. Based on that genetic analysis, follow up experiments showed that NANOG indeed restored the senescent LP cells’ potential to develop into muscle and restore the muscle tissue’s contractile function.

Premature senescence is observed in diseases such as Hutchinson–Gilford Progeria Syndrome (HGPS), a fatal genetic disorder that causes rapid aging in childhood. NANOG was artificially activated in human MSCs, derived from a HGPS patient in this study, and also showed a restoration of the MSCs’ potential, as seen in the other donor cells.

In a university press release, lead author Stelios Andreadis, summarized the findings this way:

“Our research into Nanog is helping us to better understand the process of aging and ultimately how to reverse it.”

 

This work is very early days for this research especially given that these studies were performed in lab dishes and not animals. And because NANOG is a powerful gene that promotes embryonic and stem cell identity, the scientists will need to look into potential negative long term side effects for activating NANOG in adult stem cells. Ultimately, this path of research could uncover methods to treat aging-related diseases.

Out of the mouths, or in this case hearts, of babes comes a hopeful therapy for heart attack patients

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Lessons learned from babies with heart failure could now help adults

Inspiration can sometimes come from the most unexpected of places. For English researcher Stephen Westaby it came from seeing babies who had heart attacks bounce back and recover. It led Westaby to a new line of research that could offer hope to people who have had a heart attack.

Westaby, a researcher at the John Radcliffe hospital in Oxford, England, found that implanting a novel kind of stem cell in the hearts of people undergoing surgery following a heart attack had a surprisingly significant impact on their recovery.

Westaby got his inspiration from studies showing babies who had a heart attack and experienced scarring on their heart, were able to bounce back and, by the time they reached adolescence, had no scarring. He wondered if it was because the babies’ own heart stem cells were able to repair the damage.

Scarring is a common side effect of a heart attack and affects the ability of the heart to be able to pump blood efficiently around the body. As a result of that diminished pumping ability people have less energy, and are at increased risk of further heart problems. For years it was believed this scarring was irreversible. This study, published in the Journal of Cardiovascular Translational Research, suggests it may not be.

Westaby and his team implanted what they describe as a “novel mesenchymal precursor (iMP)” type of stem cell in the hearts of patients who were undergoing heart bypass surgery following a heart attack. The cells were placed in parts of the heart that showed sizeable scarring and poor blood flow.

Two years later the patients showed a 30 percent improvement in heart function, a 40 percent reduction in scar size, and a 70 percent improvement in quality of life.

In an interview with the UK Guardian newspaper, Westaby admitted he was not expecting such a clear cut benefit:

“Quite frankly it was a big surprise to find the area of scar in the damaged heart got smaller,”

Of course it has to be noted that the trial was small, only involving 11 patients. Nonetheless the findings are important and impressive. Westaby and his team now hope to do a much larger study.

CIRM is funding a clinical trial with Capricor that is taking a similar approach, using stem cells to rejuvenate the hearts of patients who have had heart attacks.

Fred Lesikar, one of the patient’s in the first phase of that trial, experienced a similar benefit to those in the English trial and told us about it in our Stories of Hope.