Stem cell stories that caught our eye: designer socks for cancer patients, stem-cell derived stomachs and fighting off bone infections

Inspiring cancer patients with designer socks. (Karen Ring)
Here’s a motivating story we found in the news this week about a cancer survivor who’s bringing inspiration to other cancer patients with designer socks. Yes, you read that correctly, socks.

Jake Teitelbaum is a student at Wake Forest University and suffers from a rare form of blood cancer called Refractory Hodgkin’s lymphoma. Since his diagnosis, Jake has been admitted to hospitals multiple times. Each time he received a welcome package of a gown and a pair of beige, “lifeless” socks. After his fifth welcome package, this time to receive a life-saving stem cell treatment, Jake had had enough of the socks.

He explained in a story by USA Today College,

“[Those socks] represented chemotherapy and being in isolation. They were the embodiment of that experience.”

Jake ditched the hospital socks and started bringing his own to prove that his cancer didn’t define him. Even though his cancer kept coming back, Jake wanted to prove he was just as resilient.

Jake Teitelbaum

Jake Teitelbaum

Feeling liberated and in control, Jake decided to share his socks with other patients by starting the Resilience Project. Patients can go to the Resilience website and design their own socks that represent their experiences with cancer. The Resilience project also raises money for cancer patients and their families.

“We provide tangible benefits and create fun socks, but what we’re doing comes back to the essence of resilience,” said Jake. “These terrible circumstances where we’re at our most vulnerable also give us the unique opportunity to grow.”

Jake was declared cancer free in October of 2016. You can learn more about the Resilience project on their website and by watching Jake’s video below.

 

Feeding disease knowledge with stem cell-derived stomach cells.
Using educated guess work and plenty of trial and error in the lab, researchers around the world have successfully generated many human tissues from stem cells, including heart muscle cells, insulin-producing cells and nerve cells to name just a few. Reporting this week in Nature, stem cell scientists at Cincinnati’s Children Hospital have a new cell type under their belt. Or maybe I should say above their belt, because they have devised a method for coaxing stem cells to become stomach mini organs that can be studied in a petri dish.

Confocal microscopic image shows tissue-engineered human stomach tissues from the corpus/fundus region, which produce acid and digestive enzymes. Image: Cincinnati Children’s Hospital Medical Center

Confocal microscopic image shows tissue-engineered human stomach tissues from the corpus/fundus region, which produce acid and digestive enzymes. Image: Cincinnati Children’s Hospital Medical Center

With this method in hand, the team is poised to make new discoveries about how the stomach forms during human development and to better understand stomach diseases. In a press release, team lead Jim Wells pointed out the need to find new therapies for stomach disease:

“Diseases of the stomach impact millions of people in the United States and gastric [stomach] cancer is the third leading cause of cancer-related deaths worldwide.”

The cells they generated are those found in the corpus/fundus area of the stomach which releases enzymes and hydrochloric acid to help us break down and digest the food we eat. The team is particularly interested to use the mini organs to study the impact of H. pylori infection, a type of bacteria that causes ulcers and has been linked to stomach cancers.

In an earlier study, Wells’ group devised stem cell recipes for making cells from an area of the stomach, called the antrum, that produces hormones that affect digestion and appetite. Wells thinks having both tissue types recreated in a petri dish may help provide a complete picture of stomach function:

James Wells

James Wells

“Now that we can grow both antral- and corpus/fundic-type human gastric mini-organs, it’s possible to study how these human gastric tissues interact physiologically, respond differently to infection, injury and react to pharmacologic treatments.”

 

 

A silver bullet for antibiotic-resistant bone infections?
Alexander Fleming’s discover of penicillin in the 1920’s marked the dawn of antibiotics – drugs which kill off bacteria and help stop infections. Rough estimates suggest that over 200 million lives have been saved by these wonder drugs. But over time there’s been a frightening rise in bacteria that are resistant to almost all available antibiotics.

These super resistant “bugs” are particularly scary for people with chronic bone infections because the intense, long term antibiotic medication required to keep the infection in check isn’t effective. But based on research published this week in Tissue Engineering, the use of stem cells and silver may provide a new treatment option.

Scanning Electron micrograph of methicillin-resistant Staphylococcus aureus (MRSA, brown spheres) surrounded by cellular debris. MRSA, the bacteria examined in this study, is resistant by many antibiotics

Scanning Electron micrograph of methicillin-resistant Staphylococcus aureus (MRSA, brown spheres) surrounded by cellular debris. MRSA, the bacteria examined in this study, is resistant by many antibiotics. (Wikimedia)

It’s been known for many years that silver in liquid form can kill bacteria and scientists have examined ways to deliver a controlled release of silver nanoparticles at the site of the bone infection. But there has been a lot of concern, including by the Food and Drug Administration (FDA), about the toxicity of silver nanoparticles to human cells.

In this study, a team led by Elizabeth Loboa from the University of Missouri instead looked at the use of silver ions which are safer than the nanoparticles. The team developed a three-dimensional cell culture system that resembles bone by growing human bone-forming stem cells on a tissue engineered scaffold, which also slowly releases silver ions.

The researchers stimulated the stem cells within the scaffold to specialize into bone cells and included a strain of bacteria that’s resistant to multiple antibiotics. They found that the silver ions effectively killed the bacteria and at the same time did not block the bone-forming stem cells. If this work holds up, doctors may one day use this silver ion-releasing, biodegradable scaffold to directly treat the area of bone infection. And to help prevent infection after joint replacement procedures, surgeons may rely on implants that are coated with these scaffolds.

Your Guide to Awesome Stem Cell Conferences in 2017

Welcome to 2017, a year that will likely be full of change and new surprises. I’m hoping that some of these surprises will be in regenerative medicine with new stem cell therapies showing promise or effectiveness in clinical trials.

A great way to stay on top of new advances in stem cell research is to attend scientific conferences and meetings. Some of them are well known and highly attended like the International Society for Stem Cell Research (ISSCR) conference, which this year will be in Boston in June. There are also a few smaller, more intimate conferences focusing on specific topics from discovery research to clinical therapies.

There are loads of stem cell meetings this year, but a few that I would like to highlight. Here’s my abbreviated stem cell research conference and meeting guide for 2017. Some are heavy duty research-focused events and probably not suitable for someone without a science background; they’re also expensive to sign up for. I’ve marked those with an * asterix.


January 8-12th, Keystone Symposium (Fee to register)*

Keystone will be hosting two concurrent stem cell meetings in Tahoe next week, which are geared for researchers in the field. One will be on neurogenesis during development and in the adult brain and the other will be on transcriptional and epigenetic control in stem cells. CIRM is one of the co-funders of this meeting and will be hosting a panel focused on translating basic research into clinical trials. Keystone symposiums are small, intimate meetings rich with scientific content and great for networking. Be on the look out for blog coverage about this meeting in the coming weeks.


February 3rd, Stanford Center for Definitive and Curative Medicine Symposium (Free to the public)

This free symposium at Stanford University in Palo Alto, CA will present first-in-human cell and gene therapies for a number of disorders including bone marrow, skin, cardiac, neural, uterine, pancreatic and neoplastic disorders. Speakers include scientists, translational biologists and clinicians. Irv Weissman, a Stanford professor and CIRM grantee focused on translational cancer research, will be the keynote speaker. Space is limited so sign up ASAP!


March 23rd, CIRM Alpha Stem Cell Clinics Symposium (Free to the public)

This free one-day meeting will bring together scientists, clinicians, patient advocates, and other partners to describe how the CIRM Alpha Stem Cell Clinics Network is making stem cell therapies a reality for patients. The City of Hope Alpha Clinic is part of a statewide effort funded by CIRM to develop a network of “Alpha Clinics” that has one unifying goal: to accelerate the development and delivery of stem cell treatments to patients.

City of Hope Medical Center and Alpha Stem Cell Clinic

City of Hope Medical Center and Alpha Stem Cell Clinic


June 14-17th, International Society for Stem Cell Research (Fee to register)*

The Annual ISSCR stem cell research conference will be hosted in Boston this year. This is an international conference focusing on new developments in stem cell science and technology. CIRM was one of the funders of the conference last year when ISSCR was in San Francisco. It’s one of my favorite research events to attend full of interesting scientific presentations and great for meeting future collaborators.


For a more comprehensive 2017 stem cell conference and meeting guide, check out Paul Knoepfler’s Niche blog.

Genetically engineered immune cells melt away deadly brain tumors

MRI scan of patient with glioblastoma tumor. (wikicommons)

MRI scan of patient with glioblastoma. (wikicommons)

Cancers come in many different forms. Some are treatable if caught early and other aren’t. One of the most deadly types of cancers are glioblastomas – a particularly aggressive form of brain tumor.  Patients diagnosed with glioblastoma have an average life expectancy of 12-15 months and there is no cure or effective treatment that extends life.

While a glioblastoma diagnosis has pretty much been a death sentence, now there could be a silver lining to this deadly, fast-paced disease. Last week, scientists from the City of Hope in southern California reported in the New England Journal of Medicine, a new cell-based therapy that melted away brain tumors in a patient with an advanced stage of glioblastoma.

An Immunotherapy Approach to Glioblastoma

The patient is a 50-year-old man named Richard Grady who was participating in an investigational clinical trial run out of the City of Hope’s CIRM Alpha Stem Cell Clinic. A brain scan revealed a brightly lit tumor on the right side of Richard’s brain. Doctors surgically removed the tumor and treated him with radiation in an attempt to staunch further growth. But after six months, the tumors came back with a vengeance, spreading to other parts of his brain, lighting up his MRI scan like a Christmas tree.

With few treatment options and little time left, Richard was enrolled in the City of Hope trial that was testing a cell-based immunotherapy that recognizes and attacks cancer cells. It’s called CAR T-cell therapy – a term that you probably have heard in the news as a promising and cutting-edge treatment for cancer. Scientists extract immune cells, called T-cells, from a patient’s blood and reengineer them in the laboratory to recognize unique surface markers on cancer cells. These specialized CAR T-cells are then put back into the patient to attack and kill off cancer cells.

In Richard’s case, CAR-T cells were first infused into his brain through a tube in an area where a tumor was recently removed. No new tumors grew in that location of his brain, but tumors in other areas continued to grow and spread to his spinal cord. At this point, the scientists decided to place a second tube into a cavity of the brain called the ventricles, which contain a clear liquid called cerebrospinal fluid. Directly infusing into the spinal fluid allowed the cancer fighting cells to travel to different parts of the brain and spinal cord to attack the tumors.

Behnam Badie, senior author on the study and neurosurgery chief at the City of Hope, explained in a news release,

Benham Badie, City of Hope

Benham Badie, City of Hope

“By injecting the reengineered CAR-T cells directly into the tumor site and the ventricles, where the spinal fluid is made, the treatment could be delivered throughout the patient’s brain and also to the spinal cord, where this particular patient had a large metastatic tumor.”

 

Bye Bye Brain Tumors? Almost…

Three infusions of the CAR T-cell treatment shrunk Richard’s tumors noticeably, and a total of ten infusions was enough to melt away Richard’s tumors completely. Amazingly, Richard was able to reduce his medications and go back to work.

TESt

CAR T-cell therapy reduces brain tumors when infused into the spinal fluid. (NEJM)

The effects of the immunotherapy lasted for seven-and-a-half months. Unfortunately, his glioblastoma did come back, and he is now undergoing radiation treatment. Instead of being discouraged by these results, we should be encouraged. Patients with advanced cases of glioblastoma like Richard often have only weeks left to live, and the prospect of another seven months of life with family and friends is a gift.

Following these promising results in a single patient, the City of Hope team has now treated a total of nine patients in their clinical trial. Their initial results indicate that the immunotherapy is relatively safe. Further studies will be done to determine whether this therapy will be effective at treating other types of cancers.

CIRM Alpha Clinics Advance Stem Cell Treatments

The findings in this study are particularly exciting to CIRM, not only because they offer a new treatment option for a deadly brain cancer, but also because the clinical trial testing this treatment is housed at one of our own Alpha Clinics. In 2014, CIRM funded three stem cell-focused clinics at the City of Hope, UC San Diego, and a joint clinic between UC Los Angeles and UC Irvine. These clinics are specialized to support high quality trials focused on stem cell treatments for various diseases. The CIRM team will be bringing a new Alpha Clinics concept plan to its governing Board for approval in February.

Geoff Lomax, Senior Officer of Strategic Infrastructure at CIRM who oversees the CIRM Alpha Clinics, commented on the importance of City of Hope’s glioblastoma trial,

“Treating this form of brain cancer is one of the most vexing challenges in medicine. With the support and expertise of the CIRM Alpha Stem Cell Clinic, City of Hope is harnessing the power of patients’ immune cells to treat this deadly disease.”

Neil Littman, CIRM Director of Business Development and Strategic Infrastructure added,

“This study provides important proof-of-concept that CAR-T cells can be used to target hard-to-treat solid tumors and is precisely the type of trial the CIRM Alpha Stem Cell Clinic Network is designed to support.”

For more details on this study, watch the video below from City of Hope:

Cured by Stem Cells

cirm-2016-annual-report-web-12

To get anywhere you need a good map, and you need to check it constantly to make sure you are still on the right path and haven’t strayed off course. A year ago the CIRM Board gave us a map, a Strategic Plan, that laid out our course for the next five years. Our Annual Report for 2016, now online, is our way of checking that we are still on the right path.

I think, without wishing to boast, that it’s safe to say not only are we on target, but we might even be a little bit ahead of schedule.

The Annual Report is chock full of facts and figures but at the heart of it are the stories of the people who are the focus of all that we do, the patients. We profile six patients and one patient advocate, each of whom has an extraordinary story to tell, and each of whom exemplifies the importance of the work we support.

brenden_stories_of_hope

Brenden Whittaker: Cured

Two stand out for one simple reason, they were both cured of life-threatening conditions. Now, cured is not a word we use lightly. The stem cell field has been rife with hyperbole over the years so we are always very cautious in the way we talk about the impact of treatments. But in these two cases there is no need to hold back: Evangelina Padilla Vaccaro and Brenden Whittaker have been cured.

evangelina

Evangelina: Cured

 

In the coming weeks we’ll feature our conversations with all those profiled in the Annual Report, giving you a better idea of the impact the stem cell treatments have had on their lives and the lives of their family. But today we just wanted to give a broad overview of the Annual Report.

The Strategic Plan was very specific in the goals it laid out for us. As an agency we had six big goals, but each Team within the agency, and each individual within those teams had their own goals. They were our own mini-maps if you like, to help us keep track of where we were individually, knowing that every time an individual met a goal they helped the Team get closer to meeting its goals.

As you read through the report you’ll see we did a pretty good job of meeting our targets. In fact, we missed only one and we’re hoping to make up for that early in 2017.

But good as 2016 was, we know that to truly fulfill our mission of accelerating treatments to patients with unmet medical needs we are going to have do equally well, if not even better, in 2017.

That work starts today.

 

The 10 Most Popular Stem Cellar Stories of 2016

Happy Holidays to our loyal Stem Cellar fans! 🎉

The days between Christmas and New Years are my favorite time of the year. The roads are empty, parking is plentiful and no one is in the office to judge my voracious cookie consumption. It’s also a time for us to reflect on what we’ve accomplished in 2016 at CIRM and to revisit the most interesting stories that we’ve blogged about on the Stem Cellar.

We will be publishing our Annual Report on January 2nd, so be sure to check out our blog then for an update on what CIRM has been up to this past year. The report is chock full of inspiring stories about the stem cell research we’re funding, the scientists behind the research, and the brave patients who volunteered to test these stem cell treatments in clinical trials.

As a prelude to our Annual Report, I bring you the Top 10 Most Popular Stem Cellar Blogs of 2016 (in order). These include blogs about CIRM-funded research and our clinical trials as well as other really cool stem cell stories that you may have even read about in the news. Enjoy and see you in the New Year!

stem-cellar-stories

  1. New Stem Cell Treatment for ALS May Slow Disease Progression
  2. Young Man With Spinal Cord Injury Regains Use of Hands and Arms After Stem Cell Therapy
  3. Desperate Patients and False Hope: A Troubling Trend for Stem Cell-Based Therapies
  4. A Win for Diabetes: Scientists Make Functional Pancreatic Cells From Skin
  5. Stem Cell Transplant Offers Jake a Glimpse of Hope
  6. Why is a Cell Therapy that Restores Sight to the Blind Against the Law?
  7. Stem cell stories that caught our eye: heart muscle-on-a-chip, your own private microliver, the bloody holy grail and selfish sperm
  8. A New Way to Make Heart Stem Cells Could Potentially Repair Damage of Heart Disease
  9. CIRM-Funded Stem Cell Clinical Trial for Retinitis Pigmentosa Focuses on Next Stage
  10. Patients beware: Warnings About Shady Clinics and Suspect Treatments

Bonus 2016 blogs (A few of my favorites that didn’t quite make the top ten, but I thought were pretty rad):

 

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Stem cell heroes: patients who had life-saving, life-changing treatments inspire CIRM Board

 

It’s not an easy thing to bring an entire Board of Directors to tears, but four extraordinary people and their families managed to do just that at the last CIRM Board meeting of 2016.

The four are patients who have undergone life-saving or life-changing stem cell therapies that were funded by our agency. The patients and their families shared their stories with the Board as part of CIRM President & CEO Randy Mill’s preview of our Annual Report, a look back at our achievements over the last year.

The four included:

jake_javier_stories_of_hope

Jake Javier, whose life changed in a heartbeat the day before he graduated high school, when he dove into a swimming pool and suffered a spinal cord injury that left him paralyzed from the chest down. A stem cell transplant is giving him hope he may regain the use of his arms and hands.

 

 

karl

Karl Trede who had just recovered from one life-threatening disease when he was diagnosed with lung cancer, and became the first person ever treated with a new anti-tumor therapy that helped hold the disease at bay.

 

brenden_stories_of_hopeBrenden Whittaker, born with a rare immune disorder that left his body unable to fight off bacterial or fungal infections. Repeated infections cost Brenden part of his lung and liver and almost killed him. A stem cell treatment that gave him a healthy immune system cured him.

 

 

evangelinaEvangelina Padilla Vaccaro was born with severe combined immunodeficiency (SCID), also known as “bubbly baby” disease, which left her unable to fight off infections. Her future looked grim until she got a stem cell transplant that gave her a new blood system and a healthy immune system. Today, she is cured.

 

 

Normally CIRM Board meetings are filled with important, albeit often dry, matters such as approving new intellectual property regulations or a new research concept plan. But it’s one thing to vote to approve a clinical trial, and a very different thing to see the people whose lives you have helped change by funding that trial.

You cannot help but be deeply moved when you hear a mother share her biggest fear that her daughter would never live long enough to go to kindergarten and is now delighted to see her lead a normal life; or hear a young man who wondered if he would make it to his 24th birthday now planning to go to college to be a doctor

When you know you played a role in making these dreams happen, it’s impossible not to be inspired, and doubly determined to do everything possible to ensure many others like them have a similar chance at life.

You can read more about these four patients in our new Stories of Hope: The CIRM Stem Cell Four feature on the CIRM website. Additionally, here is a video of those four extraordinary people and their families telling their stories:

We will have more extraordinary stories to share with you when we publish our Annual Report on January 1st. 2016 was a big year for CIRM. We are determined to make 2017 even bigger.

Using stem cells to fix bad behavior in the brain

 

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Gladstone Institutes Steven Finkbeiner and Gaia Skibinski: Photo courtesy Chris Goodfellow, Gladstone Institutes

Diseases of the brain have many different names, from Alzheimer’s and Parkinson’s to ALS and Huntington’s, but they often have similar causes. Researchers at the Gladstone Institutes in San Francisco are using that knowledge to try and find an approach that might be effective against all of these diseases. In a new CIRM-funded study, they have identified one protein that could help do just that.

Many neurodegenerative diseases are caused by faulty proteins, which start to pile up and cause damage to neurons, the brain cells that are responsible for processing and transmitting information. Ultimately, the misbehaving proteins cause those cells to die.

The researchers at the Gladstone found a way to counter this destructive process by using a protein called Nrf2. They used neurons from humans (made from induced pluripotent stem cells – iPSCs – hence the stem cell connection here) and rats. They then tested these cells in neurons that were engineered to have two different kinds of mutations found in  Parkinson’s disease (PD) plus the Nrf2 protein.

Using a unique microscope they designed especially for this study, they were able to track those transplanted neurons and monitor what happened to them over the course of a week.

The neurons that expressed Nrf2 were able to render one of those PD-causing proteins harmless, and remove the other two mutant proteins from the brain cells.

In a news release to accompany the study in The Proceedings of the National Academy of Sciences, first author Gaia Skibinski, said Nrf2 acts like a house-cleaner brought in to tidy up a mess:

“Nrf2 coordinates a whole program of gene expression, but we didn’t know how important it was for regulating protein levels until now. Over-expressing Nrf2 in cellular models of Parkinson’s disease resulted in a huge effect. In fact, it protects cells against the disease better than anything else we’ve found.”

Steven Finkbeiner, the senior author on the study and a Gladstone professor, said this model doesn’t just hold out hope for treating Parkinson’s disease but for treating a number of other neurodegenerative problems:

“I am very enthusiastic about this strategy for treating neurodegenerative diseases. We’ve tested Nrf2 in models of Huntington’s disease, Parkinson’s disease, and ALS, and it is the most protective thing we’ve ever found. Based on the magnitude and the breadth of the effect, we really want to understand Nrf2 and its role in protein regulation better.”

The next step is to use this deeper understanding to identify other proteins that interact with Nrf2, and potentially find ways to harness that knowledge for new therapies for neurodegenerative disorders.

Pregnant women’s stem cells could help battle brittle bone diseases like osteoporosis

pregnant

Sometimes I wonder how a scientist ever came up with an idea for a potential treatment. Case in point is a study in the journal Scientific Reports, where researchers use stem cells from the amniotic fluid of a pregnant woman to cure osteoporosis in mice! What researcher, seeing a pregnant woman, thought to her or himself “I wonder if…..”

Regardless of how they came up with the idea, we might be glad they did because this study showed that those stem cells could reduce the number of fractures in mice with brittle bone disease by 78 percent. And that’s raising hopes they might one day be able to do the same for people.

Researchers at University College London took mesenchymal stem cells (MSCs) that had been shed by babies into the amniotic fluid of their mother, and injected them into mice with brittle bone disease. Previous studies had suggested that MSCs, taken at such an early age, might be more potent than similar cells taken from adults. That certainly seems to have been the case here where the treated mice had far fewer fractures than untreated mice.

Pascale Guillot, the lead researcher of the study, told the Guardian newspaper:

“The stem cells we’ve used are excellent at protecting bones. The bones become much stronger and the way the bone is organised internally is of much higher quality.”

 

What was also interesting was not just what they did but how they did it. You might think that the injected stem cells helped reduce fractures by forming new bones. You might think that, but you’d be wrong. Instead, the stem cells seem to have worked by releasing growth factors that stimulated the mouse’s own bone cells to kick into a higher gear, and help build stronger bones.

In the study the researchers say using MSCs from amniotic fluid has a number of distinct advantages over using MSCs from adults:

  • They are easier to expand into large numbers needed for therapies
  • They don’t create tumors
  • The body’s immune system won’t attack them
  • They are smaller and so can move around with greater ease
  • They are easier to reprogram into different kinds of cells

Next Guillot and his team want to explore if this approach could be used to treat children and adults with brittle bone disease, and to help adults with osteoporosis, a problem that affects around 44 million people in the US.

 “The discovery could have a profound effect on the lives of patients who have fragile bones and could stop a large number of their painful fractures.”

Stem cell-derived pacemaker cells could help weak hearts keep the beat

In an average lifetime, the human heart dutifully beats more than 2.5 billion times. You can thank an area of the heart called the sinoatrial node, or SAN, which acts as the heart’s natural pacemaker. The SAN is made up of specialized heart muscle cells that, like a conductor leading an orchestra, dictates the rate which all other heart muscle cells will follow. But instead of a conductor’s baton, the cells of the SAN send out an electrical signal which stimulates the heart muscle cells to beat in unison.

Stem cell-derived pacemaker cells (blob in center) stimulate the layer of heart muscle cells  underneath to beat in unison (video: McEwen Centre for Regenerative Medicine).

Artificial pacemakers: an imperfect remedy for irregular heart beats
Certain inherited mutations as well as the aging process can foul up this natural pacemaker signal which usually results in slower, erratic heart rates and leads to poor blood circulation. The current remedy for irregular heart rhythm in these cases is the implantation of an artificial electronic pacemaker into the body. But these devices have their drawbacks: they can’t respond to hormone signals received by the heart, the implantation itself carries a risk of infection and the pacemaker’s battery life is limited to about 7 years so replacement surgeries are needed. Also, for children needing artificial pacemakers, there’s no effective way to adjust the device to adapt to a child’s growing heart.

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X-Ray of implanted electronic pacemaker (Image: Wikipedia)

Now, a Canadian research team at the McEwen Centre for Regenerative Medicine in Toronto aims to create a pacemaker from stem cells to one day provide a biological alternative to current electronic options. In their Nature Biotechnology report published last week, the team describes how they used their expertise in the developmental biology of the heart to successfully devise a method for transforming human embryonic stem cells into functioning pacemaker cells.

If you’ve been following the stem cell field for a while, you’ve probably watched lots of cool videos and read countless stories about beating heart cells grown from stem cells. Then what’s so special about this report? It’s true, you can readily make beating heart muscle cells, or cardiomyocytes, from embryonic stem cells. But usually these methods generate a mixture of various types of cardiomyocytes. The current report instead focused on specifically transforming the stem cells into the SAN pacemaker cells.

Look Ma, no genes inserted!
In 2015, another research team published work showing they had nudged stem cells to become cells with SAN-like pacemaker activity. But that study relied on the permanent insertion of a gene into the cells’ DNA which carries a risk of promoting tumor formation and would not be suitable for clinical use in the future. To generate cells that more closely correspond to the natural pacemaker found in healthy individuals, the researchers in this study created their cells by relying on a gene insertion-free recipe that included the addition of various hormones and growth factors. Stephanie Protze, the first author in the report, explained in a University Health Network press release, the challenge of finding the right ingredients:

“It’s tricky, you have to determine the right signaling molecules, at the right concentration, at the right time to stimulate the stem cells.”

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First author Dr. Stephanize Protze and senior author Gordon Keller, Director of the McEwen Centre
(Photo: McEwen Centre for Regenerative Medicine)

A replacement biological pacemaker: one step closer to reality
Analysis of their method showed that 90% of the human stem cell-derived SAN cells had the correct pacemaker activity. They went on to show that these cells could act as a natural pacemaker both in the petri dish and in rats. These results are an exciting step towards providing a natural pacemaker for people with irregular heartbeat disorders. Still, it’s important to realize that human clinical trials are at least 5 to 10 years down the road because a lot of preclinical animal studies will need to examine safety and effectiveness of such a therapy.

In the meantime, the team is eager to use their new method to grow patient specific pacemaker cells from human induced pluripotent stem cells. This approach will give the researchers a chance to study heart arrhythmia in a petri dish to better understand this health problem and to test drugs that could potentially improve symptoms.

Brain Models Get an Upgrade: 3D Mini-Brains

Every year, companies like Apple, Microsoft and Google work tirelessly to upgrade their computer, software and smartphone technologies to satisfy growing demands for more functionality. Much like these companies, biomedical scientists work tirelessly to improve the research techniques and models they use to understand and treat human disease.

Today, I’ll be talking about a cool stem cell technology that is an upgrade of current models of neurological diseases. It involves growing stem cells in a 3D environment and turning them into miniature organs called organoids that have similar structures and functions compared to real organs. Scientists have developed techniques to create organoids for many different parts of the body including the brain, gut, lungs and kidneys. These tiny 3D models are useful for understanding how organs are formed and how viruses or genetic mutations can affect their development and ability to function.

Brain Models Get an Upgrade

Organoids are especially useful for modeling complex neurological diseases where current animal and 2D cell-based models lack the ability to fully represent the cause, nature and symptoms of a disease. The first cerebral, or brain, organoids were generated in 2013 by Dr. Madeline Lancaster in Austria. These “mini-brains” contained nerve cells and structures found in the cortex, the outermost layer of the human brain.

Since their inception, mini-brains have been studied to understand brain development, test new drugs and dissect diseases like microcephaly – a disease that causes abnormal brain development and is characterized by very small skulls. Mini-brains are still a new technology, and the question of whether these organoids are representative of real human brains in their anatomy and behavior has remained unanswered until now.

Published today in Cell Reports, scientists from the Salk Institute reported that mini-brains are more like human brains compared to 2D cell-based models where brain cells are grown in a single layer on a petri dish. To generate mini-brains, they collaborated with a European team that included the Lancaster lab. They grew human embryonic stem cells in a 3D environment with a cocktail of chemicals that prompted them to develop into brain tissue over a two-month period.

Cross-section of a mini-brain. (Madeline Lancaster/MRC-LMB)

Cross-section of a mini-brain. (Madeline Lancaster/MRC-LMB)

After generating the mini-brains, the next step was to prove that these organoids were an upgrade for modeling brain development. The teams found that the cells and structures formed in the mini-brains were more like human brain tissue at the same stage of early brain development than the 2D models.

Dr. Juergen Knoblich, co-senior author of the new paper and head of the European lab explained in a Salk News Release, “Our work demonstrates the remarkable degree to which human brain development can be recapitulated in a dish in cerebral organoids.”

Are Mini-Brains the Real Thing?

The next question the teams asked was whether mini-brains had similar functions and behaviors to real brains. To answer that question, the scientists turned to epigenetics. This is a fancy word for the study of chemical modifications that influence gene expression without altering the DNA sequence in your genome. The epigenome can be thought of as a set of chemical tags that help coordinate which genes are turned on and which are turned off in a cell. Epigenetics plays important roles in human development and in causing certain diseases.

The Salk team studied the epigenomes of cells in the mini-brains to see whether their patterns were similar to cells found in human brain tissue. Interestingly, they found that the epigenetic patterns in the 3D mini-brains were not like those of real brain tissue at the same developmental stage. Instead they shared a commonality with the 2D brain models and had random epigenetic patterns. While the reason for these results is still unknown, the authors explained that it is common for cells and tissues grown in a lab dish to have these differences.

In a Salk news release, senior author and Salk professor Dr. Joseph Ecker said that even though the current mini-brain models aren’t perfect yet, scientists can still gather valuable information from them in the meantime.

“Our findings show that cerebral organoids as a 3D model of brain function are getting closer to a real brain than 2D models, so perhaps by using the epigenetic pattern as a gauge we can get even closer.”

And while the world eagerly waits for the next release of the iPhone 7, neuroscientists will be eagerly waiting for a new and improved version of mini-brains. Hopefully the next upgrade will produce organoids that behave more like the real thing and can model complex neurological diseases, such as Alzheimer’s, where so many questions remain unanswered.