Gene-editing Technique in Mice Shows Promise for Genetic Disorder in Utero

 

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New research presents a promising new avenue for research into treating genetic conditions during fetal development.
Credit: © llhedgehogll / Fotolia

Each year roughly 16 million parents receive the heartbreaking news that their child is likely to be born with a severe genetic disorder or birth defect. And while these genetic conditions can often be detected during pregnancy, using amniocentesis, there haven’t been any treatment options to correct these genetic conditions before birth. Well – thanks to a group of researchers at Carnegie Mellon University and Yale University that could one day change and offer alternative treatment options for children with genetic disorders while they are still in the womb.

For the first time ever, according to a Carnegie Melon press release, scientists used a gene editing technique to successfully cure a genetic condition in a mouse in utero. Their findings, published in Nature Communications, not only present a promising new avenue for research into treating genetic conditions, but they also open the doors for additional treatment options in the future.

In this study, the researchers used a synthetic molecule called a peptide nucleic acid (PNA) as the basis for a gene editing technique. They had previously used this method to cure beta-thalassemia, a genetic blood disorder that results in the reduced production of hemoglobin, in adult mice. Their technique uses an FDA-approved nanoparticle to deliver PNA molecules, paired with donor DNA, to the site of a genetic mutation. When the PNA-DNA complex identifies a designated mutation, the PNA molecule binds to the DNA and unzips its two strands. The donor DNA then binds with the faulty DNA and spurs the cell’s DNA repair pathways into action, correcting the error.

The researchers believe that their technique might even be able to achieve higher success rates if they can administer it multiple times during gestation. They also hope to see if their technique can be applied to other conditions.

While this research is promising there is a long way to go before the team will be ready to test it in people. However, one CIRM-supported project has already reached that milestone. Dr. Tippi MacKenzie and her team at UCSF are using in utero blood stem cell transplants from the mother to the fetus to help treat alpha thalassemia major, a blood disorder that is almost always fatal.

We recently blogged about this research and how it helped one couple deliver a healthy baby.

https://blog.cirm.ca.gov/2018/06/04/cirm-funded-study-results-in-the-first-ever-in-utero-stem-cell-transplant-to-treat-alpha-thalassemia/

 

 

Coming up with a stem cell FIX for a life-threatening blood disorder

Hemophilia

A promising new treatment option for hemophiliacs is in the works at the Salk Institute for Biological Sciences. Patients with Hemophilia B experience uncontrolled, and sometimes life threatening, bleeding due to loss or improper function of Factor IX (FIX), a protein involved in blood clotting. There is no cure for the disease and patients rely on routine infusions of FIX to prevent excessive blood loss. As you can imagine, this treatment regimen is both time consuming and expensive, while also becoming less effective over time.

Salk researchers, partially funded by CIRM, aimed to develop a more long-term solution for this devastating disease by using the body’s own cells to fix the problem.

In the study, published in the journal Cell Reports, They harvested blood cells from hemophiliacs and turned them into iPSCs (induced pluripotent stem cells), which are able to turn into any cell type. Using gene editing, they repaired the iPSCs so they could produce FIX and then turned the iPSCs into liver cells, the cell type that naturally produces FIX in healthy individuals.

One step therapy

To test whether these FIX-producing liver cells were able to reduce excess blood loss, the scientists injected the repaired human cells into a hemophiliac mouse. The results were very encouraging; they saw a greater than two-fold increase in clotting efficiency in the mice, reaching about a quarter of normal activity. This is particularly promising because other studies showed that increasing FIX activity to this level in hemophiliac humans significantly reduces bleeding rates. On top of that they also observed that these cells were able to survive and produce FIX for up to a year in the mice.

In a news release Suvasini Ramaswamy, the first author of the paper, said this method could eliminate the need for multiple treatments, as well as avoiding the immunosuppressive therapy that would be required for a whole liver transplant.

“The appeal of a cell-based approach is that you minimize the number of treatments that a patient needs. Rather than constant injections, you can do this in one shot.”

While these results provide an exciting new avenue in hemophilia treatment, there is still much more work that needs to be done before this type of treatment can be used in humans. This approach, however, is particularly exciting because it provides an important proof of principle that combining stem cell reprogramming with genetic engineering can lead to life-changing breakthroughs for treating genetic diseases that are not currently curable.

 

 

Stem Cell Roundup: New understanding of Huntington’s; how stem cells can double your DNA; and using “the Gary Oldman of cell types” to reverse aging

This week’s roundup highlights how we are constantly finding out new and exciting ways that stem cells could help change the way we treat disease.

Our Cool Stem Cell Image of the Week comes from our first story, about unlocking some of the secrets of Huntington’s disease. It comes from the Laboratory of Stem Cell Biology and Molecular Embryology at The Rockefeller University

Huntington's neurons

A new approach to studying and developing therapies for Huntington’s disease

Researchers at Rockefeller University report new findings that may upend the way scientists study and ultimately develop therapies for Huntington’s disease, a devastating, inherited neurodegenerative disorder that has no cure. Though mouse models of the disease are well-established, the team wanted to focus on human biology since our brains are more complex than those of mice. So, they used CRISPR gene editing technology in human embryonic stem cells to introduce the genetic mutations that cause HD.

Though symptoms typically do not appear until adulthood, the researchers were surprised to find that in their human cell-based model of HD, abnormalities in nerve cells occur at the earliest steps in brain development. These results suggest that HD therapies should focus on treatments much earlier in life.

The researchers observed another unexpected twist: cells that lack Huntingtin, the gene responsible for HD, are very similar to cells found in HD. This suggests that too little Huntingtin may be causing the disease. Up until now, the prevailing idea has been that Huntington’s symptoms are caused by the toxicity of too much mutant Huntingtin activity.

We’ll certainly be keeping an eye on how further studies using this new model affect our understanding of and therapy development for HD.

This study was published in Development and was picked by Science Daily.

How you can double your DNA

dna

As you can imagine we get lots of questions about stem cell research here at CIRM. Last week we got an email asking if a stem cell transplant could alter your DNA? The answer is, under certain circumstances, yes it could.

A fascinating article in the Herald Review explains how this can happen. In a bone marrow transplant bad blood stem cells are killed and replaced with healthy ones from a donor. As those cells multiply, creating a new blood supply, they also carry the DNA for the donor.

But that’s not the only way that people may end up with dual DNA. And the really fascinating part of the article is how this can cause all sorts of legal and criminal problems.

One researcher’s efforts to reverse aging

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Gary Oldman: Photo courtesy Variety

“Stem cells are the Gary Oldman of cell types.” As a fan of Gary Oldman (terrific as Winston Churchill in the movie “Darkest Hour”) that one line made me want to read on in a profile of Stanford University researcher Vittorio Sebastiano.

Sebastiano’s goal is, to say the least, rather ambitious. He wants to reverse aging in people. He believes that if you can induce a person’s stem cells to revert to a younger state, without changing their function, you can effectively turn back the clock.

Sebastiano says if you want to achieve big things you have to think big:

“Yes, the ambition is huge, the potential applications could be dramatic, but that doesn’t mean that we are going to become immortal in some problematic way. After all, one way or the other, we have to die. We will just understand aging in a better way, and develop better drugs, and keep people happier and healthier for a few more years.”

The profile is in the journal Nautilus.

How a tiny patch of skin helped researchers save the life of a young boy battling a deadly disease

 

EB boy

After receiving his new skin, the boy plays on the grounds of the hospital in Bochum, Germany. Credit: RUB

By any standards epidermolysis bullosa (EB) is a nasty disease. It’s a genetic condition that causes the skin to blister, break and tear off. At best, it’s painful and disfiguring. At worst, it can be fatal. Now researchers in Italy have come up with an approach that could offer hope for people battling the condition.

EB is caused by genetic mutations that leave the top layer of skin unable to anchor to inner layers. People born with EB are often called “Butterfly Children” because, as the analogy goes, their skin is as fragile as the wings of a butterfly. There are no cures and the only treatment involves constantly dressing the skin, sometimes several times a day. With each change of dressing, layers of skin can be peeled away, causing pain.

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Hands of a person with EB

Life and death for one boy

For Hassan, a seven-year old boy admitted to the Burn Unit of the Children’s Hospital in Bochum, Germany, the condition was particularly severe. Since birth Hassan had repeatedly developed blisters all over his body, but several weeks before being admitted to the hospital his condition took an even more serious turn. He had lost skin on around 80 percent of his body and he was battling severe infections. His life hung in the balance.

Hassan’s form of EB was caused by a mutation in a single gene, called LAMB3. Fortunately, a team of researchers at the University of Modena and Reggio Emilia in Italy had been doing work in this area and had a potential treatment.

To repair the damage the researchers took a leaf out of the way severe burns are treated, using layers of skin to replace the damaged surface. In this case the team took a tiny piece of skin, about half an inch square, from Hassan and, in the laboratory, used a retrovirus to deliver a corrected version of the defective gene into the skin cells.

 

They then used the stem cells in the skin to grow sizable sheets of new skin, ranging in size from about 20 to 60 square inches, and used that to replace the damaged skin.

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In the study, published in the journal Nature, the researchers say the technique worked quickly:

“Upon removal of the non-adhering gauze (ten days after grafting) epidermal engraftment was evident. One month after grafting, epidermal regeneration was stable and complete. Thus approximately 80% of the patient’s TBSA (total body surface area) was restored by the transgenic epidermis.”

The engrafted skin not only covered all the damaged areas, it also proved remarkably durable. In the two years since the surgery the skin has remained, in the words of the researchers, “stable and robust, and does not blister, itch, or require ointment or medications.”

In an interview in Science, Jakub Tolar, an expert on EB at the University of Minnesota, talked about the significance of this study:

“It is very unusual that we would see a publication with a single case study anymore, but this one is a little different. This is one of these [studies] that can determine where the future of the field is going to go.”

Because the treatment focused on one particular genetic mutation it won’t be a cure for all EB patients, but it could provide vital information to help many people with the disease. The researchers identified a particular category of cells that seemed to play a key role in helping repair the skin. These cells, called holoclones, could be an important target for future research.

The researchers also said that if a child is diagnosed with EB at birth then skin cells can be taken and turned into a ready-made supply of the sheets that can be used to treat skin lesions when they develop. This would enable doctors to treat problems before they become serious, rather than have to try and repair the damage later.

As for Hassan, he is now back in school, leading a normal life and is even able to play soccer.

 

 

Stem cell stories that caught our eye: skin grafts fight diabetes, reprogramming the immune system, and Asterias expands spinal cord injury trial sites

Here are the stem cell stories that caught our eye this week.

Skin grafts fight diabetes and obesity.

An interesting new gene therapy strategy for fighting type 1 diabetes and obesity surfaced this week. Scientists from the University of Chicago made genetically engineered skin grafts that secrete a peptide hormone called glucagon-liked peptide-1 (GLP-1). This peptide is released by cells in the intestine and can lower blood sugar levels by stimulating pancreatic islet cells to secrete insulin (a hormone that promotes the absorption of glucose from the blood).

The study, which was published in the journal Cell Stem Cell, used CRISPR gene editing technology to introduce a mutation to the GLP-1 gene in mouse and human skin stem cells. This mutation stabilized the GLP-1 peptide, allowing it to hang around in the blood for longer. The team matured these stem cells into skin grafts that secreted the GLP-1 into the bloodstream of mice when treated with a drug called doxycycline.

When fed a high-fat diet, mice with a skin graft (left), genetically altered to secrete GLP-1 in response to the antibiotic doxycycline, gained less weight than normal mice (right). (Image source: Wu Laboratory, the University of Chicago)

On a normal diet, mice that received the skin graft saw a rise in their insulin levels and a decrease in their blood glucose levels, proving that the gene therapy was working. On a high fat diet, mice with the skin graft became obese, but when they were treated with doxycycline, GLP-1 secreted from their grafts reduced the amount of weight gain. So not only does their engineered skin graft technology look like a promising new strategy to treat type 1 diabetes patients, it also could be used to control obesity. The beauty of the technology is in its simplicity.

An article in Genetic Engineering and Biotechnology News that covered this research explained that Xiaoyang Wu, the senior author on the study, and his team “worked with skin because it is a large organ and easily accessible. The cells multiply quickly and are easily transplanted. And, transplanted cells can be removed, if needed. “Skin is such a beautiful system,” Wu says, noting that its features make it a perfect medium for testing gene therapies.”

Wu concluded that, “This kind of therapy could be potentially effective for many metabolic disorders.” According to GenBio, Wu’s team “is now testing the gene-therapy technique in combination with other medications.” They also hope that a similar strategy could be used to treat patients that can’t make certain proteins like in the blood clotting disorder hemophilia.

How to reprogram your immune system (Kevin McCormack)

When your immune system goes wrong it can cause all manner of problems, from type 1 diabetes to multiple sclerosis and cancer. That’s because an overactive immune system causes the body to attack its own tissues, while an underactive one leaves the body vulnerable to outside threats such as viruses. That’s why scientists have long sought ways to correct those immune dysfunctions.

Now researchers at the Gladstone Institutes in San Francisco think they have found a way to reprogram specific cells in the immune system and restore a sense of health and balance to the body. Their findings are published in the journal Nature.

The researchers identified a drug that targets effector T cells, which get our immune system to defend us against outside threats, and turns them into regulatory T cells, which control our immune system and stops it from attacking our own body.

Why would turning one kind of T cell into another be helpful? Well, in some autoimmune diseases, the effector T cells become overly active and attack healthy tissues and organs, damaging and even destroying them. By converting them to regulatory T cells you can prevent that happening.

In addition, some cancers can hijack regulatory T cells and suppress the immune system, allowing the disease to spread. By turning those cells into effector T cells, you can boost the immune system and give it the strength to fight back and, hopefully, kill the cancer.

In a news release, Gladstone Senior Investigator Sheng Ding, the lead scientists on the study, said their findings could have several applications:

“Our findings could have a significant impact on the treatment of autoimmune diseases, as well as on stem cell and immuno-oncology therapies.” 

Gladstone scientists Sheng Ding (right) and Tao Xu (left) discovered how to reprogram cells in our immune system. (Gladstone Institutes)

CIRM-funded spinal cord injury trial expands clinical sites

We have another update from CIRM’s clinical trial front. Asterias Biotherapeutics, which is testing a stem cell treatment for complete cervical (neck) spinal cord injury, is expanding its clinical sites for its CIRM-funded SCiStar Phase 1/2a trial. The company is currently treating patients at six sites in the US, and will be expanding to include two additional sites at Thomas Jefferson University Hospital in Philadelphia and the UC San Diego Medical Center, which is part of the UCSD Health CIRM Alpha Stem Cell Clinic.

In a company news release, Ed Wirth, Chief Medical Officer of Asterias said,

Ed Wirth

“We are excited about the clinical site openings at Thomas Jefferson University Hospital and UC San Diego Health. These sites provide additional geographical reach and previous experience with spinal cord injury trials to our SCiStar study. We have recently reported completion of enrollment in four out of five cohorts in our SCiStar study so we hope these institutions will also participate in a future, larger study of AST-OPC1.”

The news release also gave a recap of the trial’s positive (but still preliminary) results this year and their plans for completing trial enrollment.

“In June 2017, Asterias reported 9 month data from the AIS-A 10 million cell cohort that showed improvements in arm, hand and finger function observed at 3-months and 6-months following administration of AST-OPC1 were confirmed and in some patients further increased at 9-months. The company intends to complete enrollment of the entire SCiStar study later this year, with multiple safety and efficacy readouts anticipated during the remainder of 2017 and 2018.”

Scientists fix heart disease mutation in human embryos using CRISPR

Last week the scientific community was buzzing with the news that US scientists had genetically modified human embryos using CRISPR gene editing technology. While the story broke before the research was published, many journalists and news outlets weighed in on the study’s findings and the ethical implications they raise. We covered this initial burst of news in last week’s stem cell stories that caught our eye.

Shoukhrat Mitalipov (Leah Nash, New York Times)

After a week of suspense, the highly-anticipated study was published yesterday in the journal Nature. The work was led by senior author Dr. Shoukhrat Mitalipov from Oregon Health and Sciences University (and a member of CIRM’s Grants Working Group, the panel of experts who review applications to us for funding) in collaboration with scientists from the Salk Institute and Korea’s Institute for Basic Science.

In brief, the study revealed that the teams’ CRISPR technology could correct a genetic mutation that causes a disease called hypertrophic cardiomyopathy (HCM) in 72% of human embryos without causing off-target effects, which are unwanted genome modifications caused by CRISPR. These findings are a big improvement over previous studies by other groups that had issues with off-target effects and mosaicism, where CRISPR only correctly modifies mutations in some but not all cells in an embryo.

Newly fertilized eggs before gene editing, left, and embryos after gene editing and a few rounds of cell division. (Image from Shoukrat Mitalipov in New York Times)

Mitalipov spoke to STATnews about a particularly interesting discovery that he and the other scientists made in the Nature study,

“The main finding is that the CRISPR’d embryos did not accept the “repair DNA” that the scientists expected them to use as a replacement for the mutated gene deleted by CRISPR, which the embryos inherited from their father. Instead, the embryos used the mother’s version of the gene, called the homologue.”

Sharon Begley, the author of the STATnews article, argued that this discovery means that “designer babies” aren’t just around the corner.

“If embryos resist taking up synthetic DNA after CRISPR has deleted an unwanted gene, then “designer babies,” created by inserting a gene for a desirable trait into an embryo, will likely be more difficult than expected.”

Ed Yong from the Atlantic also took a similar stance towards Mitalipov’s study in his article titled “The Designer Baby Era is Not Upon Us”. He wrote,

“The bigger worry is that gene-editing could be used to make people stronger, smarter, or taller, paving the way for a new eugenics, and widening the already substantial gaps between the wealthy and poor. But many geneticists believe that such a future is fundamentally unlikely because complex traits like height and intelligence are the work of hundreds or thousands of genes, each of which have a tiny effect. The prospect of editing them all is implausible. And since genes are so thoroughly interconnected, it may be impossible to edit one particular trait without also affecting many others.”

Dr. Juan Carlos Izpisua Belmonte, who’s a corresponding author on the paper and a former CIRM grantee from the Salk Institute, commented on the impact that this research could have on human health in a Salk news release.

Co-authors Juan Carlos Izpisua Belmonte and Jun Wu. (Salk Institute)

“Thanks to advances in stem cell technologies and gene editing, we are finally starting to address disease-causing mutations that impact potentially millions of people. Gene editing is still in its infancy so even though this preliminary effort was found to be safe and effective, it is crucial that we continue to proceed with the utmost caution, paying the highest attention to ethical considerations.”

Pam Belluck from The New York Times also suggested that this research could have a significant impact on how we prevent disease in newborns.

“This research marks a major milestone and, while a long way from clinical use, it raises the prospect that gene editing may one day protect babies from a variety of hereditary conditions.”

So when will the dawn of CRISPR babies arrive? Ed Yong took a stab at answering this million dollar question with help from experts in the field.

“Not for a while. The technique would need to be refined, tested on non-human primates, and shown to be safe. “The safety studies would likely take 10 to 15 years before FDA or other regulators would even consider allowing clinical trials,” wrote bioethicist Hank Greely in a piece for Scientific American. “The Mitalipov research could mean that moment is 9 years and 10 months away instead of 10 years, but it is not close.” In the meantime, Mitalipov’s colleague Sanjiv Kaul says, “We’ll get the method to perfection so that when it’s possible to use it in a clinical trial, we can.”

Stem Cell Stories that Caught our Eye: CRISPRing Human Embryos, brain stem cells slow aging & BrainStorm ALS trial joins CIRM Alpha Clinics

Here are the stem cell stories that caught our eye this week. Enjoy!

Scientists claim first CRISPR editing of human embryos in the US.

Here’s the big story this week. Scientists from Portland, Oregon claim they genetically modified human embryos using the CRISPR/Cas9 gene editing technology. While their results have yet to be published in a peer review journal (though the team say they are going to be published in a prominent journal next month), if they prove true, the study will be the first successful attempt to modify human embryos in the US.

A representation of an embryo being fertilized. Scientists can inject CRISPR during fertilization to correct genetic disorders. (Getty Images).

Steve Connor from MIT Technology Review broke the story earlier this week noting that the only reports of human embryo modification were published by Chinese scientists. The China studies revealed troubling findings. CRISPR caused “off-target” effects, a situation where the CRISPR machinery randomly introduces genetic errors in a cell’s DNA, in the embryos. It also caused mosaicism, a condition where the desired DNA sequences aren’t genetically corrected in all the cells of an embryo producing an individual with cells that have different genomes. Putting aside the ethical conundrum of modifying human embryos, these studies suggested that current gene editing technologies weren’t accurate enough to safely modify human embryos.

But a new chapter in human embryo modification is beginning. Shoukhrat Mitalipov (who is a member of CIRM’s Grants Working Group, the panel of scientific experts that reviews our funding applications) and his team from the Oregon Health and Science University said that they have developed a method to successfully modify donated human embryos that avoids the problems experienced by the Chinese scientists. The team found that introducing CRISPR at the same time an embryo was being fertilized led to successful correction of disease-causing mutations while avoiding mosaicism and “off-target” effects. They grew these embryos for a few days to confirm that the genetic modifications had worked before destroying them.

The MIT piece quoted a scientist who knows of Mitalipov’s work,

“It is proof of principle that it can work. They significantly reduced mosaicism. I don’t think it’s the start of clinical trials yet, but it does take it further than anyone has before.”

Does this discovery, if it’s true, open the door further for the creation of designer babies? For discussions about the future scientific and ethical implications of this research, I recommend reading Paul Knoepfler’s blog, this piece by Megan Molteni in Wired Magazine and Jessica Berg’s article in The Conversation.

Brain stem cells slow aging in mice

The quest for eternal youth might be one step closer thanks to a new study published this week in the journal Nature. Scientists from the Albert Einstein College of Medicine in New York discovered that stem cells found in an area of the brain called the hypothalamus can slow the aging process in mice.

The hypothalamus is located smack in the center of your brain near the brain stem. It’s responsible for essential metabolic functions such as making and secreting hormones, managing body temperature and controlling feelings of hunger and thirst. Because the body’s metabolic functions decline with age, scientists have suspected that the hypothalamus plays a role in aging.

The mouse hypothalamus. (NIH, Wikimedia).

In the current study, the team found that stem cells in the hypothalamus gradually disappear as mice age. They were curious whether the disappearance of these stem cells could jump start the aging process. When they removed these stem cells, the mice showed more advanced mental and physical signs of aging compared to untreated mice.

They also conducted the opposite experiment where they transplanted hypothalamic stem cells taken from baby mice (the idea being that these stem cells would exhibit more “youthful” qualities) into the brains of middle-aged mice and saw improvements in mental and physical functions and a 10% increase in lifespan.

So what is it about these specific stem cells that slows down aging? Do they replenish the aging brain with new healthy cells or do they secrete factors that keep the brain healthy? Interestingly, the scientists found that these stem cells secreted vesicles that contained microRNAs, which are molecules that regulate gene expression by turning genes on or off.

They injected these microRNAs into the brains of middle-aged mice and found that they reversed symptoms of aging including cognitive decline and muscle degeneration. Furthermore, when they removed hypothalamic stem cells from middle-aged mice and treated them with the microRNAs, they saw the same anti-aging effects.

In an interview with Nature News, senior author on the study, Dongsheng Cai, commented that hypothalamic stem cells could have multiple ways of regulating aging and that microRNAs are just one of their tools. For this research to translate into an anti-aging therapy, “Cai suspects that anti-ageing therapies targeting the hypothalamus would need to be administered in middle age, before a person’s muscles and metabolism have degenerated beyond a point that could be reversed.”

This study and its “Fountain of Youth” implications has received ample attention from the media. You can read more coverage from The Scientist, GenBio, and the original Albert Einstein press release.

BrainStorm ALS trial joins the CIRM Alpha Clinics

Last month, the CIRM Board approved $15.9 million in funding for BrainStorm Cell Therapeutic’s Phase 3 trial that’s testing a stem cell therapy to treat patients with a devastating neurodegenerative disease called amyotrophic lateral sclerosis or ALS (also known as Lou Gehrig’s disease).

The stem cell therapy, called NurOwn®, is made of mesenchymal stem cells extracted from a patient’s bone marrow. The stem cells are genetically modified to secrete neurotrophic factors that keep neurons in the brain healthy and prevent their destruction by diseases like ALS.

BrainStorm has tested NurOwn in early stage clinical trials in Israel and in a Phase 2 study in the US. These trials revealed that the treatment was “safe and well tolerated” and that “NurOwn also achieved multiple secondary efficacy endpoints, showing clear evidence of a clinically meaningful benefit.  Notably, response rates were higher for NurOwn-treated subjects compared to placebo at all time points in the study out to 24 weeks.”

This week, BrainStorm announced that it will launch its Phase 3 CIRM-funded trial at the UC Irvine (UCI) CIRM Alpha Stem Cell Clinic. The Alpha Clinics are a network of top medical centers in California that specialize in delivering high quality stem cell clinical trials to patients. UCI is one of four medical centers including UCLA, City of Hope, and UCSD, that make up three Alpha Clinics currently supporting 38 stem cell trials in the state.

Along with UCI, BrainStorm’s Phase 3 trial will also be conducted at two other sites in the US: Mass General Hospital in Boston and California Pacific Medical Center in San Francisco. Chaim Lebovits, President and CEO, commented,

“We are privileged to have UCI and Dr. Namita Goyal join our pivotal Phase 3 study of NurOwn. Adding UCI as an enrolling center with Dr. Goyal as Principal Investigator will make the treatment more accessible to patients in California, and we welcome the opportunity to work with this prestigious institution.”

Before the Phase 3 trial can launch at UCI, it needs to be approved by our federal regulatory agency, the Food and Drug Administration (FDA), and an Institutional Review Board (IRB), which is an independent ethics committee that reviews biomedical research on human subjects. Both these steps are required to ensure that a therapy is safe to test in patients.

With promising data from their Phase 1 and 2 trials, BrainStorm’s Phase 3 trial will likely get the green light to move forward. Dr. Goyal, who will lead the trial at the UCI Alpha Clinic, concluded:

“NurOwn is a very promising treatment with compelling Phase 2 data in patients with ALS; we look forward to further advancing it in clinical development and confirming the therapeutic benefit with Brainstorm.”

Live streaming genes in living cells coming to a computer near you!

Christmas has come early to scientists at the University of Virginia School of Medicine. They’ve developed a technology that allows you to watch how individual genes move and interact in living cells. You can think of it as Facebook’s live streaming meets the adventurous Ms. Frizzle and her Magic School Bus.

Using a gene editing system called CRISPR/Cas9, the team tagged genes of interest with fluorescent proteins that light up under a microscope – allowing them to watch in real time where these genes are in a cell’s nucleus and how they interact with other genes in the genome. This research, which was funded in part by a CIRM Research Leadership award, was published in the journal Nature Communications.

Watching genes in living cells

Traditional methods for observing the locations of genes within cells, such as fluorescent in situ hybridization (FISH), kill the cells – giving scientists only a snapshot of the complex interactions between genes. With this new technology, scientists can track genes in living cells and generate a 3D map of where genes are located within chromatin (the DNA/protein complex that makes up our chromosomes) during the different stages of a cell’s existence. They can also use these maps to understand changes in gene interactions caused by diseases like cancer.

Senior author on the study, Dr. Mazhar Adli, explained in a news release:

Mazhar Adli (Josh Barney, UVA Health System)

“This has been a dream for a long time. We are able to image basically any region in the genome that we want, in real time, in living cells. It works beautifully. With the traditional method, which is the gold standard, basically you will never be able to get this kind of data, because you have to kill the cells to get the imaging. But here we are doing it in live cells and in real time.”

Additionally, this new technique helps scientists conceptualize the position of genes in a 3D rather than in a linear fashion.

“We have two meters of DNA folded into a nucleus that is so tiny that 10,000 of them will fit onto the tip of a needle,” Adli explained. “We know that DNA is not linear but forms these loops, these large, three-dimensional loops. We want to basically image those kind of interactions and get an idea of how the genome is organized in three-dimensional space, because that’s functionally important.”

Not only can this CRISPR technology light up specific genes of interest, but it can also turn their activity on or off, allowing the scientists to observe the effects of one gene’s activity on others. The flexibility of this approach for visualizing genes in live cells is something that the research world currently lacks.

“We were told we would never be able to do this. There are some approaches that let you look at three-dimensional organization. But you do that experiment on hundreds of millions of cells, and you have to kill them to do it. Here, we can look at the single-cell level, and the cell is still alive, and we can take movies of what’s happening inside.”

This is a pretty nifty imaging tool for scientists that allows them to watch where genes are located and how they move as a cell develops and matures. Live-streaming the components of the genetic engine that keeps a cell running could also provide new insights into why certain genetic diseases occur and potentially open doors for developing better treatments.

Scientists tracked specific genomic locations in a living cell over time using their CRISPR/Cas9 technology. (Nature communications)

Stem cell stories that caught our eye: glowing stem cells and new insights into Zika and SCID

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.

Glowing stem cells help scientists understand how cells work. (Karen Ring)
It’s easy to notice when something is going wrong. It’s a lot harder to notice when something is going right. The same thing can be said for biology. Scientists dedicate their careers to studying unhealthy cells, trying to understand why people get certain diseases and what’s going wrong at the cellular level to cause these problems. But there is a lot to be said for doing scientific research on healthy cells so that we can better understand what’s happening when cells start to malfunction.

A group from the Allen Institute for Cell Science is doing just this. They used a popular gene-editing technology called CRISPR/Cas9 to genetically modify human stem cell lines so that certain parts inside the cell will glow different colors when observed under a fluorescent microscope. Specifically, the scientists inserted the genetic code to produce fluorescent proteins in both the nucleus and the mitochondria of the stem cells. The final result is a tool that allows scientists to study how stem cells specialize into mature cells in various tissues and organs.

Glowing human stem cells. The edges of the cells are shown in purple while the DNA in the cell’s nucleus is in blue. (Allen Institute for Cell Science).

Glowing human stem cells. The edges of the cells are shown in purple while the DNA in the cell’s nucleus is in blue. (Allen Institute for Cell Science).

The director of stem cells and gene editing at the Allen Institute, Ruwanthi Gunawardane, explained how their technology improves upon previous methods for getting cells to glow in an interview with Forbes:

 “We’re trying to understand how the cell behaves, how it functions, but flooding it with some external protein can really mess it up. The CRISPR system allows us to go into the DNA—the blueprint—and insert a gene that allows the cell to express the protein in its normal environment. Then, through live imaging, we can watch the cell and understand how it works.”

The team has made five of these glowing stem cell lines available for use by the scientific community through the Coriell Institute for Medical Research (which also works closely with the CIRM iPSC Initiative). Each cell line is unique and has a different cellular structure that glows. You can learn more about these cell lines on the Coriell Allen Institute webpage and by watching this video:

 

Zika can take multiple routes to infect a child’s brain. (Kevin McCormack)
One of the biggest health stories of 2016 has been the rapid, indeed alarming, spread of the Zika virus. It went from an obscure virus to a global epidemic found in more than 70 countries.

The major concern about the virus is its ability to cause brain defects in the developing brain. Now researchers at Harvard have found that it can do this in more ways than previously believed.

Up till now, it was believed that Zika does its damage by grabbing onto a protein called AXL on the surface of brain cells called neural progenitor cells (NPCs). However, the study, published in the journal Cell Stem Cell, showed that even when AXL was blocked, Zika still managed to infiltrate the brain.

Using induced pluripotent stem cell technology, the researchers were able to create NPCs and then modify them so they had no AXL expression. That should, in theory, have been able to block the Zika virus. But when they exposed those cells to the virus they found they were infected just as much as ordinary brain cells exposed to the virus were.

Caption: Zika virus (light blue) spreads through a three-dimensional model of a developing brain. Image by Max Salick and Nathaniel Kirkpatrick/Novartis

Caption: Zika virus (light blue) spreads through a three-dimensional model of a developing brain. Image by Max Salick and Nathaniel Kirkpatrick/Novartis

In a story in the Harvard Gazette, Kevin Eggan, one of the lead researchers, said this shows scientists need to re-think their approach to countering the virus:

“Our finding really recalibrates this field of research because it tells us we still have to go and find out how Zika is getting into these cells.”

 

Treatment for a severe form of bubble baby disease appears on the horizon. (Todd Dubnicoff)
Without treatment, kids born with bubble baby disease typically die before reaching 12 months of age. Formally called severe combined immunodeficiency (SCID), this genetic blood disorder leaves infants without an effective immune system and unable to fight off even minor infections. A bone marrow stem cell transplant from a matched sibling can treat the disease but this is only available in less than 20 percent of cases and other types of donors carry severe risks.

In what is shaping up to be a life-changing medical breakthrough, a UCLA team has developed a stem cell/gene therapy treatment that corrects the SCID mutation. Over 40 patients have participated to date with a 100% survival rate and CIRM has just awarded the team $20 million to continue clinical trials.

There’s a catch though: other forms of SCID exist. The therapy described above treats SCID patients with a mutation in a gene responsible for producing a protein called ADA. But an inherited mutation in another gene called Artemis, leads to a more severe form of SCID. These Artemis-SCID infants have even less success with a standard bone marrow transplant compared to those with ADA-SCID. Artemis plays a role in DNA damage repair something that occurs during the chemo and radiation therapy sessions that are often necessary for blood marrow transplants. So Artemis-SCID patients are hyper-sensitive to the side of effects of standard treatments.

A recent study by UCSF scientists in Human Gene Therapy, funded in part by CIRM, brings a lot of hope to these Artemis-SCID patient. Using a similar stem cell/gene therapy method, this team collected blood stem cells from the bone marrow of mice with a form of Artemis-SCID. Then they added a good copy of the human Artemis gene to these cells. Transplanting the blood stem cells back to mice, restored their immune systems which paves the way for delivering this approach to clinic to also help the Artemis-SCID patients in desperate need of a treatment.

Advancements in gene editing make blind rats see light

Gene editing is a rapidly advancing technology that scientists are using to manipulate the genomes of cells with precision and accuracy. Many of these experiments are being conducted on stem cells to genetic mutations in an attempt to find cures for various diseases like cancer, HIV and blindness.

Speaking of blindness, researchers from the Salk Institute reported today that they’ve improved upon the current CRISPR/Cas9 gene editing technology and found a more efficient way to edit the genomes of cells in living animals. They used their technology on blind rats that had a genetic disease called retinitis pigmentosa (RP) and found that the rats were able to see light following the treatment.

The really exciting part about their findings is that their CRISPR technology works well on dividing cells like stem cells and progenitor cells, which is typically how scientists use the CRISPR technology, but it also works on adult cells that do not divide – a feat that hasn’t been accomplished before.

Their results, which were published today in the journal Nature, offer a new tool that scientists can use to target cells that no longer divide in tissues and organs like the eye, brain, pancreas and heart.

According to a Salk news release:

“The new Salk technology is ten times more efficient than other methods at incorporating new DNA into cultures of dividing cells, making it a promising tool for both research and medicine. But, more importantly, the Salk technique represents the first time scientists have managed to insert a new gene into a precise DNA location in adult cells that no longer divide, such as those of the eye, brain, pancreas or heart, offering new possibilities for therapeutic applications in these cells.”

CRISPR gene edited neurons, which are non-dividing brain cells, are shown in green while cell nuclei are shown in blue. (Salk)

CRISPR gene edited neurons, which are non-dividing brain cells, are shown in green while cell nuclei are shown in blue. (Salk)

Salk Professor and senior author on the study, Juan Carlos Izpisua Belmonte, explained the big picture of their findings:

“We are very excited by the technology we discovered because it’s something that could not be done before. For the first time, we now have a technology that allows us to modify the DNA of non-dividing cells, to fix broken genes in the brain, heart and liver. It allows us for the first time to be able to dream of curing diseases that we couldn’t before, which is exciting.”

If you want to learn more about the science behind their new CRISPR gene editing technology, check out the Salk news release and coverage in Genetic Engineering & Biotechnology News. You can also watch this short three minute video about the study made by the Salk Institute.