The brain is a complex part of the human body that allows for the formation of thoughts and consciousness. In many ways it is the essence of who we are as individuals. Because of its importance, our bodies have developed various layers of protection around this vital organ, one of which is called the blood-brain barrier (BBB).
The BBB is a thin border of various cell types around the brain that regulate what can enter the brain tissue through the bloodstream. Its primary purpose is to prevent toxins and other unwanted substances from entering the brain and damaging it. Unfortunately this barrier can also prevent helpful medications, designed to fix problems, from reaching the brain.
Several brain disorders, such as Amyotrophic Lateral Sclerosis (ALS – also known as Lou Gehrig’s disease), Parkinson’s Disease (PD), and Huntington’s Disease (HD) have been linked to defective BBBs that keep out critical biomolecules needed for healthy brain activity.
In a CIRM-funded study, a team at Cedars-Sinai Medical Center created a BBB through the use of stem cells and an Organ-Chip made from induced pluripotent stem cells (iPSCs). These are a specific type of stem cells that can turn into any type of cell in the body and can be generated from a person’s own cells. In this study, iPSCs were created from adult blood samples and used to make the neurons and other supporting cells that make up the BBB. These cells were then placed inside an Organ-Chip which recreates the environment that cells normally experience within the human body.
Inside the 3-D Organ-Chip, the cells were able to form a BBB that functions as it does in the body, with the ability to block entry of certain drugs. Most notably, when the BBB was generated from cell samples of patients with HD, the BBB malfunctioned in the same way that it does in patients with the disease.
These findings expand the potential for personalized medicine for various brain disorders linked to problems in the BBB. In a press release, Dr. Clive Svendsen, director of the Cedars-Sinai Board of Governors Regenerative Medicine Institute and senior author of the study, was quoted as saying,
“The study’s findings open a promising pathway for precision medicine. The possibility of using a patient-specific, multicellular model of a blood barrier on a chip represents a new standard for developing predictive, personalized medicine.”
The full results of the study were published in the scientific journal Cell Stem Cell.
Age-related macular degeneration (AMD) is the leading cause of vision loss in people over 60. It affects 10 million Americans. That’s more than cataracts and glaucoma combined. The causes of AMD are not known but are believed to involve a mixture of hereditary and environmental factors. There is no treatment for it.
Now, in a
CIRM-funded study, researchers at UC San Diego (UCSD) have used stem cells to
help identify genetic elements that could provide some clues as to the cause,
and maybe give some ideas on how to treat it.
Before we get into what the researchers did let’s take a look at what AMD does. At a basic level it attacks the retina, the thin layer of tissue that lines the back of the eye. The retina receives light, turns it into electrical signals and sends it to the brain which turns it into a visual image.
The disease destroys the macula, the part of the retina that controls our central vision. At first, sight becomes blurred or fuzzy but over time it progresses to the point where central vision is almost completely destroyed.
To try and
understand why this happens the team at UCSD took skin samples from six people
with AMD and, using the iPSC method, turned those cells into the kinds of cell found in the retina. Because
these cells came from people who had AMD they now displayed the same
characteristics as AMD-affected retinal cells. This allowed the researchers to
create what is called a “disease-in-a-dish” model that allowed them to see, in
real time, what is happening in AMD.
They were able to
identify a genetic variant that reduces production of a protein called VEGFA,
which is known to promote the growth of new blood vessels.
In a news release Kelly Frazer, director of the Institute for Genomic Medicine at UCSD and the lead author of the study, said the results were unexpected.
“We didn’t start with the VEGFA gene when we went looking for genetic causes of AMD. But we
were surprised to find that with samples from just six people, this genetic
variation clearly emerged as a causal factor.”
Frazer says this
discovery, published in the journal Stem
Cell Reports, could
ultimately lead to new approaches to developing new treatments for AMD.
On the surface, actor Michael J. Fox, singer Neil Diamond, civil rights activist Jesse Jackson and Scottish comedian Billy Connolly would appear to have little in common. Except for one thing. They all have Parkinson’s Disease (PD).
Their celebrity status has helped raise public awareness about the condition, but studies show that awareness doesn’t amount to an understanding of PD or the extent to which it impacts someone’s life. In fact a study in the UK found that many people still don’t think PD is a serious condition.
To try and help change that people around the world will be
holding events today, April 11th, World Parkinson’s Day.
The disease was first described by James Parkinson in 1817 in “An Essay on the Shaking Palsy”. In the essay Parkinson described a pattern of trembling in the hands and fingers, slower movement and loss of balance. Our knowledge about the disease has advanced in the last 200 years and now there are treatments that can help slow down the progression of the disease. But those treatments only last for a while, and so there is a real need for new treatments.
That’s what Jun Takahashi’s team at Kyoto University in
Japan hope to provide. In a first-of-its-kind procedure they took skin cells
from a healthy donor and reprogrammed them to become induced pluripotent stem
cells (iPSCs), or stem cells that become any type of cell. These iPSCs were
then turned into the precursors of dopamine-producing neurons, the cells
destroyed by PD, and implanted into 12 brain regions known to be hotspots for
was carried out in October and the patient, a male in his 50s, is still
healthy. If his symptoms continue to improve and he doesn’t experience any bad
side effects, he will receive a second dose of dopamine-producing stem
cells. Six other patients are scheduled to receive this same treatment.
Earlier tests in monkeys showed that the implanted stem cells improved Parkinson’s symptoms without causing any serious side effects.
Scientists at UC San
Francisco are trying a different approach, using gene therapy to tackle one of
the most widely recognized symptoms of PD, muscle movement.
In the study,
published in the journal Annals
of Neurology, the team used
an inactive virus to deliver a gene to boost production of dopamine in the
brain. In a Phase 1 clinical trial 15 patients, whose medication was no longer
able to fully control their movement disorder, were treated with this approach.
Not only were they able to reduce their medication – up to 42 percent in some
cases – the medication they did take lasted longer before causing dyskinesia,
an involuntary muscle movement that is a common side effect of the PD
In a news article Dr. Chad Christine, the first author of the
study, says this approach may also help reduce other symptoms.
“Since many patients were able to substantially
reduce the amount of Parkinson’s medications, this gene therapy treatment may
also help patients by reducing dose-dependent side effects, such as sleepiness
At CIRM we have
a long history of funding research into PD. Over the years we have invested
more than $55 million to try and develop new treatments for the disease.
In June 2018, the CIRM Board awarded $5.8 million to UC San Francisco’s Krystof Bankiewicz and Cedars-Sinai’s Clive Svendsen. They are using neural progenitor cells, which have the ability to multiply and turn into other kinds of brain cells, and engineering them to express the growth factor GDNF which is known to protect the cells damaged in PD. The hope is that when transplanted into the brain of someone with PD, it will help slow down, or even halt the progression of the disease.
The CIRM funding
will hopefully help the team do the pre-clinical research needed to get the
FDA’s go-ahead to test this approach in a clinical trial.
At the time of the award David Higgins, PhD, the CIRM Board Patient Advocate for Parkinson’s Disease, said: “One of the big frustrations for people with Parkinson’s, and their families and loved ones, is that existing therapies only address the symptoms and do little to slow down or even reverse the progress of the disease. That’s why it’s important to support any project that has the potential to address Parkinson’s at a much deeper, longer-lasting level.”
But we don’t just fund the research, we try to bring the scientific community together to help identify obstacles and overcome them. In March of 2013, in collaboration with the Center for Regenerative Medicine (CRM) of the National Institutes of Health (NIH), we held a two-day workshop on cell therapies for Parkinson’s Disease. The experts outlined the steps needed to help bring the most promising research to patients.
Around one million Americans are currently living with Parkinson’s Disease. Worldwide the number is more than ten million. Those numbers are only expected to increase as the population ages. There is clearly a huge need to develop new treatments and, hopefully one day, a cure.
Till then days like April 11th will be an
opportunity to remind ourselves why this work is so important.
For patients battling cancer for the first time, it can be quite a draining and grueling process. Many treatments are successful and patients go into remission. However, there are instances where the cancer returns in a much more aggressive form. Unfortunately, this was the case for Derek Ruff.
After being in remission for ten years, Derek’s cancer returned as Stage IV colon cancer, meaning that the cancer has spread from the colon to distant organs and tissues. According to statistics from Fight Colorectal Cancer, colorectal cancer is the 2nd leading cause of cancer death among men and women combined in the United States. 1 in 20 people will be diagnosed with colorectal cancer in their lifetime and it is estimated that there will be 140,250 new cases in 2019 alone. Fortunately, Derek was able to enroll in a groundbreaking clinical trial to combat his cancer.
In February 2019, as part of a clinical trial at the Moores Cancer Center at UC San Diego Health in collaboration with Fate Therapeutics, Derek became the first patient in the world to be treated for cancer with human-induced pluripotent stem cells (hiPSCs). hiPSCs are human adult cells, such as those found on the skin, that are reprogrammed into stem cells with the ability to turn into virtually any kind of cell. In this trial, hiPSCs were reprogrammed into natural killer (NK) cells, which are specialized immune cells that are very effective at killing cancer cells, and are aimed at treating Derek’s colon cancer.
A video clip from ABC 10 News San Diego features an interview with Derek and the groundbreaking work being done.
In a public release, Dr. Dan Kaufman, one of the lead investigators of this trial at UC San Diego School of Medicine, was quoted as saying,
“This is a landmark accomplishment for the field of stem cell-based medicine and cancer immunotherapy. This clinical trial represents the first use of cells produced from human induced pluripotent stem cells to better treat and fight cancer.”
In the past, CIRM has given Dr. Kaufman funding related to the development of NK cells. One was a $1.9 million grant for developing a different type of NK cell from hiPSCs, which could also potentially treat patients with lethal cancers. The second grant was a $4.7 million grant for developing NK cells from human embryonic stem cells (hESCs) to potentially treat patients with acute myelogenous leukemia (AML).
In the public release, Dr. Kaufman is also quoted as saying,
“This is a culmination of 15 years of work. My lab was the first to produce natural killer cells from human pluripotent stem cells. Together with Fate Therapeutics, we’ve been able to show in preclinical research that this new strategy to produce pluripotent stem cell-derived natural killer cells can effectively kill cancer cells in cell culture and in mouse models.”
There are limitations to studying cells under a microscope. To understand some of the more complex processes, it is critical to see how these cells behave in an environment that is similar to conditions in the body. The production of organoids has revolutionized this approach.
Organoids are three-dimensional structures derived from stem cells that have similar characteristics of an actual organ. There have been several studies recently published that have used this approach to understand a wide scope of different areas.
In one such instance, researchers at The University of Cambridge were able to grow a “mini-brain” from human stem cells. To demonstrate that this organoid had functional capabilities similar to that of an actual brain, the researchers hooked it up to a mouse spinal cord and surrounding muscle. What they found was remarkable– the “mini-brain” sent electrial signals to the spinal cord that made the surrounding muscles twitch. This model could pave the way for studying neurodegenerative diseases such as spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS).
Speaking of SMA, researchers in Singapore have used organoids to come up with some findings that might be able to help people battling the condition.
SMA is a neurodegenerative disease caused by a protein
deficiency that results in nerve degeneration, paralysis and even premature
death. The fact that it mainly affects children makes it even worse. Not much
is known how SMA develops and even less how to treat or prevent it.
That’s where the research from the A*STAR’s Institute of
Molecular and Cell Biology (IMCB) comes in. Using the iPSC method
they turned tissue samples from healthy people and people with SMA into spinal
They then compared the way the cells
developed in the organoids and found that the motor nerve cells from healthy
people were fully formed by day 35. However, the cells from people with SMA
started to degenerate before they got to that point.
They also found that the protein
problem that causes SMA to develop did so by causing the motor nerve cells to
divide, something they don’t normally do. So, by blocking the mechanism that
caused the cells to divide they were able to prevent the cells from dying.
“We are one of the first labs to report the formation of spinal organoids. Our study presents a new method for culturing human spinal-cord-like tissues that could be crucial for future research.”
Just yesterday the CIRM Board awarded almost $4 million to Ankasa Regenerative Therapeutics to try and develop a treatment for another debilitating back problem called degenerative spondylolisthesis.
And finally, organoid modeling was used to better understand and study an infectious disease. Scientists from the Max Planck Institute for Infection Biology in Berlin created fallopian tube organoids from normal human cells. Fallopian tubes are the pair of tubes found inside women along which the eggs travel from the ovaries to the uterus. The scientists observed the effects of chronic infections of Chlamydia, a sexually transmittable infection. It was discovered that chronic infections lead to permanent changes at the DNA level as the cells age. These changes to DNA are permanent even after the infection is cleared, and could be indicative of the increased risk of cervical cancer observed in women with Chlamydia or those that have contracted it in the past.
Can cell therapy beat the most difficult diseases?
the question posed in a headline in National
Geographic. The answer; maybe, but it is going to take time and
article focuses on the use of iPS cells, the man-made equivalent of embryonic
stem cells that can be turned into any kind of cell or tissue in the body. The
reporter interviews Kemal
Malik, the member of the Board of Management for pharmaceutical giant Bayer who
is responsible for innovation. When it comes to iPS cells, it’s clear Malik is
a true believer in their potential.
“Because every cell
in our bodies can be produced from a stem cell, the applicability of cell
therapy is vast. iPSC technology has the potential to tackle some of the most
challenging diseases on the planet.”
he also acknowledges that the field faces some daunting challenges, including:
How to manufacture
the cells on a large scale without sacrificing quality and purity
How do you create
products that have a stable shelf life and can be stored until needed?
How do you handle
immune reactions if you are giving these cells to patients?
Malik remains confident we can overcome those challenges and realize the full
potential of these cells.
“I believe human
beings are on the cusp of the next big wave of pharmaceutical innovation. The
use of living cells to make people better.”
if to prove Malik right there was also news this week that researchers at
Japan’s Keio University have been given permission to start a clinical trial
using iPS cells to treat people with spinal cord injuries. This would be the
first of its kind anywhere in the world.
Japan launches iPSC clinical trial for spinal cord injury
article in Biospace
says that the researchers plan to treat four patients who have suffered varying
degrees of paralysis due to a spinal cord injury. They will take cells from the patients and,
using the iPS method, turn them into the kind of nerve cells found in the
spinal cord, and then transplant two million of them back into the patient. The
hope is that this will create new connections that restore movement and feeling
in the individuals.
trial is expected to start sometime this summer.
has already funded a first-of-its-kind clinical trial for spinal cord injury
Biotherapeutics. That clinical trial used embryonic stem cells
turned into oligodendrocyte progenitor cells – which develop into cells that support
and protect nerve cells in the central nervous system. We blogged about the
encouraging results from that trial here.
High fat diet drives
Finally today, researchers at Salk have uncovered a possible cause to the rise in colorectal cancer deaths among people under the age of 55; eating too much high fat food.
digestive system works hard to break down the foods we eat and one way it does
that is by using bile acids. Those acids don’t just break down the food,
however, they also break down the lining of our intestines. Fortunately, our
gut has a steady supply of stem cells that can repair and replace that lining.
Unfortunately, at least according to the team from Salk, mutations in these
stem cells can lead to colorectal cancer.
study, published in the journal Cell,
shows that bile acids affect a protein called FXR that is responsible for
ensuring that gut stem cells produce a steady supply of new lining for the gut
wall. When someone eats a high fat diet it upsets the balance of bile acids,
starting a cascade of events that help cancer develop and grow.
release Annette Atkins, a co-author of the study, says there is a
strong connection between bile acid and cancer growth:
“We knew that
high-fat diets and bile acids were both risk factors for cancer, but we weren’t
expecting to find they were both affecting FXR in intestinal stem cells.”
next time you are thinking about having that double bacon cheese burger for
lunch, you might go for the salad instead. Your gut will thank you. And it
might just save your life.
Clive Svendsen, PhD, left, director of the Cedars-Sinai Board of Governors Regenerative Medicine Institute, and Samuel Sances, PhD, a postdoctoral fellow at the institute, with the January 2019 special edition of National Geographic. The magazine cover features a striking image of spinal cord tissue that was shot by Sances in his lab. Photo by Cedars-Sinai.
National Geographic is one of those iconic magazines that everyone knows about but few people read. Which is a shame, because it’s been around since 1888 and has helped make generations of readers aware about the world around them. And now, it’s shifting gears and helping people know more about the world inside them. That’s because a special January edition of National Geographic highlights stem cells.
The issue, called ‘The Future of Medicine’, covers a wide range of issues including stem cell research being done at Cedars-Sinai by Clive Svendsen and his team (CIRM is funding Dr. Svendsen’s work in a clinical trial targeting ALS, you can read about that here). The team is using stem cells and so-called Organ-Chips to develop personalized treatments for individual patients.
Here’s how it works. Scientists take blood or skin cells from individual patients, then using the iPSC method, turn those into the kind of cell in the body that is diseased or damaged. Those cells are then placed inside a device the size of an AA battery where they can be tested against lots of different drugs or compounds to see which ones might help treat that particular problem.
This approach is still in the development phase but if it works it would enable doctors to tailor a treatment to a patient’s specific DNA profile, reducing the risk of complications and, hopefully, increasing the risk it will be successful. Dr. Svendsen says it may sound like science fiction, but this is not far away from being science fact.
“I think we’re entering a new era of medicine—precision medicine. In the future, you’ll have your iPSC line made, generate the cell type in your body that is sick and put it on a chip to understand more about how to treat your disease.”
Dr. Svendsen isn’t the only connection CIRM has to the article. The cover photo for the issue was taken by Sam Sances, PhD, who received a CIRM stem cell research scholarship in 2010-2011. Sam says he’s grateful to CIRM for being a longtime supporter of his work. But then why wouldn’t we be. Sam – who is still just 31 years old – is clearly someone to watch. He got his first research job, as an experimental coordinator, with Pacific Ag Research in San Luis Obispo when he was still in high school.
iPSCs are not just pretty, they’re also pretty remarkable
Two Midwest universities are making headlines for their contributions to stem cell research. Both are developing important tools to advance this field of study, but in two unique ways.
Scientists at the University of Michigan (UM), have compiled an impressive repository of disease-specific stem cell lines. Cell lines are crucial tools for scientists to study the mechanics of different diseases and allows them to do so without animal models. While animal models have important benefits, such as the ability to study a disease within the context of a living mammal, insights gained from such models can be difficult to translate to humans and many diseases do not even have good models to use.
The stem cell lines generated at the Reproductive Sciences Program at UM, are thanks to numerous individuals who donated extra embryos they did not use for in vitro fertilization (IVF). Researchers at UM then screened these embryos for abnormalities associated with different types of disease and generated some 36 different stem cell lines. These have been donated to the National Institute of Health’s (NIH) Human Embryonic Stem Cell Registry, and include cell lines for diseases such as cystic fibrosis, Huntington’s Disease and hemophilia.
Using one such cell line, Dr. Peter Todd at UM, found that the genetic abnormality associated with Fragile X Syndrome, a genetic mutation that results in developmental delays and learning disabilities, can be corrected by using a novel biological tool. Because Fragile X Syndrome does not have a good animal model, this stem cell line was critical for improving our understanding of this disease.
In the next state over, at the University of Wisconsin-Madison (UWM), researchers are doing similar work but using induced pluripotent stem cells (iPSCs) for their work.
The Human Stem Cell Gene Editing Service has proved to be an important resource in expediting research projects across campus. They use CRISPR-Cas9 technology (an efficient method to mutate or edit the DNA of any organism), to generate human stem cell lines that contain disease specific mutations. Researchers use these cell lines to determine how the mutation affects cells and/or how to correct the cellular abnormality the mutation causes. Unlike the work at UM, these stem cell lines are derived from iPSCs which can be generated from easy to obtain human samples, such as skin cells.
The gene editing services at UWM have already proved to be so popular in their short existence that they are considering expanding to be able to accommodate off-campus requests. This highlights the extent to which both CRISPR technology and stem cell research are being used to answer important scientific questions to advance our understanding of disease.
The iPSC Repository was created by CIRM to house a collection of stem cells from thousands of individuals, some healthy, but some with diseases such as heart, lung or liver disease, or disorders such as autism. The goal is for scientists to use these cells to better understand diseases and develop and test new therapies to combat them. This provides an unprecedented opportunity to study the cell types from patients that are affected in disease, but for which cells cannot otherwise be easily obtained in large quantities.
One of the biggest obstacles to transplanting organs from one person to another is that the immune system of the person getting the new life-saving organ often tries to reject it. The immune cells see the new material as “foreign” and attacks it, sometimes destroying it.
Right now, the only way to prevent that is by using powerful immunosuppressive drugs to keep the patient’s immune system at bay and protect the new organ. It’s effective, but it also comes with some long-term health consequences.
But now researchers at Tel Aviv University in Israel say they may have found a way around that, using the patient’s own stem cells.
The team says it was able to take fatty tissue from patients and, using the iPSC procedure, turn them into other kinds of cells to help repair different kinds of tissue.
In a story in the “Times of Israel”, Prof Tal Dvir, the lead researcher, said this new approach could theoretically be used to engineer any tissue type in the body.
“We were able to create a personalized hydrogel from the materials of the biopsy, to differentiate fatty tissue cells into different cell types and to engineer cardiac, spinal cord, cortical and other tissue implants to treat different diseases. Since both the cells and the material used derive from the patient, the implant does not provoke an immune response, ensuring proper regeneration of the defected organ.”
Dvir says the research, published in the journal Advanced Materials, has only been tested in animals so far but has shown great promise, helping regenerate damaged tissues in mice and rats. Their next goal is to see if they can replicate this in people.
“Theoretically we can work in every disease or disorder that cells are involved in, where tissue is dying. We can create the tissue to fix that injury by a simple injection of materials and cells at the injury site,”
While this has long been a goal of many stem cell researchers around the world, problems translating what looks good in animals into what works in people has invariably slowed down the progress of even the most promising approach. At least so far.
Neurons derived from stem cells.Credit: Silvia Riccardi/SPL
Currently, more than 10 million people worldwide live with Parkinson’s disease (PD). By 2020, in the US alone, people living with Parkinson’s are expected to outnumber the cases of multiple sclerosis, muscular dystrophy and Lou Gehrig’s disease combined.
There is no cure for Parkinson’s and treatment options consist of medications that patients ultimately develop tolerance to, or surgical therapies that are expensive. Therefore, therapeutic options that offer long-lasting treatment, or even a cure, are essential for treating PD.
To understand their treatment strategy, however, we first have to understand what causes this disease. Parkinson’s results from decreased numbers of neurons that produce dopamine, a molecule that helps control muscle movements. Without proper dopamine production, patients experience a wide range of movement abnormalities, including the classic tremors that are associated with PD.
The current treatment options only target the symptoms, as opposed to the root cause of the disease. Takashi’s group decided to go directly to the source and improve dopamine production in these patients by correcting the dopaminergic neuron shortage.
The scientists harvested skin cells from a healthy donor and reprogrammed them to become induced pluripotent stem cells (iPSCs), or stem cells that become any type of cell. These iPSCs were then turned into the precursors of dopamine-producing neurons and implanted into 12 brain regions known to be hotspots for dopamine production.
The procedure was carried out in October and the patient, a male in his 50s, is still healthy. If his symptoms continue to improve and he doesn’t experience any bad side effects, he will receive a second dose of dopamine-producing stem cells. Six other patients are scheduled to receive this same treatment and Takashi hopes that, if all goes well, this type of treatment can be ready for the general public by 2023.
This treatment was first tested in monkeys, where the researchers saw that not only did the implanted stem cells improve Parkinson’s symptoms and survive in the brain for at least two years, but they also did not cause any negative side effects.