pancreatic islet cells

Creating a better way to treat type 1 diabetes

/ Kevin McCormack / 3 Comments

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The cell encapsulation device (right) that is being developed by Encellin, a San Francisco–based biotechnology company. Photo courtesy of Encellin

Type 1 diabetes (t1d) affects every aspect of a person’s life, from what they eat and when they eat, to when they exercise and how they feel physically and emotionally. Because the peak age for being diagnosed with t1d is around 13 or 14 years of age it often hits at a time when a child is already trying to cope with big physical and emotional changes. Add in t1d and you have a difficult time made a lot more challenging.

There are ways to control the disease. Regular blood sugar monitoring and insulin injections can help people manage their condition but those come with their own challenges. Now researchers are taking a variety of different approaches to developing new, innovative ways of helping people with t1d.

One of those companies is Encellin. They are developing a pouch-like device that can be loaded with stem cells and then implanted in the body. The pouch acts like a mini factory, releasing therapies when they are needed.

This work began at UC San Francisco in the lab of Dr. Tejal Desai – with help from CIRM funding – that led to the creation of Encellin. We recently sat down – virtually of course – with Dr. Grace Wei, the co-founder of the company to chat about their work, and their hopes for the future.

Dr. Grace Wei

She said the decision to target t1d was an easy one:

“Type 1 diabetes is an area of great need. It’s very difficult to manage at any age but particularly in children. It affects what they can eat, what they can do, it’s a big burden on the family and can become challenging to manage when people get older.

“It’s an autoimmune disease so everyone’s disease progression is a bit different. People think it’s just a matter of you having too much blood sugar and not enough insulin, but the problem with medicines like insulin is that they are not dynamic, they don’t respond to the needs of your body as they occur. That means people can over-regulate and give themselves too much insulin for what their body needs and if it happens at night, it can be deadly.

Dr. Wei says stem cell research opens up the possibility of developing dynamic therapies, living medicines that are delivered to you by cells that respond to your dynamic needs. That’s where their pouch, called a cell encapsulation device (CED) comes in.

The pouch is tiny, only about the size of a quarter, and it can be placed just under the skin. Encellin is filling the pouch with glucose-sensitive, insulin producing islet cells, the kind of cells destroyed by t1d. The idea is that the cells can monitor blood flow and, when blood sugar is low, secrete insulin to restore it to a healthy level. 

Another advantage of the pouch is that it may eliminate the need for the patient to take immunosuppressive medications.

“The pouch is really a means to protect both the patient receiving the cells and the cells themselves. Your body tends to not like foreign objects shoved into it and the pouch in one respect protects the cells you are trying to put into the person. But you also want to be able to protect the person, and that means knowing where the cells are and having a means to remove them if you need to. That’s why it’s good to have a pouch that you can put in the body, take it out if you need, and replace if needed.”

Dr. Wei says it’s a little like making tea with a tea bag. When the need arises the pouch can secrete insulin but it does so in a carefully controlled manner.

“These are living cells and they are responsive, it’s not medicine where you can overdose, these cells are by nature self-regulating.”

They have already tested their approach with a variety of different kinds of islets, in a variety of different kinds of model.

“We’ve tested for insulin production, glucose stimulation and insulin response. We have tested them in a number of animal models and those studies are supporting our submission for a first-in-human safety clinical trial.”

Dr. Wei says if this approach works it could be used for other metabolic conditions such as parathyroid disorders. And she says a lot of this might not be possible without the early funding and support from CIRM.

“CIRM had the foresight to invest in groups that are looking ahead and said it would be great to have renewable cells to transplant into the body  (that function properly. We are grateful that groundwork that has been laid and are looking forward to advancing this work.”

And we are looking forward to working with them to help advance that work too.

The Top CIRM Blogs of 2019

/ Kevin McCormack / 3 Comments

This year the most widely read blog was actually one we wrote back in 2018. It’s the transcript of a Facebook Live: “Ask the Stem Cell Team” event about strokes and stroke recovery. Because stroke is the third leading cause of death and disability in the US it’s probably no surprise this blog has lasting power. So many people are hoping that stem cells will help them recover from a stroke.

But of the blogs that we wrote and posted this year there’s a really interesting mix of topics.

The most read 2019 blog was about a potential breakthrough in the search for a treatment for type 1 diabetes (T1D).  Two researchers at UC San Francisco, Dr. Matthias Hebrok and Dr. Gopika Nair developed a new method of replacing the insulin-producing cells in the pancreas that are destroyed by type 1 diabetes. 

Dr. Matthias Hebrok
Dr. Gopika Nair

Dr. Hebrok described it as a big advance saying: “We can now generate insulin-producing cells that look and act a lot like the pancreatic beta cells you and I have in our bodies. This is a critical step towards our goal of creating cells that could be transplanted into patients with diabetes.”

It’s not too surprising a blog about type 1 diabetes was at the top. This condition affects around 1.25 million Americans, a huge audience for any potential breakthrough. However, the blog that was the second most read is the exact opposite. It is about a rare disease called cystinosis. How rare? Well, there are only around 500 children and young adults in the US, and just 2,000 worldwide diagnosed with this condition.  

It might be rare but its impact is devastating. A genetic mutation means children with this condition lack the ability to clear an amino acid – cysteine – from their body. The buildup of cysteine leads to damage to the kidneys, eyes, liver, muscles, pancreas and brain.

Dr. Stephanie Cherqui

UC San Diego researcher Dr. Stephanie Cherqui and her team are taking the patient’s own blood stem cells and, in the lab, genetically re-engineering them to correct the mutation, then returning the cells to the patient. It’s hoped this will create a new, healthy blood system free of the disease.

Dr. Cherqui says if it works, this could help not just people with cystinosis but a wide array of other disorders: “We were thrilled that the stem cells and gene therapy worked so well to prevent tissue degeneration in the mouse model of cystinosis. This discovery opened new perspectives in regenerative medicine and in the application to other genetic disorders. Our findings may deliver a completely new paradigm for the treatment of a wide assortment of diseases including kidney and other genetic disorders.”

Sickled cells

The third most read blog was about another rare disease, but one that has been getting a lot of media attention this past year. Sickle cell disease affects around 100,000 Americans, mostly African Americans. In November the Food and Drug Administration (FDA) approved Oxbryta, a new therapy that reduces the likelihood of blood cells becoming sickle shaped and clumping together – causing blockages in blood vessels.

But our blog focused on a stem cell approach that aims to cure the disease altogether. In many ways the researchers in this story are using a very similar approach to the one Dr. Cherqui is using for cystinosis. Genetically correcting the mutation that causes the problem, creating a new, healthy blood system free of the sickle shaped blood cells.

Two other blogs deserve honorable mentions here as well. The first is the story of James O’Brien who lost the sight in his right eye when he was 18 years old and now, 25 years later, has had it restored thanks to stem cells.

The fifth most popular blog of the year was another one about type 1 diabetes. This piece focused on the news that the CIRM Board had awarded more than $11 million to Dr. Peter Stock at UC San Francisco for a clinical trial for T1D. His approach is transplanting donor pancreatic islets and parathyroid glands into patients, hoping this will restore the person’s ability to create their own insulin and control the disease.

2019 was certainly a busy year for CIRM. We are hoping that 2020 will prove equally busy and give us many new advances to write about. You will find them all here, on The Stem Cellar.

Stem Cell Agency Board Approves New Clinical Trial for Type 1 Diabetes

/ Yimy Villa / 5 Comments
Dr. Peter Stock at the capitol in Sacramento in May 2016.
Photo courtesy of Steve German.

Today the governing Board of the California Institute for Regenerative Medicine (CIRM) awarded $11.08 Million to Dr. Peter Stock at the University of California San Francisco (UCSF) to conduct a clinical trial for treatment of Type 1 Diabetes (T1D).

The award brings the total number of CIRM funded clinical trials to 54. 

T1D is a chronic autoimmune disease that affects approximately 1.25 million Americans, with 40,000 new diagnoses each year.  T1D occurs as a result of the body’s immune system destroying its own pancreatic beta cells.  These cells are necessary to produce the vital hormone insulin, which regulates blood sugar levels in the body.  As a result of a lack of insulin, there is no blood sugar control in T1D patients, gradually causing disabling and life-threatening complications such as heart disease, nerve damage, and vision problems.

There is no cure for T1D.  Current treatments consist of blood sugar monitoring and multiple daily injections of insulin.  Transplantation of beta cells, contained in donor pancreatic islets, can reverse the symptoms of diabetes.  However, due to a poor islet survival rate, transplants require islets from multiple donors.  Furthermore, since islet cells are transplanted directly into the vessels that enter the liver, it is extremely difficult to monitor and retrieve these cells should the need arise. 

Dr. Stock’s clinical trial at UCSF aims to address these limitations.  The trial will be using parathyroid glands to aid in the success and viability of the transplant procedure.  Co-transplantation of islets and parathyroid glands, from the same donor, substantially increases beta cell survival, potentially enabling adequate long-term insulin production and removing the need for multiple donors.  Additionally, the co-transplantation will occur in the patient’s forearm, which allows for easier monitoring and improves the effectiveness and accessibility of islet transplants for patients.

“This team’s innovative approach to develop a definitive cell-based treatment for Type 1 Diabetes has the potential to address an unmet medical need that exists despite advancements in diabetes therapy.” says Maria T. Millan, M.D., the President and CEO of CIRM.  “The success of this clinical trial could enable the successful application of islet cell transplants but also of future stem-cell based approaches for diabetes.”

CIRM has funded three other clinical trials for T1D.  One of these was conducted by Caladrius Biosciences and two by ViaCyte, Inc.