As someone with a family history of type 1 diabetes (T1D) I know how devastating the condition can be. I also know how challenging it can be to keep it under control and the consequences of failing to do that. Not maintaining healthy blood sugar levels can have a serious impact on the heart, kidney, eyes, nerves, and blood vessels. It can even be fatal.
Right now, controlling T1D means being careful about what you eat, when you eat and how much you eat. It also means regularly checking your blood throughout the day to see if the glucose level is too high or too low. If it’s too high you need to inject insulin; if it’s too low you need to take a fast-acting carbohydrate such as fruit juice or glucose to try and restore it to a healthy level.
That’s why two new approaches to T1D that CIRM has supported are so exciting. They both use small devices implanted under the skin that contain stem cells. The cells can both monitor blood sugar and, if it’s too high, secrete insulin to bring it down.
We sat down with two key members of the Encellin and ViaCyte teams, Dr. Crystal Nyitray and Dr. Manasi Jaiman, to talk about their research, how it works, and what it could mean for people with T1D. That’s in the latest episode of our podcast ‘Talking ‘Bout (re)Generation’.
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.
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.
It’s always gratifying to see research you have helped support go from being an intriguing idea to something with promise to a product that is now the focus of a company. It’s all the more gratifying if the product in question might one day help millions of people battling diabetes.
That’s the case with
a small pouch being developed by a company called Encellin. The pouch is the
brainchild of Tejal Desai, Ph.D., a
professor of bioengineering at UCSF and a CIRM grantee.
“It’s a cell encapsulation device, so this material can essentially protect beta cells from the immune system while allowing them to function by secreting insulin. We are placing stem cell-derived beta cells into the pouch which is then implanted under the skin. The cells are then able to respond to changes in sugar or glucose levels in the blood by pumping out insulin. By placing the device in a place that is accessible we can easily remove it if we have to, but also we can recharge it and put in new cells as well.”
While the pouch was developed in Dr. Desai’s lab, the idea
to take it from a promising item and try to turn it into a real-world therapy
came from one of Dr. Desai’s former students, Crystal Nyitray, Ph.D.
After getting her PhD, Nyitray went to work for the pharmaceutical giant Sanofi. In an article in FierceBiotech she says that’s where she realized that the pouch she had been working on at UCSF had real potential.
“During that time, I started to realize
we really had something, that everything that pharma or biotech was looking at
was something we had been developing from the ground up with those specific
questions in mind,”
So Dr. Nyitray went to work for QB3, the institute created
by UC San Francisco to help startups develop their ideas and get funding. The
experience she gained there gave her the confidence to be the co-founder and
CEO of Encellin.
Dr. Desai is a scientific advisor to Encellin. She says
trying to create a device that contains insulin-secreting cells is not new.
Many previous attempts failed because once the device was placed in the body,
the immune system responded by creating fibrosis or scarring around it which
blocked the ability of the cells to get out.
But she thinks their approach has an advantage over previous
“This is not a new idea, the idea has been around for 40 or
more years but getting it to work is hard. We have a convergence of getting the
right cell types and combining that with our knowledge of immunology and then
the material science where we can design materials at this scale to get the kind
of function that we need.
Dr. Nyitray ““If we can reduce fibrosis, it really
helps the cells get nutrients better, survive better and signal more
effectively. It’s really critical to their success.”
Dr. Desai says the device is still in the early stages of
being tested, but already it’s showing promise.
“We have done testing in animals. Where the company is
taking this is now to see if we can take this to larger animals and then
She says without CIRM’s support none of this would have
“CIRM has been really instrumental in helping us refine the
cell technology piece of it, to get really robust cells and also to support the
development to push the materials, to understand the biology, to really
understand what was happening with the cell material interface. We know we have
a lot of challenges ahead, but we are really excited to see if this could
We are excited too. We are looking forward to seeing what
Encellin does in the coming years. It could change the lives of millions of
people around the world.