Question: I was wondering if you can explain your project in layman’s terms. I don’t understand what islets are; I do get that the sheets will hold something to help with blood sugars, but will that be human- or pig-based? What type of freedom will diabetics have? Will they be able to eat whatever they want, or not worry about lows? Will there be side effects? What makes your ideas better than other companies experimenting with islets? How will it work? What about the hormone Amylin: will that be present? Sorry for the stupid questions,
Jackie
This column is for Jackie and everyone with similar questions.
Please write in the comment section additional questions or clarifications. I will post a revised column a week after this post, on July 26th.
The Islet Sheet is an implantable medical device to regulate glucose in diabetics. The active ingredient is islets of Langerhans, which are clusters of cells found in the pancreas of healthy people. These islets make a set of metabolic hormones — most importantly, insulin.
In people with type 1 (juvenile) diabetes the islets are dead, and make no insulin. Diabetics today inject insulin, often several times a day, and check blood sugars often. A diabetic who has received an Islet Sheet implant will not need to ever inject insulin, and will need to check blood sugars only to test whether the sheet is functioning well.
Each Islet Sheet —a disc about the size of a small sand dollar— contains islets of Langerhans from donor humans or from animals such as pigs. A membrane on the surface of the sheets protects the islets inside from the diabetic’s immune system, which would otherwise quickly destroy them.
The sheets will start functioning as soon as they are implanted, but there may be a period of mutual adaptation, perhaps ten days, while the function of the islets recovers.
The islets in the sheet will sense blood sugar, and release insulin when glucose rises. The insulin secreted by the Islet Sheet will lower blood sugar. The islets will stop secreting insulin when glucose drops to the normal level.
This means that the diabetic will no longer experience severe low blood sugar. It means that, after a meal, blood sugar will rise (as it does in everyone, especially as they age) but will return to the normal level. So diabetics will be able to eat normally, but will experience similar blood sugars to non-diabetics.
The islets in the Islet Sheet are complete, so they have all the normal islet cell types that make hormones in addition to insulin. They will produce, as needed, insulin, glucagon, amylin, etc.
Most likely the first implant of an Islet Sheet into a person will be at the UC Irvine Hospital in Orange, California in 2012 or 2013. Patient selection will be within the parameters set by the FDA and the UCI authorities. Typically these are patients are greater risk because of complications. In the case of type 1 diabetes this is most often hypoglycemia unawareness. We are also evaluating trials overseas because regulatory review can be much faster than in the United States.
Sheet is not a cure. It is a highly sophisticated cell – hydrogel polymer device that delivers insulin with exquisite control. It will not function forever, and will need to be replaced periodically. Perhaps weekly the diabetic will measure their blood sugar after a meal. If it is too high, a visit to the doctor will determine if the sheet is performing within specifications. If not, it will be replaced. We do not yet know the life expectancy of the Islet Sheet, but believe it will be months or even years.
When it becomes available I think you will want to seriously consider the Islet Sheet to treat your type 1 diabetes. The Islet Sheet is the only retrievable and replaceable bio-artificial pancreas. It is the best choice for safety considerations alone.
Please write in the comment section additional questions or clarifications. I will post a revised column a week after this post, on July 26th.
Scott- When will human clinical trials begin and where do you go to be considered? I have been a Type 1 diabetic for over 50 years and have kept myself in excellent shape. I would love to be a part of a breakthrough like this and experience again what it is like not having the condition constantly controlling my life.
Bruce Stevenson
Bruce, excellent questions, many people want to know. I’ll add it to the final version.
Most likely the first implant of an Islet Sheet into a person will be at the UC Irvine Hospital in Orange, California in 2012 or 2013. Patient selection will be within the parameters set by the FDA and the UCI authorities. Typically these are patients are greater risk because of complications. In the case of type 1 diabetes this is most often hypoglycemia unawareness.
It may seem unfair that those of us with good control have to wait longer than those who are more sick, but in the bigger picture that is fair.
We are also evaluating trials overseas because regulatory review can be much faster than in the United States.
Scott King
Are you aware of any studies or similar work being done in Canada? I know regulations differ between this in Canada and the FDA. Are Canadians candidates for a clinical trial?
Jamie, I am not aware of any similar encapsulation research in Canada. But I would point out our project is a Canadian-American collaboration; Jon Lakey is on the faculty of the University of California but remains Canadian.
What will the procedure be like to insert the device? If it will be months to years, will this be major surgery? Where will the device be located?
Ashley, we don’t know yet. At a minimum it will be a simple insertion of Islet Sheet(s) under the skin. It is possible (the evidence is not yet complete) that Islet Sheets will function better intrapertoneal, and be inserted through abdominal keyhole surgery. Even that surgery is considered minor. We should know once we have large animal results next year.