By: Tori Tucker
When we think of type one diabetes (T1D), we often assume the affected person cannot consume any amount of sugar in his or her diet. This is not the case because the food we oftentimes consume contain carbohydrates that are made up of simple or complex sugars. T1D is actually characterized by the destruction of pancreatic insulin producing beta-cells (islets) that have been destroyed by the body’s own immune system. The affected individual’s cells can no longer consume sugar from the blood because insulin is required for sugar consumption. Currently, T1D treatment involves the individual giving him or herself exogenous insulin injections in the form of a syringe or insulin-pump. Dr. Lakey’s lab at the University of California, Irvine (UCI), has researchers working on a revolutionary technology and islet transplant breakthrough in treating T1D without the need for immunosuppressants. If Dr. Lakey is to make long-lasting islet transplantation possible, type one diabetics will no longer need to worry about daily needle injections
Transplantation methods face a huge issue with the requirement for immunosuppression and immediate oxygen supply to islets after transplantation has occurred . Upon the transplantation of islets, recipients risk rejection of newly transplanted islets. As a result, immunosuppressants are used to suppress the immune system of the recipient to avoid rejection. In addition, islets not receiving enough oxygen after transplantation end up dying as a result. In a normal environment, islets depend on blood vessels for the delivery of oxygen. However, at the site of the transplant, blood vessel formation is not spontaneous. As a result, islets do not receive optimal amounts of oxygen.
To combat the issue faced with islets receiving little to no oxygen, Dr. Lakey and his research team have come up with a method involving the encapsulation of oxygen releasing substances. Now, you may be asking yourself, “What is encapsulation?” Simply, researchers use alginate, a material isolated from brown algae, to encapsulate oxygen-releasing substances such as perfluorocarbons (PFC) [1,2]. These capsules are spherical in shape and help to control the release of oxygen to islets when they are exposed to low levels of oxygen. Alginate creates a barrier allowing oxygen to move out of the capsule containing PFC and to the islet. PFC is a substance studied by Dr. Lakey’s lab due to its affinity for oxygen and is comparable to blood in this way. You can think of hemoglobin in the blood which transports and delivers oxygen to our cells, tissue, and organs. However, PFC substances require oxygen charging in order to provide an adequate supply of oxygen to surrounding islets. PFC has the potential to curb islet cell death due to enhancing islet oxygenation upon initial islet transplantation into diabetic patients.
The big picture is not to simply take islets and put them into a patient with these alginate capsules containing PFC. The goal is to create a bioencapsulation device that can house the islets with surrounding PFC capsules . This technology is being greatly studied by Dr. Lakey’s lab and the engineering department at UCI. The goal is to create an environment for islets to receive oxygen, nutrients, and avoid rejection from the immune system.
1. Krishnan, Rahul, David Ko, Tori Tucker, Emmanuel Opara, Clarence E. Foster, III, David Imagawa, Michael Stamos, and Jonathan RT Lakey. 2016. Strategies to Combat Hypoxia in Encapsulated Islet Transplantation. Surgery: Current Research (2016): OMICS International.
2. Joseph C. White, Megan E. Godsey, Surita R. Bhati. 2014. Perfluorocarbons enhance oxygen transport in alginate-based hydrogels, Polymers for Advanced Technologies, 2014, 25, 11.
3. Joseph C. White, Whitney L. Stoppel, Susan C. Roberts, Surita R. Bhatia. 2013. Addition of perfluorocarbons to alginate hydrogels significantly impacts molecular transport and fracture stress, Journal of Biomedical Materials Research Part A, 2013, 101A, 2.