CHICAGO, Feb. 12 (Xinhua) -- A drug-carrying microsphere within a cell-bearing microcapsule could be the key to transplanting insulin-secreting pig pancreas cells into human patients whose cells themselves have been destroyed by type I diabetes.
According to a study published in the journal Drug Delivery and Translational Research, researchers of University of Illinois (UI) found that insulin-secreting cells, also called islets, showed increased viability and function after spending 21 days inside tiny capsules which contain even tinier capsules bearing a drug that makes the cells more resilient to oxygen deprivation.
UI researchers first used techniques of making microcapsules for various engineering applications and realized that the same techniques could be used for biological applications, such as drug delivery and cell transplants.
The method allows them to use materials of high viscosity to precisely control the size and aspect ratio of the capsules and to produce uniformly sized microcapsules with high throughput.
With such control and high production capacity, the researchers were able to make tiny microspheres that are loaded with a drug which improves cell viability and function in hypoxic conditions.
The microspheres were designed to provide an extended release of the drug over 21 days.
Researchers packaged pig islets and the microspheres together within microcapsules, and compared them with encapsulated islets that didn't have the drug-containing microspheres over the next three weeks.
Around 71 percent of the islets packaged with the drug-releasing microspheres remained viable after 21 days, while only about 45 percent of the islets encapsulated on their own survived.
The cells with the microspheres also maintained their ability to produce insulin in response to glucose at a significantly higher level than those without the microspheres.
In the next step, the researchers hope to test their microsphere-within-a-microcapsule technique in small animals before looking toward larger animal or human trials.
