Scientists working for a leading US company Novocell have successfully implanted pancreatic cells produced from human embryonic stem cells (hESCs) into mice. The recent work was reported in 'Nature Biotechnology 2008'. It is hoped that these specialised cells will accelerate research aimed at therapies for diabetes. All of Type 1 diabetes, and a number of Type 2 diabetes, are caused by a deficiency of pancreatic beta cells. These instrumental cells produce an essential hormone (insulin) in the body that regulates blood sugar levels. In the pancreas beta cells are found within small clusters of endocrine cells, the islets of Langerhans, where the hormone is produced. The Scientists at Novocell, based in San Diego, under the supervision of Dr. Emmanuel E. Baetge, derived immature precursor pancreatic beta cells from hESCs. The company has banks of hESCs for this purpose, which are frozen using a Planer controlled rate freezer. Once frozen the samples can then be stored for many years in the vapour phase in large cryogenic tanks.
The hESCs were implanted into mice who lacked their own beta cells, due to chemical removal. Within 90 days the researchers had found that the implanted cells had developed into mature beta cells. The cells were able to function just like normal beta cells and even shared the same morphological and functional characteristics. They produce insulin to help regulate the bodies blood sugar levels. A less sophisticated method currently being tested in humans relies on transplanted islet cells to help treat the symptoms of diabetes but this places a high demand on donors, who are in short supply.
This new method is not entirely risk free due to the possibility of transplantating infected or contaminated cells. A Novocell spokesman said, “The new technology could be the answer scientists have been looking for, as it will provide a continuous supply of clean cells for treatment, as and when the patient requires”.