Self-renewing stem cells could be 'infinite source' of liver and pancreas cells

Large-scale production of liver and pancreas cells is one step closer, as scientists have developed a cell culture method allowing the relevant stem cells to grow in the laboratory.

The technique could be used in regenerative medicine and the treatment of conditions such as type I diabetes and metabolic liver disease.

Researchers at the Cambridge Stem Cell Institute developed the method, where human foregut stem cells (hFSCs) are produced from human pluripotent stem cells (hPSCs). The hFSCs produced can self-renew and differentiate to become any part of the human foregut, the upper section of the human digestive system.

'These cells have huge implications for regenerative medicine, because they are the precursors to the thyroid upper airways, lungs, liver, pancreas, stomach and biliary systems. We now have a system where we may be able to create all these cell types from the same starting population', said Dr Nicholas Hannan, who led the study.

Human pluripotent stem cells have the ability to grow or mature into all adult cell types. This has previously caused difficulties for scientists trying to grow groups of 'pure' cells, as a mixture of cell types was produced. In this study, the researchers found that switching on certain genes in the hPSCs was able to restrict the number of cell types produced, so that a much purer population of hFSCs was formed.

These purer, self-renewing cells could provide a safer basis for future regenerative therapies, as they 'could strongly reduce the risk of teratomas associated with pluripotent stem cells', the paper states. However, the scientists warn more research is needed, as the liver and pancreas cells generated from hFSCs 'still display a combination of adult and fetal characteristics and are not fully functional'.

Dr Ludovic Vallier, senior author of the study, said: 'What we have now is a better starting point - a sustainable platform for producing liver and pancreatic cells. It will allow us to produce the large number of uncontaminated cells we need for the clinical application of stem cell therapy'.