Researchers have turned human embryonic stem (hES) cells into a cell type found in human embryos that ultimately forms the pancreas, liver, lungs, and other organs. The ability to generate this primitive cell type - definitive endoderm - is a critical step in the effort to transform hES cells into certain mature cell types that scientists hope will serve as 'replacement cells' to treat various diseases, such as type 1 diabetes or liver failure. The study, by Baetge and colleagues, appears in the December 2005 issue of Nature Biotechnology.
HES cells have the potential to become any specialized cell type in the body. This process happens naturally during development, but reproducing it in the lab - for example, deciphering the complex set of signals that tells a hES cell to become an insulin-producing pancreatic beta cell - is an enormous scientific challenge. Definitive endoderm is one of the three principal (germ) layers of cells in an embryo (in addition to ectoderm and mesoderm), which arise at the very early stage of development known as gastrulation. Understanding how to make definitive endoderm should pave the way to complete differentiation of hES cells to mature endodermal cell types, such as pancreatic beta cells or liver cells.
Dr. Emmanuel Baetge (CyThera Inc., San Diego, CA, USA)
Additional contact for comment:
Patrick Tam (University of Sydney, Australia)
Abstract available online.
(C) Nature Biotechnology press release.
Message posted by: Trevor M. D'Souza