In vitro, the iPS cells readily developed into clusters of cells called embryoid bodies from which cells of virtually any type can develop. These differentiated cells expressed genes for all three embryonic germ layers (the tissues from which all other tissue types in the body develop) and also produced myeloid and granulocyte colonies (types of white blood cells).
The group confirmed that the reprogrammed cells had acquired ES cell characteristics by injecting the newly reprogrammed cells into immunodeficient mice. The cells successfully generated well-differentiated teratomas, benign masses containing all three embryonic germ layers, including respiratory, bone, and neural tissue.
"Not only has this work identified a new programmable cell type, but the cells are easy to obtain and analyze in many research laboratories and bone marrow transplantation centers around the world," said Grover C. Bagby, MD, Professor of Medicine and Molecular and Medical Genetics at Oregon Health and Science University, who is not affiliated with the study. "These findings will immediately enhance the pace of laboratory research in this field and will ultimately help to determine whether iPS cells have a therapeutic potential equivalent to that of embryonic stem cells."
|Contact: Patrick C. Irelan|
American Society of Hematology