Embryonic stem (ES) cells have been proposed to be a powerful tool in the study of
pancreatic disease, as well as a potential source for cell replacement
therapy in the treatment of diabetes. However, data demonstrating the feasibility of using pancreatic islet-like cells differentiated from ES cells remain controversial. In this study we characterized ES cell-derived
insulin-expressing cells and assessed their suitability for the treatment of type I diabetes. ES cell-derived
insulin-stained cell clusters expressed
insulin mRNA and
transcription factors associated with pancreatic development. The majority of
insulin-positive cells in the clusters also showed immunoreactivity for
C-peptide.
Insulin was stored in the cytoplasm and released into the culture medium in a
glucose-dependent manner. When the cultured cells were transplanted into diabetic mice, they reversed the hyperglycemic state for approximately 3 weeks, but the rescue failed due to
immature teratoma formation. Our studies demonstrate that reversal of
hyperglycemia by
transplantation of ES cell-derived
insulin-producing cells is possible. However, the risk of
teratoma formation would need to be eliminated before ES cell-based
therapies for the treatment of diabetes are considered.