A gut feeling.

The article focuses on the significance of embryology in pointing out better ways of generating endodermal cells from embryonic stem (ES) cells. Researchers have made efforts to generate specialized cell types from ES cells wherein recapitulating in vitro the processes that produce definitive endoderm in the embryo would offer the surest route to differentiating human ES cells into insulin-producing hepatic cells. Significantly, the papers presented describe similar approaches to directing the differentiation of ES cells to definitive endoderm, with differences in the details of the methods and in the resulting cell populations.