Pod people may look a lot like the real thing, but — as the fictional town of Santa Mira finds out in Invasion of the Body Snatchers — they are disastrously different. The same may be true for reprogrammed stem cells.
These cells are designed to mimic embryonic stem cells and are grown in lab dishes by researchers, not pods by aliens. But scientists now worry that reprogrammed cells, like the duplicates that invaded Santa Mira, may not be wholly satisfactory replacements.
New research suggests that important differences may separate the two kinds of cells. Such differences could impair the ability of reprogrammed cells to make other cell types, which doctors hope to use to repair diseased and damaged tissues. Other limitations of the reprogramming process could leave transplanted cells more susceptible to diseases such as cancer, some scientists fear.