Vacillating stem cells
Bone marrow stem cells waver before committing to develop into specialized blood cells
If two roads diverged in a yellow wood, random fluctuations would influence which road stem cells traveled.
A new understanding of how stem cells choose among their possible fates could aid development of stem cell therapies for diseases, scientists say. A type of adult stem cell in bone marrow can develop along one of two paths: either the red or white blood cell lineages. Scientists have wondered why some bone marrow cells follow one path while other, seemingly identical cells go down the other.
New research shows that these bone marrow stem cells are not in fact a single, sharply defined type of cell, but rather have a blurry range of traits. Gene activity determines a cell’s biochemical traits, and for these stem cells, this genetic activity varies over a period of days. Each stem cell slowly “wanders” within the range, sometimes producing proteins that prime the cell for the red blood cell pathway, other times prepping the cell for the white blood cell option.
So a large group of stem cells will always contain a variety of cells covering this complete range of traits, distributed in a familiar bell curve.