Fig. 5: The universal stem cell model.
From: The universal stem cell
The square of colored entities represents marrow stem cells transiting cell cycle. At certain points in cell cycle, they will have a propensity to differentiate into different cell types in the presence of specific tissues or issues from these tissues (extracellular vesicles). They then can act as lung, kidney, brain, heart, or marrow stem cells as illustrated in the figure.
