Quorum Sensing and Other Collective Regenerative Behaviors in Organ Populations

The document discusses how organ renewal, particularly in the context of hair follicles, can occur through various patterns and mechanisms. It highlights that while individual stem cell and microenvironment interactions have been well-studied, the collective regenerative behaviors at the organ population level have not been as thoroughly examined. The study uses hair growth as an example to demonstrate how organs can renew themselves either continuously or in cycles, and how progenitor cells can be organized in different ways. It suggests that having multiple units of progenitor cells allows for more complex regulation, which can vary by body region and physiological needs, leading to adaptability in different environments. The document also introduces the concept of regenerative waves and quorum sensing as mechanisms that help coordinate the collective behavior of these regenerative units.