Self-renewal in the intestinal epithelia is fueled by a population of undifferentiated intestinal stem cells (ISCs) that give rise to daughter or progenitor cells, which can subsequently differentiate into the mature cell types required for normal gut function. The cellular signals that regulate self-renewal are poorly understood and the factors that mediate the transition from a stem cell to a progenitor cell in the gut are unknown. Recent studies have suggested that ISCs are located either at the crypt base interspersed between the Paneth cells (eg, Lgr-5+ve cells) or at or near position 4 within the intestinal crypt (eg, DCAMKL-1 or Bmi-1+ve cells). This raises the possibility that distinct stem cell regions exist in the crypts and that ISC’s state of activation will determine how the self-renewal is regulated in the intestinal tract.
KeywordsIntestinal stem cell (ISC) Self-renewal Transit amplifying (TA) cell Enterocytes Paneth cells Enteroendocrine cells Goblet cells Intestinal crypts Inflammation Radiation
This work was partially supported by National Institutes of Health Grant R01 CA131413 (to SU) from the NCI.
No potential conflict of interest relevant to this article was reported.
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