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Dedifferentiation as a cell source for organ regeneration
Published in David M. Gardiner, Regenerative Engineering and Developmental Biology, 2017
What follows stem cells’ disappearance is that their immediate progeny, which are cells that are already routed in their differentiation process, backtrack and undergo a partial dedifferentiation, themselves becoming the new stem cells and repopulating the tissue by converting to fully functional stem cells. Eliminating the stem cells from the intestinal luminal epithelium showed the best example of this differentiation reversal. In this tissue, all cell types originate from Lgr5-labeled stem cells within the intestinal crypts (Barker et al. 2008). These cells give rise to transiently dividing cells that migrate toward the tip of the intestinal villi or to the base of the crypt and eventually differentiate into 4–5 cell types. The migration to the tip of the villi is in a linear pathway, as cells remain attached to the epithelium basement membrane. However, if the stem cells are depleted by using genetic methods or toxins, then cells that are advanced in their differentiation path reprogram and become the new stem cells (Li and Clevers 2010, Tian et al. 2011, Roth et al. 2012, Tetteh et al. 2015). In other cases, it has been shown that even fully differentiated cells can dedifferentiate and become stem cells (Desai and Krasnow 2013).
Embryonic arsenic exposure reduces intestinal cell proliferation and alters hepatic IGF mRNA expression in killifish (Fundulus heteroclitus)
Published in Journal of Toxicology and Environmental Health, Part A, 2019
Kaleigh C. Sims, Katey L. Schwendinger, Dana B. Szymkowicz, Jonathan R. Swetenberg, Lisa J. Bain
Intestinal morphogenesis and development are similar in mammals and fish, although most fish lack true crypts and have instead proliferative compartments at the base of the villus (Chin et al. 2017; Ng et al. 2005). Mechanisms driving intestinal cell differentiation appear to be highly conserved in vertebrates and produce the same main cell types: enterocytes, goblet cells, and enteroendocrine cells (Brugman 2016; Olden et al. 2008; Takashima, Gold, and Hartenstein 2013). As in mammals, epithelial cells in zebrafish migrate from the base to the tip of the intestinal fold within 5–7 d (Ng et al. 2005). Cell division in crypts is dependent upon Wnt/β-catenin signaling, in which the Lgr5+ stem cells differentiate into progenitor or transit amplifying cells (Pinto et al. 2003). From the progenitor cells, the Notch ligand Delta turns on transcription factors such as Hes1 to specify enterocyte fate (Merker, Weitz, and Stange 2016; Takashima, Gold, and Hartenstein 2013), while the Ascl and Atoh transcription factors play roles in specification of goblet and enteroendocrine cells (Roach et al. 2013).
Nonwoven membranes for tissue engineering: an overview of cartilage, epithelium, and bone regeneration
Published in Journal of Biomaterials Science, Polymer Edition, 2019
Thalles Canton Trevisol, Rayane Kunert Langbehn, Suellen Battiston, Ana Paula Serafini Immich
In vivo application of nonwoven scaffolds for epithelial tissue regeneration is also reported in further studies [47, 50, 66]. One of them used PGA scaffolds to grow Lgr5-like stem cells in vivo to regenerate the epithelial tissue of the small intestine of a rat. [47] The study was promising and revealed that in the fourth week after the transplantation, the implanted stem cells grew, proliferated and differentiated into four types of epithelial cells.