Cell Dedifferentiation and Epithelial to Mesenchymal Transitions During Intestinal Regeneration in H. Glaberrima.
Author
Valentín-Tirado, Griselle
Flores, Jaime E.
Rosa, Rey J.
Rivera-Cruz, Angélica
San Miguel-Ruiz, José E.
García-Arrarás, José E.
Tossas, Karen
Type
ArticleDate
2011Metadata
Show full item recordAbstract
Background:
Determining the type and source of cells involved in regenerative processes has been one of the
most important goals of researchers in the field of regeneration biology. We have previously used several cellular
markers to characterize the cells involved in the regeneration of the intestine in the sea cucumber
Holothuria glaberrima
. Results:
We have now obtained a monoclonal antibody that labels the mesothelium; the outer layer of the gut
wall composed of peritoneocytes and myocytes. Using this antibody we studied the role of this tissue layer in the
early stages of intestinal regeneration. We have now shown that the mesothelial cells of the mesentery, specifically
the muscle component, undergo dedifferentiation from very early on in the regeneration process. Cell proliferation,
on the other hand, increases much later, and mainly takes place in the mesothelium or coelomic epithelium of the
regenerating intestinal rudiment. Moreover, we have found that the formation of the intestinal rudiment involves a
novel regenerative mechanism where epithelial cells ingress into the connective tissue and acquire mesenchymal
phenotypes. Conclusions:
Our results strongly suggest that the dedifferentiating mesothelium provides the initial source of cells
for the formation of the intestinal rudiment. At later stages, cell proliferation supplies additional cells necessary for
the increase in size of the regenerate. Our data also shows that the mechanism of epithelial to mesenchymal
transition provides many of the connective tissue cells found in the regenerating intestine. These results present
some new and important information as to the cellular basis of organ regeneration and in particular to the process
of regeneration of visceral organs.