Abstract
Presentation Description :
In this presentation we address whether multipotent or unipotent stem cells exist in the LG and analyze the relative contribution of stem versus progenitor cells to LG morphogenesis, homeostasis and regeneration. To achieve this, we combine lineage tracing using stochastic unicolor and multicolour lineage specific Cre reporter mouse strains (Krt14, Runx1 and SMA) with analysis of infrequently dividing cells in vivo using a histone 2B (H2B)-GFP label retention system expressed under control of Krt5 promoter. We demonstrate in vivo evidence for a complex epithelial hierarchy using a novel three-dimensional imaging strategy (immunofluorescence tomography). We have highlighted the existence of a small population of adult multipotent stem cell as well as long-lived unipotent lineage specific progenitor cells. We determined that LG morphogenesis during embryonic development and early adulthood is driven by long-lived embryonic progenitor cells, while the adult stem cells are set aside sometime in embryonic development to prevent them from lineage specification and premature differentiation. There is also strong evidence that stem and progenitor cells co-exist in the adult LG and that both populations undergo a dramatic but transient expansion to restore injured LG. Our findings offer promising novel perspectives for the development of new stem cell-based therapies to treat dry eye condition for which there are few or no cures.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.