Abstract
Purpose :
Therapies for limbal stem cell deficiency (LSCD) include SC grafts that regenerate the damaged ocular surface. However, the fate of transplanted cells is ill-defined. This study addressed this limitation using corneal epithelial cells from K14-Confetti mice.
Methods :
Cultures of primary corneo-limbal epithelia were generated from K14-Confetti (n=6) and wild-type (WT) (n=3) mice. Cell phenotype and function was ascertained by immunofluorescence, flow cytometry, qPCR and colony formation. K14-Confetti cells were nurtured on fibrin and transferred onto WT mice with experimentally-induced LSCD (n=16) to determine the site of implantation, longevity and phenotype.
Results :
Transgenic and WT cells that were propagated from explanted corneal tissue displayed no phenotypic or functional differences. K14-Confetti corneo-limbal epithelia that engrafted in recipient LSCD WT mice formed 107 ± 36 fluorescent clones at 2-weeks post-procedure, which decreased to 70 ± 5.5 by 6-weeks (p=0.15). Furthermore, cells commonly implanted in the periphery (p<0.05) and some formed clones that migrated centripetally. However, a normal corneal epithelial phenotype was not restored. We speculate this is due to insufficient SCs seeded within grafts, and show evidence of cell loss from the implants and trans-differentiation into K8+-conjunctival and K10+-cutaneous epithelia after transplantation.
Conclusions :
This study successfully tracked the fate of transplanted corneo-limbal epithelia in a mouse model of LSCD by intra-vital microscopy. Our data sheds new light into how donor cells behave, the positions they take, how long they survive and potential mechanisms of loss from the ocular surface. This information is important for improving current SC-based therapies for patients with LSCD.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.