Abstract
Purpose:
The purpose of this study is to develop cell sheet manufacturing technology using cryopreserved human corneal epithelial cells. We evaluate the quality of the cell sheets in vitro and confirm the suitability of the cell sheets in vivo in limbal stem cell deficiency rabbit model.
Methods:
Primary corneal epithelial cells were cultured in serum-free medium with supplements. After detaching by enzymatic treatment, cells were collected and frozen. One of the vials was thawed for quality assessment. Once cells were confirmed to meet the criteria for quality, cells were thawed and cultured to produce cell sheets. The cell sheets were transplanted onto denuded rabbit corneas and monitored for 2 weeks. The engrafted cell sheets were recovered and analyzed by immunohistochemistry.
Results:
We found freezing and thawing does not affect the viability and cell growth of corneal epithelial cells expanded in primary culture. By seeding the post-thawed cells on denuded amniotic membrane, we were able to produce cell sheets with stratified structure. The transplanted cell sheets remained transparent, smooth, and without epithelial defects during the observation period of two weeks.
Conclusions:
Based on the results of in vitro quality tests and in vivo study, the cell sheets using post-thawed cells were confirmed to have the same quality as the cell sheets produced by conventional method. By expanding corneal epithelial cells in primary culture, the number of cell sheets manufactured from one cornea dramatically increased. Moreover, by using cryopreserved cells that meet the certain criteria for quality, it is considered to reduce variation in the quality of the cell sheets.The transplantation of cultivated cell sheets produced with cryopreserved cells could be a promising technique for the treatment of limbal failure.