Localization and ultrastructure of corneal epithelial stem cells in human fetuses
- VernacularTitle:14周至足月胎儿角膜上皮干细胞的分布及超微结构观察
- Author:
Li QIN
;
Bei LIU
;
Cheng PEI
- Publication Type:Journal Article
- Keywords:
fetus;
cornea;
epithelial cell;
stem cell
- From:
Journal of Xi'an Jiaotong University(Medical Sciences)
1982;0(04):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the migrating regulation and ultrastructure of the corneal epithelial stem cells in human fetuses. Methods We examined the corneal cryosections of 14-38 weeks of gestation. Hematoxylin-eosin staining showed the stratified corneal epithelium and the corneal epithelial stem cells were localized by mouse monocolonal antibody against human 64-kilodalton keratin (mAE5), and the ultrastructure of the corneal epithelial stem cells was observed. Results At 14 weeks of gestation, the corneal epithelium was composed of a single basal cells layer and 1-2 superficial squamous cells layers. Some superficial squamous cells were mAE5 positive in the limbus as well as the central and peripheral cornea. At 17-29 weeks of gestation, the limbus epithelium developed from 3 to 5 cells layers and the central region from 2 to 3 cells layers. mAE5 positive cells were found in the suprabasal layers of all 3 regions examined but not in the basal layer. At 33-38 weeks of gestation, the corneal epithelium consisting of 4-6 cells layers was morphologically mature. mAE5 immunoreaction showed the negative cells were confined to limbus basal layer. The ultrastructure of basal layer cells showed they had more heterochromatin in the nucleus, less organells in the cytoplasm and less desmosomes among them. Conclusion The migration of corneal epithelial stem cells in the human fetuses was from the whole layers to basal layer and confined to limbus region finally, and their ultrastructure was immature.
