Abstract
Purpose: :
We have previously shown that the expression of tight junctional proteins in corneal epithelial cells is regulated by corneal fibroblasts in a coculture system. We have now examined the effects of corneal epithelial cells on the expression of intercellular junctional proteins_including connexin43, N-cadherin, ZO-1, occludin, and claudin_in corneal fibroblasts.
Methods: :
Human corneal fibroblasts and simian virus 40-transformed human corneal epithelial (HCE) cells were cultured on opposite sides of a collagen vitrigel membrane. Expression of junctional proteins in corneal fibroblasts was examined by reverse transcription-polymerase chain reaction (RT-PCR) and immunoblot analyses.
Results: :
RT-PCR analysis revealed that the abundance of connexin43 and N-cadherin mRNAs in corneal fibroblasts was increased in the presence of HCE cells compared with that apparent in their absence. Immunoblot analysis also showed that the amounts of connexin43 and N-cadherin in corneal fibroblasts were increased by the presence of HCE cells. The increases in the amounts of these mRNAs and proteins were maximal at 12 and 24 hours, respectively, after the onset of coculture. The amounts of ZO-1, occludin, or claudin mRNAs or proteins in corneal fibroblasts were not affected by the presence of HCE cells.
Conclusions: :
These results suggest that corneal epithelial cells may play an important role in intercellular communication between corneal fibroblasts as well as in maintenance of the three-dimensional network structure of these cells.
Keywords: cornea: basic science • cell-cell communication • cell adhesions/cell junctions