Possible regulatory mechanisms of the cornea. I. Epithelial-stromal interaction in vitro
D. BenEzra and T. Tanishima
Electron microscopic studies of pure epithelial and stromal cultures and of
combined cultures demonstrated that keratocytes activity was inhibited by
the presence of epithelial cells in culture. The degradation of collagen
and the formation of clear zones around the keratocytes within the explants
of pure stroma is interpreted as an indication for the production of a
collagenolytic substance by the active keratocytes. The collagenolytic
activity of the keratocytes was not observed within the stroma of combined
cultures and was probably inhibited by the activity of epithelial cells in
these cultures. Furthermore, using a microculture method for the assessment
of the metabolic activity of corneal cells in vitro, supernatants of
epithelial cell cultures were shown to have a marked inhibitory effect on
the capacity of keratocytes to synthesize DNA. No effect of stromal cell
supernatant on epithelial cell activity could be detected by the same
methods. It is suggested that this "one way" influence as observed in vitro
might, in certain conditions, play a role as a regulatory mechanism in
vivo.