Influence of neural retina on lens fibre differentiation in rats

Lens epithelial explants grown in retina-conditioned medium (RCM) undergo structural and molecular changes characteristic of fibre differentiation in the intact lens. We suggest that in vivo neural retina releases a fibre differentiation factor (FDF) that interacts with equatorial lens epithelial cells and stimulates them to undergo fibre cell differentiation. According to this model, interaction with neural retina is essential for normal lens formation in embryos and for normal lens growth throughout life. Preliminary work on purification of the factor indicates that FDF activity is associated with a high molecular weight complex of 500 kd. The active component of this complex appears to be an 80 kd molecule.