Appearance of fibronectin in rabbit cornea after thermal burn.

The sequence of the appearance of fibronectin in the rabbit cornea after thermal burn was investigated by indirect immunofluorescent microscopy. One day after thermal burn, the keratocytes disappeared completely from the burned area, and faint fibronectin-specific fluorescence was detected beneath the epithelium and on the stromal side of the Descemet's membrane. On day 3, activated keratocytes began to migrate to the burned lesion. Fibronectin was detected in the burned area as well as in the surrounding uninjured area, and on both sides of the Descemet's membrane. One week after the burn, the keratocytes had increased in the lesion and, concomitantly, fibronectin-specific fluorescence could be observed at the locations corresponding to the keratocytes. Fibronectin in the surrounding area gradually diminished. After 4 weeks, activated keratocytes had accumulated in the lesion, and fibronectin was detected only in the central lesion and at the level of the Descemet's membrane. Thus the appearance of fibronectin was concordant with the appearance of the keratocytes, and this suggests that fibronectin may be involved in the wound-healing of thermally burned rabbit corneas.