Effect of tetra-peptide isolated from interleukin 1 (IL-1) on corneal epithelial wound healing in the rabbit.

To develop a new method for wound healing in case of injured corneal epithelium, the effects of the tetrapeptide (Val-Leu-Leu-Lys), showing the consensus sequence between human interleukin (IL)-1alpha and bovine parotid protein (parotin) on epithelial cell proliferation and elongation were analysed in vitro cell culture experiments on epithelial cells obtained from rabbit cornea. The peptide showed dose-dependent stimulatory effects on epithelial cell proliferation and elongation at 10-100 microg ml(-1)compared with the control experiments. Furthermore, the peptide also exhibited a significant wound healing activity for the epithelial cells in an in situ experiment using mechanically injured rabbit cornea, while the higher concentration of the peptide (100 microg ml(-1)) showed greater efficient results than a previously known agent, sodium hyaluronate (0.3%). In addition, no pyrogenic activity of this peptide was detected by the previously established pyrogenicity test using rabbits. These results suggest that the tetrapeptide (Val-Leu-Leu-Lys) is a promising agent for wound healing in the case of injured corneal epithelium.