[Interaction between corneal invasion of polymorphonuclear leukocytes and corneal epithelium]

The interaction between corneal invasion of polymorphonuclear leukocytes (PMNs) and corneal epithelium was investigated following different types of corneal injury. Histological examination of centrally denuded corneas demonstrated that it took 18-24 hours for PMNs to infiltrate into the center of the denuded stroma, approximately synchronous with the reepithelialization. On the other hand, in the centrally denuded corneas immediately covered by glue to prevent the reepithelialization, the time required for the appearance of PMNs at the central portion of the corneas was more than 96 hours. Chemotactic activities of PMNs in the conditioned media of normal cornea, completely denuded cornea and reepithelializing cornea were examined using a Boyden chamber. The highest chemotactic activity was defected in the conditioned medium of the cornea with reepithelialization. These data suggest the possibility that the corneal epithelium, especially the re-covering epithelium, stimulates infiltration of the stroma by PMNs.