NEUTROPHIL CHEMOTAXIS INDUCED BY CORNEAL EPITHELIAL-CELLS AFTER HERPES-SIMPLEX VIRUS TYPE-1 INFECTION

Purpose. Neutrophil invasion is a primary event in the development of herpetic keratitis. It has been reported that HSV-1 infection of kerat ocytes induces the synthesis of IL-8, a potent neutrophil chemoattract ant, while corneal epithelium does not. Nevertheless, little is known about the cell-elation between neutrophil migration and the production of chemotactic factors by HSV-l-infected corneal cells, especially in epithelial cells which form an initial barrier of the ocular surface. We examined whether human corneal epithelial cells as well as keratoc ytes could induce neutrophil chemotaxis in response to HSV-1 infection . Methods. Human corneal epithelial cells immortalized with SV40 (HCE) and human keratocytes were infected with HSV-1. The culture fluids co llected at 4, 12, 24 h after infection were assayed for human neutroph il chemotaxis using a modified Boyden chamber method. IL-8 levels in t hese supernatants were measured using enzyme-linked immunosorbent assa y (ELISA). Results. The chemotactic activity induced by HCE and kerato cytes after MP strain of HSV-1 infection peaked as early as 4 h postin fection, then declined. Chemotactic activity induced by HSV-l-infected HCE and IL-8 levels on these supernatants paralleled with the infecti ous virus titer. It was inhibited by monoclonal anti-IL-8 antibody. UV -inactivation of MP strain abrogated neither the induction of chemotac tic activity nor IL-8 secretion of infected HCE. Conclusions. At the e arly phase of HSV-1 infection, corneal epithelial cells play an import ant role in inducing neutrophil chemotaxis, which was mediated by IL-8 .