Induction of interleukin-8 in human retinal pigment epithelial cells after denuding injury

AIM To determine interleukin 8 (IL-8) and monocyte chemoattractant protein 1 (MCP-1) expression in response to mechanical injury in human retinal pigment epithelial (HRPE) cells. METHODS Enzyme linked immunosorbent assay (ELISA) was performed to determine IL-8 and MCP-1 secretion by HRPE cells after mechanical denudation. IL-8 and MCP-1 mRNA expression by HRPE cells was assessed using semiquantitative RT-PCR. The effects of immunosuppressive drugs, dexamethasone (DEX) and cyclosporin A (CSA), as well as immunosuppressive cytokines, interleukin 4 (IL-4), interleukin 10 (IL-10), and interleukin 13 (IL-13), on chemokine expression in HRPE cells after denuding injury were analysed. RESULTS Mechanical injury induced HRPE IL-8 mRNA and IL-8 secretion. Although MCP-1 mRNA was enhanced slightly after denuding injury, MCP-1 secretion was not increased. DEX and CSA inhibited HRPE chemokine expression after injury. IL-4 and IL-13 enhanced IL-8 and MCP-1 production by HRPE cells after injury while IL-10 had no effect. CONCLUSIONS These results suggest that IL-8 may be involved in retinal inflammatory responses to injury and that DEX and/or CSA treatment may help control the inflammatory components of retinal diseases such as proliferative vitreoretinopathy.