Effects of the immunomodulator, VGX-1027, in endotoxin-induced uveitis in Lewis rats

Background and purpose: VGX-1027 is a novel, low molecular weight, immunomodulatory compound that has shown efficacy against a variety of immuno-inflammatory disease models in animals including autoimmune diabetes in NOD mice, collagen-induced arthritis and chemically induced inflammatory colitis. Here, we have studied the effects of VGX-1027 on the development of endotoxin-induced uveitis (EIU) in male Lewis rats, as a model of inflammatory ocular diseases in humans. Experimental approach: EIU was induced by a single footpad injection of 200 mu g lipopolysaccharide (LPS). Groups of rats were treated with either VGX-1027 (25 mg kg(-1)) or its vehicle at different time points (30 min, 6 h or 12 h) after the challenge with LPS or, as positive control, with dexamethasone. The rats were killed within 16 h after LPS challenge, and the eyes and aqueous humor were collected to study serological, immunological and histological signs of EIU. Key results: The rats treated with VGX-1027 within 6 h after LPS challenge exhibited milder clinical, histological and laboratory signs of EIU than those treated with vehicle. Conclusion and implications: This study provides the first evidence that systemic treatment with VGX-1027 counteracts the uveitis-inducing effect of LPS in rats and suggests that this drug may have potential in the treatment of immuno-inflammatory conditions of the eye in humans.