Hidenori Yokoi

A Self-Assembling Peptide Gel as a Vitreous Substitute: A Rabbit Study

Purpose To evaluate a self-assembling peptide gel as a potential vitreous substitute. Methods PanaceaGel SPG-178, a self-assembling peptide gel, was diluted with distilled water and a balanced salt solution to achieve a final peptide concentration of 0.1%. The gels refractive index, visible light transmission rate, and rheologic properties were investigated. The gels biocompatibility was evaluated by examining the cellular viability (live and dead staining) and proliferation rate (alamarBlue assay). A 25-G pars plana vitrectomy was performed on the right eye of 21 New Zealand white rabbits. The gel was then injected into the vitreous cavity of 15 eyes. Six eyes were injected with a balanced salt solution (BSS) and served as controls. Toxicity was examined using electroretinography and histologic analysis after the injection of the gel. Results The gels physical properties closely resembled those of human vitreous. The gel showed no apparent toxicity. When the gel was injected into the vitreous cavity, fragmentation was not observed. Additionally, the gel remained transparent in the vitreous cavity and no complications were observed for 3 months after the injection. Electroretinography and histology confirmed the gels biocompatibility. Conclusions This diluted self-assembling peptide gel could be provide a promising vitreous substitute.