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bioRxiv · 10.1101/2021.09.13.460167

Development of an in-situ printing system with human platelet lysate based bioink to treat corneal perforation

Abstract

PurposeCorneal perforation is a clinical emergency. Tissue glue to seal the perforation, and supplementary topical medication represents existing standard treatment. Previously, our group developed a transparent human platelet lysate (hPL)-based biomaterial that showed good cell compatibility and accelerated corneal epithelial cells healing in-vitro. This study aims to develop a novel treatment method for corneal perforation using this biomaterial. MethodsRheometry was used to measure the hPL-based biomaterial behaviour at room and corneal surface temperatures. Its adhesiveness to porcine skin and burst pressure limit were also measured. Based on rheological behaviour, a hand-held biopen was developed to extrude it onto the cornea. An animal trial (5 New Zealand white rabbits) to compare impact of the biomaterial and cyanoacrylate glue (control group) on a 2mm perforation was conducted to evaluate safety and efficacy. ResultsThe hPL-based biomaterial showed higher adhesiveness compared to commercial fibrin glue and withstood burst pressure approximately 6.4x higher than routine intraocular pressure. Treatment rabbits had lower pain scores and faster recovery, despite generating similar scar-forming structure compared to controls. No secondary corneal ulcer was generated in rabbits treated with the bio-adhesive. ConclusionsThis study reports a novel in-situ printing system capable of delivering a hPL-based, transparent bio-adhesive and successfully treating small corneal perforations. Bio-adhesive-treated rabbits recovered faster and required no additional analgesia. Both groups showed scarred corneal tissue after healing, however no infection and inflammation was observed by 3 weeks. The delivery system was easy to use and may represent an alternative treatment for corneal perforation. HighlightsO_LIThis study presents a novel in situ printing system to treat corneal perforation C_LIO_LIThe system is comprised of a human platelet lysate-based bio-adhesive and a pen-like hand held delivery system C_LIO_LIMechanical tests showed our transparent bio-adhesive has a higher adhesiveness compared to existing treatments and burst pressure threshold approximately 6.4 times higher than normal intraocular pressure. C_LIO_LIIn vivo rabbit trial showed that compared to cyanoacrylate glue, the bio-adhesive was safer, faster healing and led to less pain in rabbits. C_LI

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BibTeXRIS

You, J., Frazer, H., Sayyar, S., Chen, Z., Liu, X., Taylor, A., Filippi, B., Wise, I., Hodge, C., Wallace, G., Sutton, G.. 2021-09-15. Development of an in-situ printing system with human platelet lysate based bioink to treat corneal perforation. https://doi.org/10.1101/2021.09.13.460167

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