Effectiveness of Antimicrobial Peptide Immobilization for Preventing Perioperative Cornea Implant-Associated Bacterial Infection

Abstract

Titanium (Ti) is a promising candidate biomaterial for an artificial corneal skirt. Antimicrobial peptide (AMP) immobilization may improve the bactericidal effect of the Ti substrate. In this study, we tested the bactericidal efficacy of a functionalized Ti surface in a rabbit keratitis model. A corneal stromal pocket was created by a femtosecond laser. The Ti films were then inserted into the pocket, and Staphylococcus aureus or Pseudomonas aeruginosa was inoculated into the pocket above the implant films. The corneas with Ti-AMP implants were compared with the corneas implanted with unprotected Ti by slit lamp observation and anterior segment optical coherence tomography (AS-OCT). Inflammatory responses were evaluated by bacterium counting, hematoxylin-eosin staining, and immunostaining. There was a lower incidence and a lesser extent of infection on rabbit corneas with Ti-AMP implants than on those with unprotected Ti implants. The bactericidal effect of AMP against S. aureus was comparable to that of postoperative prophylactic antibiotic treatment; hence, SESB2V AMP bound to the Ti implant provided functional activity in vivo, but its efficacy was greater against S. aureus than against P. aeruginosa. This work suggests that SESB2V AMP can be successfully functionalized in a rabbit keratitis model to prevent perioperative corneal infection.

Application of Graphene as Candidate Biomaterial for Synthetic Keratoprosthesis Skirt

“…The use of Ti as a backplate has been shown to be a double-edged sword, the better adhesion of cells providing improved integration balanced with the increased colonization by biofilm coating organism, noted from explanted KPros. 19,[42][43][44] The potential advantage of using graphene is not only its cellular attachment properties similar to those of Ti but also its reported antibacterial and antifungal activity, which may be advantageous in preventing infection in long-term implanted devices. 45,46 Cell survival and proliferation were higher on G-film than on tissue culture plastic at 7 days of culture.…”

“…They were anesthetized by intramuscular injection of ketamine hydrochloride (35 mg/kg; Parnell Laboratories, Alexandria, NSW, Australia) and xylazine hydrochloride (5 mg/kg; Troy Laboratories, Smithfield, NSW, Australia). The right eyes received corneal stromal pocket creation at midstromal level and implanted with G-film (trephined to 4-mm diameter) as described in our previous work, 19 while the left eyes were the untreated control.…”

“…22 Functionalized Ti substrates have displayed excellent antimicrobial properties that effectively alleviated postsurgery implant-associated infection. 19,20 These studies have expanded the current strategies to improve the biocompatibility and survival rate of implanted synthetic Kpros and demonstrated the excellent biocompatibility of Ti as a biomaterial for synthetic Kpro. However, a solid Ti Kpro may be heavy, and Ti has poor fretting fatigue and tribologic properties (friction, lubrication, and wear), which may be important with continual eye blinking.…”

“…16,17 To further improve the biocompatibility and bactericidal properties of the implants, we functionalized the surface of TiO 2 with antimicrobial peptide coating. 19,20 The nonoxidized, metallic Ti has been used in the Boston KPro, due to its better compatibility compared to PMMA, 21 and the decreased formation of retroprosthetic membranes when Ti was used as a backing plate. 22 Functionalized Ti substrates have displayed excellent antimicrobial properties that effectively alleviated postsurgery implant-associated infection.…”

Optimization of spark plasma sintered titania for potential application as a keratoprosthesis skirt

“…Bioinert materials, such as titanium (Ti) or its alloys, aluminium, and modified compounds may be used as potential KPro skirt materials . Recently, we have shown promising bactericidal properties after functionalization of a Ti surface with antimicrobial peptide coating that could effectively alleviate postsurgery implant‐associated infection . However, Ti and its alloys have poor fretting fatigue and tribological properties (friction, lubrication, and wear), which are important properties with continual eye blinking .…”