Eyeworld

20 August 2018 EW NEWS & OPINION Research highlight by Liz Hillman EyeWorld Senior Staff Writer Dr. Storsberg said the results of this research have been presented at conferences, and he and his co-re- searchers are currently filing a man- uscript with a detailed description of the technology's current status for peer-reviewed publication. In a previously published study, Dr. Storsberg and co-investigators showed the efficacy of "plasma-in- duced reactive species" on various microbes, including Staphylococcus aureus, Pseudomonas aeruginosa, Acanthamoeba castellanii, and methi- cillin-resistant Staphylococcus aureus. 5 Numerous investigations regard- ing the use of a plasma-activated therapeutic contact lens for Acan- thamoeba keratitis are still necessary, Dr. Storsberg said. "We are currently at the begin- ning stages toward a new therapy. We've seen that the results are prom- ising," he said. Clinical trials with this thera- peutic contact lens could take place as early as this summer to answer questions such as how long the lens- es need to be worn to combat infec- tion without corneal damage. EW References 1. Ibrahim YW, et al. How could contact lens wearers be at risk of Acanthamoeba infection? A review. J Optom. 2009;2:60–66. 2. Cope JR, et al. Contact lens wearer demographics and risk behaviors for contact lens-related eye infections – United States, 2014. Centers for Disease Control and Preven- tion. Morbidity and Mortality Weekly Report. 2015;64:865–870. 3. Lorenzo-Morales J, et al. An update on Acanthamoeba keratitis: diagnosis, pathogen- esis and treatment. Parasite. 2014;22:10. 4. Chen TP, et al. Plasma-activated water: antibacterial activity and artifacts? Environ Sci Pollut Res Int. 2017. Epub ahead of print. 5. Storsberg J, et al. Towards a new ther- apy concept for acute microbial keratides, including Acanthamoebae. Acta Ophthalmol. 2017;95. Editors' note: Dr. Storsberg has no financial interests related to his comments. Contact information Storsberg: joachim.storsberg@iap.fraunhofer.de both cystic and trophozoite forms" of Acanthamoeba. The authors of this update on Acanthamoeba keratitis also noted that topical antimicrobi- als are frequently used, though some have adverse effects and/or a lack of widespread availability. What's more, dosage with such drugs for these infections needs to be frequent (as much as every hour for several days, tapering to once every few hours over several weeks). 3 Surgical interventions, as well as other more novel options, were also listed as possible therapies. Researchers from the Fraun- hofer Institute for Applied Polymer Research in Potsdam, Germany, with a specialty in making ophthal- mologic implants and biomaterials such as contact lenses, thought a contact lens might provide an easy way to make use of plasma-activated water against such infections, while avoiding the adverse effects and dosing schedule associated with top- ical interventions. Plasma-activated water has been previously shown to provide broad antibacterial effects. 4 Joachim Storsberg, PhD, head of the Department of Biomaterials and Healthcare, Fraunhofer Institute for Applied Polymer Research, said plasma-activated water works against Acanthamoeba in various ways, but its major effect is oxidation of the Acanthamoeba cell membrane, which leads to death of the organism. Plasma-activated water is made from a physical plasma, Dr. Storsberg explained, generated by an electric discharge. Gas, air for example, is ionized and split into its atomic components by this electric discharge and these components create other species, which are very reactive, Dr. Storsberg said. This reactive gas diffuses into water and, for the purposes of the therapeu- tic contact lens, is absorbed into and trapped in the lens to be used against the infectious organism. "We activated water or 0.9% sodium chloride solution and loaded the contact lens," which itself was material created in Dr. Storsberg's lab, he said. "The active reactive molecules inside the water, now 'fixed' in the contact lenses, act in multiple ways against the Acan- thamoeba." ducted a survey that found about 99% of U.S. contact lens wearers reported engaging in at least one of what the CDC deemed to be risk factors for eye infection or inflam- mation. 2 While contact lens wear might be the biggest risk factor for Acan- thamoeba infection, a group of Ger- man researchers have developed a type of therapeutic contact lens that can actually be used to fight such an infection. According to Lorenzo-Morales et al., "there are currently no methods or a single drug that can eliminate Research shows promise for using plasma-activated water against Acanthamoeba infection C ontact lens wear is fre- quently implicated in cases of Acanthamoeba keratitis; one study linked contact lens wear to up to 95% of Acanthamoeba keratitis cases. 1 In 2015, the U.S. Centers for Disease Control and Prevention (CDC) con- Novel therapeutic contact lens designed to tackle Acanthamoeba keratitis Germicidal contact lenses have potential for use in treating Acanthamoeba infections. Source: Fraunhofer Institute for Applied Polymer Research Acanthamoeba are tiny parasites that eat into the cornea of the eye.

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