Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A gentle approach treating microbial keratitis

01.03.2018

Microbial infections of the cornea can have serious consequences, including blindness in the worst case. The treatment of keratitis, a condition caused by certain pathogens, always presents major challenges to ophthalmologists. These corneal infections frequently cannot be successfully treated with the therapies currently available. Fraunhofer researchers are pursuing a new approach: contact lenses with germicidal properties could offer an alternative to conventional therapies. Initial tests in the laboratory and on donor corneas were successful.

Infections of the cornea are a major cause of loss of vision worldwide. The WHO estimates that one in every four losses of eyesight can be attributed to corneal opacity. Usually, the cause of this opacity is microbial keratitis – an inflammation of the cornea caused by germs such as bacteria, fungi, yeasts, viruses or Acanthamoeba.


Germicidal contact lenses show potential for use in treating Acanthamoeba infections.

Fraunhofer IAP

Ophthalmologists fear the type of keratitis caused by Acanthamoeba most of all because it responds poorly to the available drugs. Current therapies combining disinfectants with antibiotics have pronounced side effects and damage the cornea.

In the early stages, the symptoms of Acanthamoeba keratitis are unspecific: the eye turns red, waters and sufferers complain of blurred vision. After five weeks, these symptoms are followed by severe pain – a sign that nerve cells have already been damaged. The disease usually occurs in just one eye. Early diagnosis and treatment are hugely important, because in its latter stages the infection can lead to permanent loss of vision.

Soft contact lenses as cause of Acanthamoeba keratitis

Soft contact lenses are the principal means by which the pathogens are transmitted, accounting for 88 percent of cases. In surveys, patients reported that they had left their contact lenses in for several days or neglected to disinfect them with the proper cleaning solutions, rinsing them under running tap water instead. “Acanthamoeba are essentially everywhere. And contact lenses that are not completely clean are an excellent breeding ground for these parasites.

The amoebae literally eat into the cornea,” explains Dr. Joachim Storsberg, scientist at the Fraunhofer Institute for Applied Polymer Research IAP. As current treatments can take up to a year and are often ineffective, the biomaterials expert and his team – which includes Christopher Plog from the Beuth University of Applied Sciences Berlin, who wrote his thesis on this subject – are carrying out research into innovative, gentle therapies that do not require the use of antibiotics. Contact lenses treated with plasma could turn out to be a promising alternative.

“Plasma is known as a germicide. It has already been successfully used for several years in the treatment of skin diseases. So it made sense to develop contact lenses with germicidal properties and see whether they attack the amoebae and prevent them from multiplying. Together with Prof. Saadettin Sel, an ophthalmologist at Heidelberg University, we came up with the idea of using plasma medicine for this purpose,” says Storsberg. The result is plasma-treated hydrogel lenses, which will be inserted into the eye of infected patients.

Therapeutic contact lenses

To achieve the desired germicidal effect, the researchers chose plasma-activated water (PAW). The atmospheric-pressure plasma was generated by means of dielectric barrier discharge, with the discharge occurring between the electrode and the medium.

The researchers also manufactured the contact lenses themselves. As material they used silicone hydrogel – a soft plastic that swells in water patented by Fraunhofer IAP. “Silicone hydrogel does not react with the plasma-activated water, but absorbs it very effectively without changing its properties,” says Storsberg, describing the advantages of the polymer material. In addition, PAW is easy to produce and does not develop resistance.

“Because of its oxidizing effect, it is able to irreversibly destroy the cell membranes of the amoebae,” says Storsberg. The antibacterial potential of the plasma-treated lenses has been confirmed in all in-vitro experiments, where the PAW hydrogels showed pronounced antimicrobial effects. After growing the amoebae in pure culture, the researchers applied the PAW solution directly to the sample.

Just five minutes later, all amoebae had been inactivated. In further experiments, the researchers infected discarded, no longer transplantable donor corneas with a type species of the Acanthamoeba and covered them with a PAW contact lens. In this test, all the pathogens were also killed. Currently the IAP researchers are investigating whether the hydrogel contact lenses are also suitable for treating mycoses.

In the upcoming clinical trials, which could start as early as this summer, Dr. Storsberg’s team will work together with ophthalmologists to determine how long the PAW-treated lenses can be used to achieve full therapeutic success without damaging the cornea. The research results obtained to date have already been published in journals of ophthalmology.

Weitere Informationen:

https://www.fraunhofer.de/en/press/research-news/2018/March/a-gentle-approach-tr...

Sandra Mehlhase | Fraunhofer Forschung Kompakt

Further reports about: Acanthamoeba IAP Polymer amoebae antibiotics hydrogel keratitis lenses

More articles from Health and Medicine:

nachricht Study tracks inner workings of the brain with new biosensor
16.08.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Foods of the future
15.08.2018 | Georg-August-Universität Göttingen

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>