In the STERN BioRegion, a broad cooperative project is focusing on the development of methods for the treatment of wounds using medical products.
In many areas, textile products are used in areas that go beyond the products’ traditional function in protecting an injured area from environmental influences. Through the integration of therapeutic substances, such textiles are being turned into innovative medical products providing considerably better wound healing options.
Dr. Dirk Höfer at the Hohenstein Institutes in Bönnigheim is developing textile wound dressings with an integrated active substance repository. The delayed release of the drugs into the area of the wound speeds up the healing process or indeed makes it possible, particularly in the case of chronic wounds. The idea behind this ingenious invention is that the active substances do not originate from a pharmacological design centre but from a living system. The researchers in Hohenstein are using the advantages of a therapy involving enzyme-containing maggot secretions without bringing the maggots themselves directly in contact with the wound. This invention removes emotional difficulties as far as the patients are concerned as well as making treatment a lot easier, both for patients and doctors.
Lucilia sericata maggots were used for the first time in wound treatment in the 1930s and, due to increasing resistance to
antibiotics, are currently experiencing a comeback in modern medicine.
Maintaining function, eliminating disgust factor
In future, it will be possible to bind the wound-healing substances of maggots to textile materials and thus eliminate reservations vis-à-vis this therapy.
“We have decoupled the maggot’s active principle at the wound,” said Höfer who, with his team, has just successfully terminated a BMBF research project on this topic. In a follow-up project, the scientists intend to further develop the new wound dressings into a practical product. “With the first project, we were able to achieve three major goals. These were the production of an active maggot
secretion, the embedding of this secretion into
cellulose as textile carrier and finally the degradation of the carrier material by way of the activity exerted by certain cellulose-degrading maggot
enzymes. We have developed a prototype which dissolves gradually and thus represents a control element for the release
kinetics of the active substances added to the carrier.”
Numerous steps are involved in the process, beginning with the cultivation of maggots, collection and characterisation of the maggots’ secretions and moving on to the therapeutically effective combination of these secretions with textile wound dressings. Apart from human biologist and project coordinator Höfer, the project also integrates other Hohenstein groups such as microbiologists, medical doctors, chemists and textile chemists.
By coupling the wound-healing maggot secretion to a textile carrier which gradually dissolves in the wound thereby releasing the ingredients in a controlled manner, the Hohenstein scientists hope that this form of therapy will in future achieve an even higher acceptance.
Medical doctors from the hospital in Ludwigsburg-Bietigheim are contributing their clinical know-how to the project. They have for many years successfully used maggots in wound healing and provide their knowledge on the specific activities of the maggots. The GMBU (Gesellschaft zur Förderung von Medizin-, Bio- und Umwelttechnologien e.V.) in Jena is in charge of the spectroscopic analysis of the wound areas. “The infrared spectrum of the wound area provides us with information on the state of the wound from which we can draw conclusions on the progress of wound healing,” said Höfer explaining the GMBU’s part of the project.
The original research concept involved the freeze-drying of the collected maggot secretions in order to preserve them for later use, a project in which they have been supported by experts from the University of Kiel. In the meantime, another method has proven more effective. “We have found out that freeze-drying is not necessary. We include the secretions in filaments, which are then air-dried and stabilised. This a lot better for maintaining the activity of the secretions,” said Höfer explaining the new method.
Testing efficacy and safety
Specific knowledge is mandatory when testing the practicability of the product. The scientists at Hohenheim are developing and using tests for assessing the biological efficacy and safety of the product for human health. Human biologists and clinicians are cooperating closely with textile engineers and chemists, investigating the cytotoxicity, sensitisation and irritation potential of the textile medical products.
In the meantime, the scientists have developed a broad range of test methods, which are also used for testing other biotherapeutic wound textiles. Apart from Lucilia sericata maggots, the Hohenstein scientists are also using other animals in their research. For example they are developing moist, textile compresses for abrasions, which are coated with a freeze-dried enzyme secretion obtained from the intestinal tract of deep-sea krill. In addition, the scientists also hope to use the anti-inflammatory and anticoagulant saliva substances of leeches without needing to place the actual animal on the affected areas. This will also be done using medical textiles containing the effective substances.
leh - 20th April 2006
© BIOPRO Baden-Württemberg GmbH
For further information, contact:
Hohenstein Institutes
Dr. Dirk Höfer (Head of the Comptence Centre on Medical Textiles)
74357 Bönnigheim
Phone: +49 (0)7143 271-0
Fax: +49 (0)7143 271-51
E-mail: d.hoefer@hohenstein.de