Gluing instead of stitching wounds-this age-old dream of surgeons has now come true thanks to researchers in the southern Polish city of Katowice.

A group of researchers from the Tissue Bank of the Regional Blood Donation and Blood Therapy Center in Katowice have invented a new-generation dressing that won them a gold medal at the 53rd Eureka World Exhibition of Innovation, Research and New Technology in Brussels in 2004.

Tissue adhesives based on fibrinogen-a protein of the plasma responsible for clotting-actually appeared in the 1980s, bringing the dream a little closer to fulfillment. However, these did not work for extensive traumas to fleshy organs, when bleeding occurred from the entire surface of the liver or spleen, for example. In such situations, the glue is flushed out by the blood. ChitoFib (Chitozan + Fibrinogen) is a new surgical dressing that works in precisely such cases.

The researchers combined tissue glue with chitozan-a natural polymer with excellent absorptive properties and high biocompatibility with human tissues.

Worth their weight in gold

This was not the first time the Katowice researchers used chitozan. A few years earlier, they impressed the international scientific community with another dressing in which the same biopolymer was combined with human placenta extract. ChorioChit (Chorion/placenta + Chitozan), a dressing extremely effective in treating hard-healing wounds, also won a gold medal at a 1999 exhibition in Brussels.

Combining chitozan with another component was innovative on a global scale. Researchers at the Tissue Bank in Katowice developed a completely new generation of dressings, based on chitozan but with two components.

"Similar dressings based on horse or pig collagen are already available," says Dr. Henryk Bursig, head of the Tissue Bank and one of the inventors of ChorioChit and ChitoFib. "The chitozan we have used has the advantage of limiting the risk of transferring zoonotic diseases or viruses. The marine crustaceans from which we take chitozan are much further away from humans in their phylogenetic development than mammals are. This makes the compound safe for the human body. Also, collagen quite often causes allergic reactions, while chitozan does not. The Americans were so excited about this polymer that every U.S. soldier today is equipped with a pure chitozan dressing. Combining this substance with another component is our own, Polish invention, however."

The road to ChorioChit, the first of the two medal-winning dressings, began in the late 1990s when today's Blood Donation and Blood Therapy Center was still the Provincial Blood Donation Station. Placentas from all births ended up here as birth waste. That was when the idea was born to put a placenta-full of nutritious substances stimulating cell growth-on hard-healing wounds. The effects were excellent. Nobody today would use a fresh placenta on a patient, but the seed of an idea had been sown.

In 1989, Bursig, who had just started working at the station, decided to search for a way of combining the placenta with chitozan. In 1997-2000, the Tissue Bank, in association with the Institute of Chemical Fibers in Łódź, worked on a target project of the State Committee for Scientific Research (KBN) called "Starting up the Production of Modified Dressings Made of Placenta Tissue." The result was ChorioChit, a dressing combining microcrystalline chitozan with human placenta extract. Studies showed its efficacy in treating hard-healing wounds, especially ulcerations of the shins. The dressing has a biostimulating and bacteriostatic effect, while also absorbing the discharge from the wound. Because the research in this project was carried out on large animals, namely pigs, ChorioChit is close to being launched as a product. Being an outer dressing, it does not need to go through such restrictive procedures as ChitoFib, which is placed inside the body and stays there for good, much like an implant.

"The cost of making ChorioChit is not huge," Bursig says, "but it does need an investor for implementation, because we at the Tissue Bank are not a production business. We would be happy to sell the technology, though, because the product is ready for application. Somebody would have to deal with the registration and then the launch. I don't think it would take more than two or three years."

Wonder glue

Today Bursig is mainly focused on ChitoFib. Tissue glues have interested him ever since he started working at the Tissue Bank. The idea of gluing a wound instead of stitching it has been present in surgery for a long time. It would be ideal for serious traumas of fleshy internal organs, where suturing is impossible anyway because the organ bleeds from its whole surface. The ideal solution would be a dressing to stop the bleeding that would subsequently disintegrate in the body. That is the essence of a tissue glue: it is supposed to glue a wound, hold it together until it heals, and then dissolve.

ChitoFib has been tested on laboratory animals; they survived after trauma to the liver. It still has to undergo laboratory and clinical tests. Even today, though, its inventors are convinced it meets all the standards needed to receive the European CE mark; it has also been submitted to the Polish Patent Office.

Implementing this dressing in clinical practice will be a watershed in dressing extensive traumas to the fleshy organs that are accompanied by massive bleeding. Today, when faced with traumas to organs such as the liver, spleen or lungs, surgeons have little more at their disposal than a surgical towel to try and stem the blood flow. Such traumas pose a great risk to the patient, so the speed of the doctor's actions and an effective dressing are of paramount importance.

ChitoFib is the perfect solution: it comes in the form of a sterile sponge, ready for use upon unpacking. It fits a wound tightly, absorbs blood very well and has biostimulating properties that help the damaged tissue regenerate.

"Our research was conducted primarily with dressings for the liver in mind, but ChitoFib is also good for stemming bleeding from the spleen, lungs, kidneys and even large blood vessels," Bursig says. The production technology is ready. Tests on large animals and clinical tests are still needed before it can be launched. However, surgeons could apply it even today if their hospital were to apply to the Bioethical Commission for permission to use it in some life-threatening situation.

The holders of the patent for the ChorioChit dressing are Bursig, Stanisław Dyląg, Magdalena Kucharska, Paweł Lampe, Antoni Niekraszewicz, Henryk Struszczyk, Henryk Świerczyński and Alojzy Urbanowski. The ChitoFib dressing has been developed by a team comprising Bursig, Dyląg, Struszczyk, Świerczyński and Jerzy Arendt.

The Regional Blood Donation and Blood Treatment Center in Katowice holds an ISO certificate covering all its operations and containing 19 processes and almost 400 procedures and instructions. Apart from its core activity, the center produces several dozen diagnostic reagents used in blood type serology and in immunohematological tests. The center also carries out scientific research, with many award-winning projects to its credit. Apart from ChorioChit and ChitoFib, three other projects have won the center gold medals at Eureka in Brussels: a blood donation ambulance (2000); Liss-Vera-type standardized model blood cells (2001); and model blood cells, coated, standardized with anti-D serum (2002). The Liss-Vera-type model blood cells also received a special mention at the Concours-Lepine International Invention Show in Paris in 2002 and a bronze medal at a 2002 invention show in Geneva.

Ewa Dereń