Zinc-Removal Technology Prevents Biofilm Formation on Wounds, Implants

Author: 
Shana Leonard
A testament to the belief that there’s strength in numbers, biofilms can be 1000 times more resistant to antibiotics than planktonic bacteria. This level of resistance to antibiotics and host immune responses, coupled with the extreme speed at which they develop, has established biofilms as a leading contributor to hospital-acquired infections and a formidable foe. In an effort to keep these dangerous biofilms at bay, startup company 3G BioTech LLC (Boston) has developed a technology that prevents bacterial colonization on wounds, catheters, pacemakers, orthopedic implants, and other medical devices through zinc removal at the cellular level.

Building on research conducted in the lab of Andrew Herr at the University of Cincinnati (www.uc.edu), 3G BioTech’s technology exploits the scientists’ identification of a ‘zinc zipper’ during the biofilm-formation process. Biofilms form when planktonic bacteria such as Staphylococcus aureus or Staphylococcus epidermidis attach to a substrate. Once anchored to the surface of a medical device, for example, the bacteria colonize and produce an extracellular polysaccharide matrix composed of polysaccharide, protein, and other components, which provides protection.

During this study of biofilms, however, Herr’s team found that a zinc-dependent adhesion module acts like a molecular Velcro or glue, promoting intercellular adhesion. Staphylococcal biofilm formation, the researchers deduced, thus requires cell surface proteins that are zinc-dependent.

In light of this revelation, the researchers tested the effects of zinc chelation, or removal, on biofilm formation. To do so, they employed DTPA, a chelating agent that is approved by FDA for treating heavy-metal poisoning. “We show in our studies that when you remove zinc at the cellular level, biofilms will not form,” Gary Young, CEO and founder of 3G BioTech, said during a presentation at the 2011 BIOMEDevice Boston forum. “Bacteria thus do not have the ability to excrete the polysaccharide matrix to protect themselves, so they’re left in the planktonic state.” Conversely, the scientists found that when zinc was added back in, biofilm formation once again occurred.

“Our mission is clear: to be the first in class commercializing a biofilm prevention product for biolfilm-related infections, reducing healthcare costs and decreasing all of the pain and suffering that goes along with these infections caused by biofilm,” Young said. “There is not an FDA-approved product available that prevents biofilm; it’s all about treatment today.”

3G BioTech’s technology can be incorporated onto the implant or product by the medical device OEM prior to market release, or it can be sold directly to end-users for application in the clinical environment. It can be supplied in spray, gel, cream, or coating form. In addition, the chelating technology can be incorporated into a biodegradable polymer to provide sustained release, according to Young.

Entirely self-funded, privately held 3G BioTech is currently seeking strategic partners for commercialization of the technology within select medical segments, including diabetic wound treatments and various medical implants. Young estimates that the zinc-removal product could go to market within 12 to 18 months of such a partnership. “We think we have an effective therapy in preventing these unmanageable infections [that] also reduces [their] economic and emotional burden,” Young stated. “What we have here is a very elegant, very simple solution to a very large problem.”