For millions of patients, a simple bottle of antibiotics is all it takes to wipe out a potentially lethal bacterial infection. But what would happen if those antibiotics were powerless to kill the bugs? That's the terrifying reality for patients who suffer from biofilm infections. Defeating those deadly diseases has become a mission for Associate Professor Mark Shirtliff, PhD.
Dr. Shirtliff was recently honored by the Maryland Biotechnology Center with the 2013 BioMaryland LIFE (Leading Innovative Faculty Entrepreneurs) Prize for his research to develop a vaccine for Staphylococcus aureus. The prize, which includes a $50,000 award, recognizes researchers whose biotechnology advances have the greatest potential for commercial applications. "I felt incredibly honored and very thankful to win the award. I owe a lot of this success to the people in my lab, Dean Stohler and Dr. Patrik Bavoil for supporting my work," states Dr. Shirtliff.
For more than a decade, Dr. Shirtliff has studied the deadly infections that are caused by biofilms. A biofilm is basically a group of bacteria that are stuck in slime, explains Dr. Shirtliff. When bacteria are stuck in a slimy biofilm, antibiotics are no longer able to kill them. While slime may not sound too menacing, infections due to biofilms kill more than half a million people in the U.S. every year. In fact, biofilms are much more prevalent than many people realize. The layer of gunk that coats a person's teeth first thing in the morning is an example of a biofilm. As long as there's a toothbrush nearby, that biofilm doesn't pose much of a threat. "A biofilm is easy to get rid of if it's in your mouth. It's more difficult when it's somewhere else in the body where you can't easily brush it away," Dr. Shirtliff explains.
Biofilm infections can be at their worst when the bacteria are stuck to a foreign object inside the body, like a pacemaker or a metal pin in a broken bone. And even if the body's natural disease-fighting cells manage to isolate the infection, bacteria within the biofilm can detach and spread to other parts of the body, just like cancerous tumors. In the vast majority of cases, the only way to treat the infection is to surgically remove it.
Dr. Shirtliff is convinced that developing a vaccine is the best defense against biofilms. He and his lab members began by isolating five different antigens produced by bacteria in Staphylococcus aureus biofilms. Using an animal model, they combined the antigens into a vaccine and tested it against a Staphylococcus bacterial infection. When all five antigens were used in the vaccine, every single test subject overcame the infection. That success has caught the attention of a major pharmaceutical company, which is currently preparing to test the vaccine in its own animal models.
Not one to rest on his laurels, Dr. Shirtliff continues to study other applications of his model, including how it could be used to create vaccines for other bacterial infections. "Biofilm infections kill hundreds of thousands of people. If I can make an impact and try to eliminate some of the suffering that I've seen, I will have succeeded," he concludes.
Source: University of Maryland School of Dentistry
