Michael Lorenz, Ph.D.
Published: January 11, 2009 by
assistant professor of microbiology and molecular genetics,
Study of the body’s own fungi could lead to better drugs to fight infection
Viruses, bacteria and fungi live everywhere. They inhabit the air we breathe, the food we eat and the water we drink. So naturally, countless microbes live outside and within our bodies. The immune system works tirelessly to protect us against harmful microbes, all the while creating a harmonious balance between beneficial microbes and those that are harmful.
Most humans have Candida Albicans, a fungus that lives on the skin, mouth, intestinal tract and vagina. However, when our immune systems are weakened by illness, Candida becomes harmful. It can cause a variety of common fungal infections in humans, including oral thrush and vaginal yeast infections.
More importantly, Candida can cause serious bloodstream infections. “Bloodstream infections affect mostly debilitated patients, such as those with cancer, who are undergoing chemotherapy, have recently had an organ transplant, or who have implanted medical devices, such as artificial heart valves or even simply have an intravenous catheter,” said Michael Lorenz, Ph.D.
Lorenz studies the relationship between Candida and the immune system with the goal of identifying better ways to treat patients who are at risk of acquiring an infectious disease.
“Our interest is in how the fungi evade our immune systems to cause disease in people, and we do this using a combination of molecular genetics, genomics, tissue culture and animal studies,” he explained.
It is estimated that 10 percent of bloodstream infections that patients acquire in a hospital are from Candida. Lorenz said that, unfortunately, there are few good drugs on the market to treat fungal infections.
“We do a very poor job of treating these infections, and about four in 10 patients who get invasive candidiasis will die from it,” he said. “With most infectious microbes, we can work to prevent the spread of the disease through hygiene and other measures to limit transmission from person-to-person. We can’t do that with Candida because patients get the disease from themselves.”
Mixing immune cells and Candida cells together in the laboratory and then monitoring how both cells interact has led Lorenz to important findings.
“We have identified that a primary response of Candida on contact with the immune system is to reorganize its cellular physiology,” Lorenz said. “We also are showing that Candida can manipulate the immune cell, weakening its function in very specific ways.”
Lorenz’s findings have biological and clinical outcomes. Namely, he sees the potential for improvements in drug therapies for patients.
“Our findings are interesting from a biological perspective because it shows how this fungal pathogen has adapted to living inside of us in very complex and unexpected ways,” Lorenz said. “From a clinical perspective, many of the processes we have identified are fungal-specific; that is, the enzymes and pathways exist in fungi (and other microbes) but not in mammals. Thus, there is great potential here for drug development.”