How would you feel if you were told you are 10 times more bacteria than you are human?
That is not true mass-wise, but according to June Round, the microorganisms living on and in the human body outnumber human cells 10 to one.
Round is an assistant professor in the microbiology and immunology division of the U’s Department of Pathology. She received her Ph.D. at UCLA and then proceeded to postdoctoral research at the California Institute of Technology. Now she is part of a research team at the U.
She believes that with such a high ratio of bacteria to human cells, people might one day begin to redefine themselves according to the microscopic creatures inhabiting their bodies.
“I don’t have any idea what that would look like,” Round said. “It’s just that we’re discovering that the microbes that live on your body can actually impact your behavior. They’re part of who you are.”
Round’s research was the focus of a lecture Thursday evening at the Salt Lake City Library, sponsored by the Natural History Museum of Utah. It was the second in a series of lectures titled “The Science of Being Human.”
While at Cal Tech, Round studied microbes in the human body that do not illicit reactions. She said as a trained immunologist, this baffled and intrigued her because she had been taught that the human body is programmed to recognize foreign entities and get rid of them, and yet there are more than 1 million non-human genes. She wondered why the human body tolerates these bacteria and how the bacteria function.
Round is now discovering the answers to these questions. Her research involves raising germ-free mice in a sterile environment. A single isolated microorganism, or “bug,” is then introduced, reducing the chances of autoimmune deficiency diseases, such as multiple sclerosis and inflammatory bowel disease.
Round’s ultimate goal is to use these microorganisms to treat such ailments in humans.
“Wouldn’t it be something if, instead of some nasty drug, you could just take this one little natural bug that would cure you?” she asked.
Everyone might not be comfortable with the thought of putting little living creatures into their bodies, but Round’s research does not stop there.
“Once we know which organism can prevent a certain disease, we can analyze specific molecules,” Round said. “Once the molecule is found we can try to turn it into therapy. People would usually rather take a little pill instead of a bunch of bacteria.”
Targeting ailments with specific molecules has long-term impacts in other areas of the body, Round said.
Antibiotics are non-discriminatory and kill many of the beneficial bacteria in addition to the harmful ones, and much of the damage can be permanent. Studies show the more antibiotic courses a person goes through — particularly early in life — the more likely they are to develop autoimmune diseases later.
The lack of these beneficial bacteria can cause other problems as well. The germ-free mice in Round’s laboratory studies had smaller livers, higher cholesterol levels, fewer immune cells and increased susceptibility to disease in general than the normal mice. The germ-free specimens were also less anxious and more likely to wander in uncertain environments, which Round said is not a good thing if you are a field mouse at the bottom of the food chain.
Julie Lewis and her family have attended both lectures in the series so far, and they plan on going to all of them.
“It’s an amazing series, covering so many different aspects,” she said. “When you think about what it means to be human, you don’t usually think of bacteria. And for every single human cell, 10 or more bacteria. They’re such an integral part of who we are. We’re each our own little colony.”
Round hoped there was just one thing audiences took away from her lecture, it was that bacteria are good.
“Well, most of them,” she said. “I’m not saying not to wash your hands after you use the bathroom. But the more diverse the organisms in your body are, and the more of them you have, the healthier you tend to be. So stop taking so many antibiotics.”
The next two lectures in the “Science of Being Human” series will be held on March 21 and April 11, both at 7 p.m.