Ed Yong, an award-winning science writer for The Atlantic, and Jack Gilbert, a professor of surgery at the University of Chicago, discussed how microbes —communities of microscopic organisms that live on or in people, plants, soil, oceans and the atmosphere — affect life forms on Earth, and how they can be manipulated to improve human health during a session titled “Invisible Influence: Microbiomes in the World” Monday evening at the Rackham Amphitheater.
The session was part of the Michigan Meeting on Microbial Communities, a conference organized by the Center for Microbial Systems, which promotes the study of microbiology at the University. The conference, titled “Unseen Partners: Manipulating Microbial Communities that Support Life on Earth,” continues until Wednesday and features speakers with many different areas of expertise in microbes.
Last week, the White House Office of Science and Technology Policy announced the National Microbial Initiative, an initiative to advocate the study of microbiomes. Dysfunctional microbiomes have been linked to many human diseases, disruptions in ecosystems and reduced agricultural productivity.
Microbes — usually bacteria, fungi, viruses or protozoa — refer to any organism that is too small to be seen with naked eye. Some microbes are harmful for human health, as they cause diseases such as the common cold, chickenpox, malaria and pneumonia, but others are beneficial, such as the bacteria that live in intestines that help with absorbing nutrients from the processed food, according to the National Institutues of Health.
Yong began his talk by commenting on how ubiquitous and important microbes are for people and ecosystems, though it might be unsettling and unnerving to think the human body contains multitudes of microbes. Yong mentioned that many animals rely on microbes for essential tasks, such as digesting food.
In spite of how important microbiomes are for human health, Yong said the current understanding of microbes is insufficient partly due their complicated nature. For example, in some cases it is not certain whether the change in the microbiome causes a disease or if a disease results in a microbiome change.
Yong additionally discussed the inefficiency of probiotics to illustrate the complicated nature of microbiomes. According to Yong, the bacteria in probiotics might be too domesticated compared to the native gut bacteria to survive once they are in the digestive system, meaning any probiotic model may not clearly demonstrate all of the properties of natural microbiomes.
“The problem with probiotics … is that they contain highly domesticated bacteria,” Yong said. “The benefits (of probiotics) are unclear at best.”
On the other hand, Yong said transplanting more than a few specific microbial species might lead to more successful results. Fecal transplants deliver stool samples from healthy donors to ill patients to change the microbiome in the patient’s digestive tract, according to Johns Hopkins Medicine. Currently, this procedure is used to treat recurrent inflammation in the large intestine caused by a bacterial species called Clostridium difficile.
“This idea of giving a community of microbes, I think, makes a lot of sense when thinking about other applications,” Yong said. “One of the most successful attempts involve exactly that … (Fecal transplant) is quite like an ecosystem transplant.”
Gilbert emphasized the importance of microbiomes in a medical setting, saying that studying the microbiome in individual patients is necessary for precision medicine, in addition to studying the human genome.
“Why doesn’t genetics give us the whole answer?” Gilbert said. “Because we need the human genome … but we need microbial genome as well.”
Gilbert further discussed how manipulating the microbiome can be useful for treating and curing many human diseases, such as allergies. Gilbert discussed, for instance, Amish children, who grow up on farms and usually do not develop asthma or allergies due to their exposure to certain microbes during their youth.
Gilbert also discussed other health issues such as obesity and cancer from a microbiome perspective, mentioning that changing the microbiome can be an approach to fight such health crises.
“We are now working very exclusively to find way to use the microbiome … to make the immune system fight cancer,” Gilbert said. “There are many ways we can harbor microbiome therapies for treating diseases.”
LSA sophomore John Hartert said he attended the session and a couple of talks during the day because he is interested in microbial ecology. Hartert particularly found the ubiquitous and impactful nature of the microbiome interesting.
“I was really interested in how expansive the effects of the microbiome is,” Hartert said.