Blog editor shift

This is partly a temporary good-bye and partly an introduction to Wayne Drash. Wayne will be filling in for Quinn Eastman, who has been the main editor of Lab Land. Wayne is a capable writer. He spent 24 years at CNN, most recently within its health unit. He won an Emmy with Sanjay Gupta for a documentary about the separation surgery of two boys conjoined at the head. Wayne plans to continue writing about biomedical research at Read more

Some types of intestinal bacteria protect the liver

Certain types of intestinal bacteria can help protect the liver from injuries such as alcohol or acetaminophen overdose. Emory research establishes an important Read more

Can blood from coronavirus survivors save the lives of others?

Donated blood from COVID-19 survivors could be an effective treatment in helping others fight the illness – and should be tested more broadly to see if it can “change the course of this pandemic,” two Emory pathologists say. The idea of using a component of survivors’ donated blood, or “convalescent plasma,” is that antibodies from patients who have recovered can be used in other people to help them defend against coronavirus. Emory pathologists John Roback, MD, Read more

Andrew Gewirtz

Breaking the rules: flagellin vs rotavirus

Flagellin is a bacterial protein that activates the innate immune system. Its name comes from flagella, the whips many bacteria use to propel themselves.

On Thursday, a team of researchers led by immunologist Andrew Gewirtz reported in Science that treatment with flagellin can prevent or cure rotavirus infection in animals. Rotavirus infection is one of the most common causes of severe diarrhea and is a major cause of death for children in developing countries.

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Andrew Gewirtz, PhD

Gewirtz’s lab is now at Georgia State, but he and his colleagues initiated this research while at Emory and several co-authors are affliliated with Emory, including immunologist Ifor Williams.

These findings are remarkable for several reasons. One is: give the immune system something from bacteria, and it’s better at fighting a virus? As Gewirtz says in a GSU news release: “It’s analogous to equipping an NFL defense with baseball bats. Blatant violation of all the rules but yet, at least in this case, very effective.”

For me, what was most surprising about this paper was that treatment with flagellin, or immune signaling proteins activated by flagellin, can get mice with severely impaired immune systems – no T cells or B cells at all — to evict rotavirus. These are mice that have to be reared under special conditions because they are vulnerable to other infections. Interferons, well-known antiviral signaling molecules, are also not involved in resisting or evicting rotavirus infection, the researchers found. Read more

Posted on by Quinn Eastman in Immunology Leave a comment

How intestinal bacteria influence appetite, metabolism

Pathologist Andrew Gewirtz and his colleagues have been getting some welldeserved attention for their research on intestinal bacteria and obesity.

Briefly, they found that increased appetite and insulin resistance can be transferred from one mouse to another via intestinal bacteria. The results were published online by Science magazine.

Previous research indicated intestinal bacteria could modify absorption of calories, but Gewirtz and his colleagues showed that they influence appetite and metabolism (in mice)

“It has been assumed that the obesity epidemic in the developed world is driven by an increasingly sedentary lifestyle and the abundance of low-cost high-calorie foods,” Gewirtz says. “However, our results suggest that excess caloric consumption is not only a result of undisciplined eating but that intestinal bacteria contribute to changes in appetite and metabolism.”

A related report in Nature illustrates how “next generation” gene sequencing is driving large advances in our understanding of all the things the bacteria in our intestines do to us.

Gewirtz’s laboratory’s discovery grew out of their study of mice with an altered immune system. The mice were engineered to lack a gene, Toll-like receptor 5 (TLR5), which helps cells sense the presence of bacteria.

Read more

Posted on by Quinn Eastman in Immunology Leave a comment