Stories about: microbiome

Our intestinal microbiome influences metabolism — through the immune system

microbiome metabolism concept - in Drosophila. In absence of intestinal bacteria to modulate metabolism, flies develop fat droplets.

Research tells us that the “good” bacteria that inhabit our intestines help to regulate our metabolism. A new study in fruit flies shows one of the ways in which these commensal microbes keep us metabolically fit.

The findings, published today in Cell Metabolism, suggest that innate immune pathways, our first line of defense against bacterial infection, have a side job that’s equally important.

The intestine’s digestive cells use an innate immune pathway to respond to harmful bacteria by producing antimicrobial peptides. But other intestinal cells, enteroendocrine cells, use the same pathway, known as IMD, to respond to “good” bacteria — by fine-tuning body metabolism to diet and intestinal conditions.

“What’s most interesting to me is that some innate immune pathways aren’t just for innate immunity,” says Paula Watnick, MD, PhD, of the Division of Infectious Diseases at Boston Children’s Hospital. “Innate immune pathways are also listening to the ‘good’ bacteria – and responding metabolically.”

Read Full Story | Leave a Comment

Could poop transplants treat peanut allergy? A clinical trial begins

FMT peanut allergy

Increasing evidence supports the idea that the bacteria living in our intestines early in life help shape our immune systems. Factors like cesarean birth, early antibiotics, having pets, number of siblings and formula feeding (rather than breastfeeding) may affect our microbial makeup, or microbiota, and may also affect our likelihood of developing allergies.

Could giving an allergic person the microbiota of a non-allergic person prevent allergic reactions? In a new clinical trial, a team led by Rima Rachid, MD, of Boston Children’s Division of Allergy and Immunology, is testing this idea in adults with severe peanut allergies. The microbiota will be delivered through fecal transplants — in the form of frozen, encapsulated poop pills.

Read Full Story | Leave a Comment

Which bacteria in the gut microbiome are really influencing disease?

investigating the 'influencers' in the gut microbiome

Over the last decade, multiple studies have examined possible links between groups of microbes and the presence or absence of multiple diseases, including diabetes, multiple sclerosis, autism and inflammatory bowel disease. But on an individual basis, it’s been unclear which microbes are innocent bystanders, mere markers of disease, and which are active agents, causing harm or providing protection.

Scientists from Harvard Medical School and Boston Children’s Hospital have now designed and successfully used a method to tease out cause-and-effect relationships within the microbiome. Their work, conducted in mice, was described Dec. 6 in Nature.

Read Full Story | Leave a Comment

Food for thought: How your microbiome celebrates Thanksgiving

Image of microbiome superimposed over a Thanksgiving turkeySeth Rakoff-Nahoum, MD, PhD, a Boston Children’s Hospital physician-scientist who does infectious disease research and is taking an evolutionary approach to understanding the human microbiome and its effect on health, offers us some insight into what’s happening to the bugs in our gut as a result of the Thanksgiving meal. 

Q: Does the traditional American Thanksgiving meal affect the human microbiome?

A: Anything you put in your body has the potential to affect your microbiome, and Thanksgiving dinner is no different.

Read Full Story | Leave a Comment

Immune gene guards against type 1 diabetes by changing the microbiome. Do early antibiotics undercut its effects?

type 1 diabetes microbiome antibiotics

The health of our immune system is increasingly linked with the health of our intestinal bacteria. A mouse study from Harvard Medical School now hammers this home for autoimmune disorders, in which the body attacks its own cells. It looked specifically at type 1 diabetes, in which the body destroys the cells that make insulin.

Scientists have long known that the human leukocyte antigen (HLA) complex of proteins (also known as the major histocompatibility complex, or MHC) keep autoimmune responses in check. Certain common variants of the HLA/MHC genes are known to protect against a type 1 diabetes. But until now, how these genes prevent autoimmune reactions has been a mystery.

Read Full Story | Leave a Comment

Another microbiome perspective: The host holds the leash

Abstract depiction of the microbiome

Most scientists and clinicians accept that the human microbiome impacts a person’s nutrition, immune system function, physical health and perhaps even mental illness, but exactly how or why is not well understood. Now, taking an evolutionary approach, a Boston Children’s Hospital infectious disease researcher suggests the host may play a more active role in controlling the microbiome than previously appreciated.

“I think we need to re-evaluate the way in which we think about the microbiome,” says Seth Rakoff-Nahoum, MD, PhD, a physician-scientist at Boston Children’s in the Divisions of Infectious Diseases and Gastroenterology, whose perspective was published today in Nature.

Read Full Story | Leave a Comment

Could fecal transplants heal Crohn’s and colitis in children? Two trials are set to find out

two trials test fecal transplant in Crohn's and colitis in children

Could an exciting potential treatment for inflammatory bowel disease (IBD) be found in the gastrointestinal tract itself? That’s the theory behind a pair of new studies by Stacy A. Kahn, MD, which will investigate the potential role of fecal microbial transplant (FMT) in the treatment of Crohn’s disease and ulcerative colitis in children.

In IBD, the immune system attacks healthy cells in the digestive tract, triggering symptoms such as abdominal pain, fatigue, poor growth and bloody diarrhea. Children with IBD can also experience problems elsewhere in the body, including joint pain, liver disorders and eye inflammation.

Known colloquially as the “poop pill,” or “stool transplant,” FMT harnesses growing knowledge about the gut microbiota, the collection of bacteria and other microbes that populate our GI tract.

Read Full Story | Leave a Comment

News Notes: Pediatric science roundup

A quick look at recent research Vector finds noteworthy.

Tracking infants’ microbiomes

cute microbes-shutterstock_317080235-croppedMicrobiome studies are blooming as rapidly as bacteria in an immunocompromised host. But few studies have been done in children, whose microbiomes are actively forming and vulnerable to outside influences. Two studies in Science Translational Medicine on June 15 tracked infants’ gut microbiomes prospectively over time. The first, led by researchers at the Broad Institute and Massachusetts General Hospital, analyzed DNA from monthly stool samples from 39 Finnish infants, starting at 2 months of age. Over the next three years, 20 of the children received at least one course of antibiotics. Those who were repeatedly dosed had fewer “good” bacteria, including microbes important in training the immune system. Overall, their microbiomes were less diverse and less stable, and their gut microbes had more antibiotic resistance genes, some of which lingered even after antibiotic treatment. Delivery mode (cesarean vs. vaginal) also affected microbial diversity. A second study at NYU Langone Medical Center tracked 43 U.S. infants for two years and similarly found disturbances in microbiome development associated with antibiotic treatment, delivery by cesarean section and formula feeding versus breastfeeding.

Read Full Story | Leave a Comment

Microbiome therapeutics: 6 takeaways from a MassBio panel

microbiome therapeuticsSeeing the surprising success of “poop pills” in gastrointestinal C. difficile infection, pharma companies and startups are embracing the microbiome as a new therapeutic target for an astonishing range of maladies. To learn what pioneering companies in the space are thinking about the hope and the hype, Vector recently attended a panel on microbiome therapeutics at the MassBio Annual Meeting.

Read Full Story | Leave a Comment

Probing the link between autism, GI disorders and the microbiome

autism microbiome
(Dubova/Shutterstock)

Sonia A. Ballal is an attending physician in the Division of Gastroenterology, Hepatology and Nutrition at Boston Children’s Hospital.

Eleven-year-old Lyle has autism and doesn’t speak, but his mother is used to reading his nonverbal cues. He prefers a routine, but has always been a generally cheerful child who enjoys school and playing with his little sister.

Several weeks before I met Lyle (not his real name), his mother observed a dramatic shift. He was agitated, at times hitting his head against the wall, not receiving his typical sunny reports from school.

Read Full Story | Leave a Comment