How microbes influence the development of the infant immune system

When infants leave their mostly sterile home in the uterus during birth, they are rapidly colonized with microbes from the surrounding environment, the majority of which takes place in the intestinal tract. This is a critical time for the newborn’s immune system, as it learns to separate friend from foe.

Research has shown that “crosstalk” between these early microbe colonizers and the immune cells in intestines plays a key role in developing a well-functioning immune system, but until now the specific process by which that occurs had not yet been defined.

An MGH research team found these early interactions between microbes and immune cells are communicated to the thymus – an organ responsible for creating specialized immune cells early in life – through specialized cells that are imprinted with microbial signatures in the intestine. The cells then travel up to the thymus, which is located just under the breastbone between the lungs.

If this signaling process goes awry, newly formed immune cells may start to target helpful microbes instead of harmful ones, which could disrupt the balance of the gut microbiome.

An unbalanced microbiome is believed to increase the risk of developing allergies, asthma and autoimmune disorders such as celiac disease and inflammatory bowel disease later in life.

A better understanding of this process could lead to new strategies that promote a healthier relationship between intestinal cells and the microbiome. The study was led by Nitya Jain, PhD, and Alessio Fasano, MD, both of the Mucosal Immunology and Biology Research Center.

A cool new way to reduce fat

The MGH research team that invented a process called Coolsculpting – a popular non-surgical method for reducing fat under the skin – is now developing a new technology that can reduce fat almost anywhere in the body using a safe, injectable ice solution, or slurry.

Coolsculpting, while highly effective, is limited by the amount of fat that can be removed per session and is not practical for reaching deeply seated fat in the body. The slurry injection, by contrast, can target and remove fat tissue at any site that can be accessed by a needle or catheter.

One key benefit of the slurry technique is that it is specifically designed to target fat and does not damage any surrounding organ or muscle tissues. In a study in pig models, the researchers reported a 55 percent reduction in fat thickness with no damage to skin or muscle at the injection site, and no systemic side effects or abnormalities.

More research and safety testing will have to be done before the process is approved for use in humans, but the research team is optimistic it could provide a significant upgrade in fat removal technology if approved.

“With this new technique, the doctor can do a simple injection that takes less than a minute, the patient can go home, and then the fat gradually disappears,” says Lilit Garibyan, MD, PhD, an investigator in the Wellman Center for Photomedicine and co-author of the study along with center director Rox Anderson, MD.