UBC Research Unveils Link Between Early-Life Antibiotics and Allergies

Scientists at the University of British Columbia reveal a groundbreaking discovery about the role of gut bacteria in the development of lifelong allergies due to early-life antibiotic use, opening doors for new treatment approaches.

In a pioneering study, researchers at the University of British Columbia (UBC) have identified how the administration of antibiotics in newborns can lead to lifelong respiratory allergies. Published in the Journal of Allergy and Clinical Immunology, the UBC biomedical engineering and medical genetics team has shed light on the crucial role of gut bacteria in shaping our immune systems from the earliest days of life.

The study shows the first-ever cascade of events that explain why newborns given antibiotics are more prone to allergies and asthma. Understanding this process is a significant step toward discovering new methods for prevention and treatment.

“Our research finally shows how the gut bacteria and antibiotics shape a newborn’s immune system to make them more prone to allergies,” Kelly McNagny, senior author and professor at UBC’s School of Biomedical Engineering (SBME) and the Department of Medical Genetics, said in a news release.

Antibiotics given to combat infections in infants can reduce certain beneficial bacteria in the gut. These bacteria are essential for producing butyrate, a compound that halts allergy-inducing processes. Previous work by McNagny’s lab showed that fewer butyrate-producing bacteria increase susceptibility to allergies, which can be mitigated by administering butyrate early in life.

Examining this phenomenon in mice, the researchers found that those with depleted gut bacteria who didn’t receive butyrate supplements developed twice as many ILC2 immune cells. These cells are key players in allergy development and guide white blood cells to produce abundant antibodies, making the immune system hypersensitive to harmless substances like pollen or pet dander.

“When you see something like this, it really changes the way you think about chronic disease. This is a well-sculpted pathway that can have lasting consequences on susceptibility to chronic disease as an adult,” McNagny added.

The study reveals that butyrate must be administered within a narrow window shortly after birth to prevent the proliferation of ILC2s. Missing this window allows the cascade of immune responses to develop fully, establishing a lifelong predisposition to allergies.

The breakthrough doesn’t just end with understanding this early-life process. The researchers are now exploring how to intervene even after the critical window has passed.

“We can now detect when a patient is on the verge of developing lifelong allergies, simply by the increase in ILC2s,” said Ahmed Kabil, first author and doctoral candidate at SBME, in the news release. “And we can potentially target those cell types instead of relying on supplementation with butyrate, which only works early in life.”

Current allergy treatments like antihistamines provide symptomatic relief but do not address the underlying immune mechanisms. This new understanding offers a pathway to more effective, long-term solutions and could potentially shift the landscape of how allergies are managed or even prevented.

As researchers continue to explore this promising avenue, the hope is that future treatments will better target the cells and mechanisms that create this hypersensitive immune response, offering a brighter outlook for those prone to allergies.

The findings not only provide significant insight into the root causes of allergies but also open up numerous possibilities for innovative treatments and preventive strategies moving forward.