There’s an adage that “a little dirt is good for you,” and a new study from Linköping University in Sweden suggests something similar about preventing asthma and allergies in children. Children who develop asthma or allergies have an altered immune response to intestinal bacteria in their mucous membranes even when they’re infants. Linköping University’s new study also suggests that the mother’s immune system can play a part in preventing allergies and asthma in children.
"The results [of the study] confirm our idea that the intestinal flora (also known as the 'intestinal microbiota') early in life plays a role during the development of allergy symptoms. We believe that diversity among the bacteria contributes to strengthening the immune defense in the mucous membranes. In our new study we saw differences in the immune response against intestinal bacteria in children who subsequently developed allergy symptoms," says Maria Jenmalm, an author of the study and professor of experimental allergology at Linköping University.
What Researchers Learned about Preventing Allergies & Asthma in Children
The researchers in the study investigated the children’s mucous membranes’ immune defense against various bacteria. Mucous membranes deal with large amounts of bacteria and viruses, and there are high concentrations of “IgA antibodies” to protect the body from harm. These antibodies bind to dangerous microorganisms and stop them from entering the body.
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| Asthma and allergies affect many children today. Source: cdc.gov |
The study then analyzed stool samples from infants at one month and then again at 12 months. They discovered that the first year of life had an important influence on the immune response later in life. "Children who subsequently developed allergies had a lower fraction of IgA antibodies bound to their intestinal bacteria when aged 12 months than children who did not. This difference may suggest that the barrier function of the mucous membranes is less effective in children who later develop allergies. The lack of IgA was particularly noticeable in children who developed asthma during the first seven years of life," said Maria Jenmalm.
The Results
Even at one-month old, there were clear differences between healthy children and children who would later develop asthma or allergies. By looking at the composition of bacteria in stool samples and studying the differences in the IgA antibodies between the children, it was evident that the mother’s immune response was a clear factor in preventing significant childhood asthma and allergies that persisted later in life. Those children who had intestinal diversity were less likely to have asthma or allergies when they grew up.
There is much more research to be done on how the mother’s immune response contributes to the child’s. This study is an important step in noting that intestinal diversity in infants is a factor in preventing asthma and allergies in children.
