Researchers at the University of Chicago, Argonne National Laboratory, in collaboration with the University of Naples Federico II, in Italy, have shown that treating cow’s milk-intolerant infants with a probiotic supplement, was successful in reversing the milk allergy. When the gut microflora collected from these now-milk-tolerant infants was compared to the gut bacteria of infants with the milk allergy, the researchers found significant differences.
Children given the probiotic showed higher levels of bacterial strains known to produce short-chain fatty acids, such a butyrate; a compound known to promote intestinal health. The results were published in The International Society for Microbial Ecology (ISME) Journal. Supplementation with bacterial strains that promote food tolerance could become a useful treatment for infants with food allergies.
It’s estimated that the incidence of food allergies in children living in developed countries, has risen by as much as 20 percent in the last 10 years. One of the most common food allergies among infants is cow’s milk intolerance, which affects as many as 3 percent of children worldwide.
A multitude of different factors in our modern environment – including formula feeding, caesarean birth, limited exposure to infectious diseases, diets consisting of low-fiber and high-fat, and overuse of antibiotics – have been blamed for altering the symbiotic relationship between ourselves and the bacteria that live within our gut. It’s believed that disruption of the gut microflora – known as dysbiosis – can cause allergies in those individuals who also carry a predisposition.
Previous research conducted by Roberto Berni Canani – a collaborator on the current study – and his colleagues at the University of Naples, found that feeding a formula containing the milk protein casein to infants with cow’s milk intolerance, greatly increased the development of tolerance when the formula was combined with a probiotic containing Lactobacillus rhamnosus GG (LGG) bacteria. These infants had a better chance of developing milk tolerance, compared to children who were not provided with the probiotic supplement.
According to Cathryn Nagler, Ph.D, a Bunning Food Allergy Professor at the University of Chicago, and principal investigator of the study, “Mouse model work from our laboratory published last year, identified a common class of mucus-associated gut bacteria that play a critical role in regulating the access of dietary allergens to the bloodstream. This suggests a novel mechanism by which commensal bacteria regulate allergic responses to food.”
Nagler and her colleagues analyzed the DNA sequence of bacteria isolated from stool samples collected from three infant groups: healthy subjects, subjects who were given the LGG enriched probiotic formula and subjects who were fed conventional formula without the probiotics. This analysis was done in an effort to determine whether the probiotic was able to change the gut bacterial composition, and induce tolerance of cow’s milk.
The bacterial microbiome of infants with the allergy significantly deviated from the bacterial strains found in healthy individuals. This finding suggests that gut microflora play a role in the development of food allergies. Infants who developed a tolerance to cow’s milk following feeding with the LGG probiotic formula, had a higher number of butyrate-producing bacteria, compared to infants fed the non-probiotic formula. This result provided compelling evidence that specific beneficial bacterial strains – such as Blautia and Coprococcus – are important in the acquisition of food tolerance.
Jack Gilbert, Ph.D, associate professor in the Department of Ecology & Evolution at the University of Chicago, group leader for microbial ecology at Argonne National Laboratory and co-author of the study commented, “The ability to identify bacterial strains that could be used as novel therapeutics for treating food allergies is a fundamental advance. Translating these findings into clinical treatments is our next goal, and one that is now possible through the new FARE Clinical Network center here at the University of Chicago.”
- Probiotic formula reverses cow’s milk allergies by changing gut bacteria of infants – http://medicalxpress.com/news/2015-09-probiotic-formula-reverses-cow-allergies.html
- Canani, R., Sangwan, N., Stefka, A., Nocerino, R., Paparo, L., Aitoro, R., Calignano, A., Khan, A., Gilbert, A., and Nagler, C. (2015). Lactobacillus rhamnosus GG-supplemented formula expands butyrate-producing bacterial strains in food allergic infants.ISME J.