Revolutionizing Pediatric CMA Treatment: Exploring the Synergy Between Gut Microbiome and Oral Immunotherapy

 

Approximately two to three percent of infants are affected with cow's milk allergy (CMA), which is one of the most prevalent food allergies in children. It happens when cow's milk proteins are incorrectly recognized by the immune system as dangerous invaders, leading to an allergic reaction. From minor symptoms like hives and digestive issues to severe ones like anaphylaxis, symptoms can vary widely. Strict dairy product avoidance is necessary for many families to manage CMA, which can be difficult and restrict food options. On the other hand, new findings about the function of gut bacteria in fostering immunological tolerance and oral immunotherapy (OIT) provide hope for a more long-lasting treatment.

The gut microbiota, which is made up of trillions of bacteria, lives in the human gut. These microbes not merely inhabitants of our intestines. They are also actively involved in immune system regulation. The gut microbiome profile of children with cow’s milk allergy (CMA) is very different from that of those without allergies. Their immune system may respond negatively to the proteins in cow's milk as a result of this imbalance, which could result in allergic responses.

Treatment for desensitizing the immune system to allergens is called oral immunotherapy, or OIT. This entails giving the allergic person progressively higher doses of milk protein in order to treat CMA. As time passes, the immune system becomes accustomed to handling these proteins without producing a significant allergic reaction. On the other hand, long-term tolerance maintenance might be difficult, and OIT results can differ widely. This is where the role of the gut bacteria is revealed. Successful OIT outcomes were linked to particular alterations in the gut flora. Comparing children who responded poorly to OIT with those who developed a tolerance to milk, the former group displayed a greater diversity of gut bacteria and a greater abundance of beneficial microbial species.

Pro- and anti-inflammatory cytokine balance is regulated by the gut microbiota, which in turn affects the immune system. This equilibrium is essential for preserving a robust immune system and delaying the development of lactose intolerance symptoms. The epithelial barrier, which divides the gut lumen from the bloodstream, is kept intact in part by the gut bacteria. This barrier's ability to stop toxins and allergens from entering the bloodstream lowers the chance of developing lactose intolerance. The expression of major histocompatibility complex (MHC) molecules on antigen-presenting cells is regulated by the gut microbiota, which in turn affects antigen presentation. This is a vital process that the immune system uses to identify and get rid of allergens. Tregs, or regulatory T cells, are essential for preserving immunological tolerance and their function is largely regulated by the gut microbiota. To stop lactose intolerance symptoms from developing, tregs aid in the suppression of pro-inflammatory T cell activity.

The study examined several clinical characteristics and gut bacterial species linked to good treatment outcomes in order to comprehend why the medication was effective for some children but not for others. Successful OIT was less common among children receiving medication for asthma or eczema, as well as in those with initially greater levels of milk-protein antibodies. On the other hand, increased success rates were associated with the presence of Bifidobacterium, a genus of beneficial bacteria belonging to the Bifidobacteriaceae family. CMA has health hazards and is a continual source of anxiety in addition to being a dietary limitation. We can enhance OIT results and progress toward more potent, long-lasting food allergy treatments by leveraging the power of gut microbiota.

REFERENCE:

Shibata, Ryohei, Naoka Itoh, Yumiko Nakanishi, Tamotsu Kato, Wataru Suda, Mizuho Nagao, Tsutomu Iwata et al. "Gut microbiota and fecal metabolites in sustained unresponsiveness by oral immunotherapy in school-age children with cow's milk allergy." Allergology International 73, no. 1 (2024): 126-136.

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2.Nutrients : https://www.mdpi.com/2072-6643/16/7/1002