Pediatrics & Therapeutics
Open Access

Infants Immune Tolerance and the Gut Microbiota

Joseph A Iocono^{* *}Correspondence: Joseph A Iocono, Department of Surgery, The University of Kentucky, Markey Cancer Center, Lexington, USA, Email:

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Description

Food Allergy (FA) and food allergies are pathologies related to exposure to food allergens. Immunoglobulin (Ig) E-mediated FA is now more common in youngsters, with prevalence rates ranging from 1 to 2.53% in the USA and Canada to 5.5% in Chile. Self-report studies have shown higher numbers, up to 25% in some areas. The most typical allergies, which vary depending on the nation and age group, include peanuts, walnuts, eggs, milk, fish, and soy. Vitamin D insufficiency, delayed exposure to food allergens, reduced exposure to microorganisms (as suggested by the hygiene hypothesis), and changes in the microbiota are all risk factors for the development of FA.

The group of bacteria that populate the intestine is referred to as the gut microbiota. Dysbiosis is the breakdown of the gut microbiota's equilibrium as a result of variations in their relative diversity and abundance. Children with FA have been found to have this disorder, and their gut microbiota profiles are different from those of children without FA. A increased relative abundance of Bacteroides and Alistipes has been identified, along with alterations brought on by probiotic supplementation, in the intestinal microbiota of people with food allergies that are caused by mechanisms other than IgE that are prevalent in around one-third of the population. As a result, changes in the microbiota would not be linked to IgE alone. The rigorous elimination of the allergen from the diet is the only currently available treatment for FA.

However, depending on the type and quantity of allergens implicated as well as the patient's age at the time of the diagnosis, this strategy may have an effect on the patient's nutritional status. Therefore, it is important to investigate novel therapeutics to help these individuals develop food-specific immune tolerance and minimize FA symptoms. Infants' immune systems are believed to be actively developing and being trained, rendering them predisposed to react to microbial pathogens and cause atopic reactions. The newborn's immune system depends on the mother's immunity, which is passed on through the placenta, exposure during birthing (the birth canal), and breastfeeding throughout neonatal life.

Numerous studies have indicated that nonhereditary factors may be more important for moulding the immune system and developing immunity during the first year of life, despite the fact that hereditary factors also influence the sort of immunological response that a baby may develop. For instance, 204 immunityrelated characteristics were defined in a recent study on twins, and it was discovered that 77% of them were significantly influenced by nonhereditary factors. Additionally, compared to what has been documented for adult immune cells, baby immune cells have been found to have considerable intraindividual heterogeneity. This finding emphasizes the importance of prenatal environmental exposure. The majorities of a newborn’s immune system’s components are developed but still have rudimentary functions.

In terms of cell types, neutrophils are seen to be enhanced in the fetus but decline to levels that will be predominant in adulthood a few days after delivery. Cytotoxic T lymphocytes also show reduced activity compared to adults, while monocytes and macrophages also show signs of immaturity. The concentration of immune cells in various age groups revealed a predominance of lymphocytes, platelets, and B cells that significantly decline with ageing, neutrophils and CD8+ T cells that rise in adulthood, and Natural Killer (NK) cells, which are a component of the innate immune response, that rise primarily in adolescence. Children's mononuclear cells have a diminished ability to release IL-12p70, which is essential for the polarization of Th1 cells. Children consequently exhibit an immune response that is primarily Th2.