Published online: January 12, 2018
The gut microbiome plays an important role in human health. Infancy is a critical period for the colonization of the gut microbiome, which affects host immune development. Therefore, perturbation of the infant gut microbiome can shape the development of the immune system and link to the risk of allergic disease including atopic dermatitis. Several factors can affect colonization of the gut microbiome, and the feeding type is the greatest factor on the colonization of the gut microbiome in early life. However, studies on the complex relationship between the gut microbiome and atopic dermatitis according to feeding type in early life are limited.
In a recently published research article in The Journal of Allergy & Clinical Immunology (JACI), Hong and colleagues investigated the composition and functional differences of gut microbiomes between healthy infants and infants with atopic dermatitis according to feeding type. They analyzed the gut microbiomes of 129 (6-month-old) infants in the longitudinal Cohort for Childhood Origin of Asthma and Allergic Diseases (COCOA) birth cohort study with measured clinical characteristics.
The authors found that the gut microbiomes of 6-month-old infants were different by feeding type, even among infants with the same atopic dermatitis status. The gut microbiomes were divided into Bifidobacterium-dominated microbiomes and Escherichia/Veillonella-dominated microbiomes in both the breast milk-fed and mixed milk-fed infants. Although the composition of gut microbiomes differed according to feeding type, there were no significant differences between healthy infants and infants with atopic dermatitis within each feeding type. However, the total bacterial amounts in gut microbiomes from healthy infants were higher than in those from infants with atopic dermatitis in all feeding types. Furthermore, the reduction of microbiome genes for oxidative phosphorylation, PI3K-Akt signaling, estrogen signaling, NOD-like receptor signaling, and antigen processing and presentation induced by reduced colonization of mucin-degrading bacteria was significantly associated with stunted immune-development in the atopic dermatitis infants compared to the healthy infants.
The obtained results suggest that the colonization of mucin-degrading bacteria and their contribution to innate immune development in the gut play a crucial role in infants with atopic dermatitis. In addition, they showed that the analysis of the gut microbiome in infants with atopic dermatitis should consider feeding type and the understanding of the gut microbiome role is more important than simple comparison of microbial members between healthy infants and infants with atopic dermatitis.
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.