Maternal gut microbiota transmission and early-life colonization patterns influence infant CMPA risk.

The establishment of gut microbiota in early life represents a critical window for immune system development and the prevention of cow's milk protein allergy (CMPA). While maternal influence on infant gut colonization is well-documented, the specific relationship between maternal-infant microbiota patterns and CMPA development remains poorly understood. In this study, we analyzed 106 fecal samples from maternal-infant pairs, including 16 complete triads (maternal, newborn, and 3-month infant samples), using 16S rRNA sequencing to identify key bacterial markers associated with CMPA risk. Our findings revealed distinct temporal colonization patterns, with initial Staphylococcus dominance in newborns shifting to Bifidobacterium predominance by three months, a trend particularly pronounced in infants with CMPA. Breastfeeding emerged as a significant factor influencing microbial development, with exclusively breastfed infants showing a lower risk of CMPA. Phylogenetic analysis confirmed the vertical transmission of Staphylococcus, Bifidobacterium (such as Bifidobacterium longum and Bifidobacterium breve), Blautia, and Enterococcus between mothers and infants. Furthermore, functional pathway analysis highlighted the role of amino acid metabolism in immune system development, suggesting potential mechanisms through which early microbiota may influence CMPA risk. These findings provide new insights into the interplay between maternal-infant microbiota transmission, feeding practices, and CMPA development, offering potential avenues for early intervention and prevention strategies.

Importance: The establishment of intestinal flora in early life is essential for the health and development of living organisms. At birth, the newborn has already established an initial gut microbiota with distinct characteristics. The link between the composition of the gut microbiota and immune-related symptoms such as allergies is a hot topic, and it starts to show up early in life. It is helpful to study the characteristics and developing rules of early life intestinal flora by interpreting the characteristics of early life flora, the relationship with maternal flora, the development law with age, and the correlation with feeding patterns and so on. In this study, we presented and compared the gut microbiota of newborns, 3-month-old infants, and their mothers to provide a preliminary understanding of the establishment of early life microbiota and its correlation with allergies.