Gut Microbiota Profile in Children with IgE-Mediated Cow's Milk Allergy and Cow's Milk Sensitization and Probiotic Intestinal Persistence Evaluation

Abstract

Food allergy (FA) and, in particular, IgE-mediated cow's milk allergy is associated with compositional and functional changes of gut microbiota. In this study, we compared the gut microbiota of cow's milk allergic (CMA) infants with that of cow's milk sensitized (CMS) infants and Healthy controls. The effect of the intake of a mixture of Bifidobacterium longum subsp. longum BB536, Bifidobacterium breve M-16V and Bifidobacterium longum subsp. infantis M-63 on gut microbiota modulation of CMA infants and probiotic persistence was also investigated. Gut microbiota of CMA infants resulted to be characterized by a dysbiotic status with a prevalence of some bacteria as Haemophilus, Klebsiella, Prevotella, Actinobacillus and Streptococcus. Among the three strains administered, B.longum subsp. infantis colonized the gastrointestinal tract and persisted in the gut microbiota of infants with CMA for 60 days. This colonization was associated with perturbations of the gut microbiota, specifically with the increase of Akkermansia and Ruminococcus. Multi-strain probiotic formulations can be studied for their persistence in the intestine by monitoring specific bacterial probes persistence and exploiting microbiota profiling modulation before the evaluation of their therapeutic effects.

Keywords: cow’s milk allergic (CMA); cow’s milk sensitized (CMS); gut microbiota profiling; probiotics; quantitative real-time PCR assays.

Figure 1

Median differences between B. breve, B. longum subsp. longum and B. longum subsp. infantis levels expressed as molecules/ul at T₀ for the three analyzed groups (* p < 0.05).

Figure 2

Median differences between B. breve, B. longum subsp. longum and B. longum subsp. infantis levels expressed as molecules/ul at each point of the time-course for the cow’s milk allergic (CMA) group.

Figure 3

Boxplots representing alpha-diversity computed by Observed, Chao1 and Shannon indexes in the three CMA, cow’s milk sensitized (CMS), and HEALTHY groups. Boxes represent the median, 25th and 75th percentiles calculated for CMA (blue), CMS (yellow), and HEALTHY (red) groups.

Figure 4

Boxplots representing alpha-diversity by Observed, Chao1 and Shannon indexes during the time-course for the CMA group. Boxes represent the median, 25th and 75th percentiles calculated for CMA group at T₀ (blue), T₁ (yellow), T₃ (red) and T₅ (purple). p-values are reported.

Figure 5

Operational Taxonomic Unit (OUT) distribution of the gut microbiota for the three groups’ comparison assessed by DeSeq2 test at genus level. The interquartile range is represented by the box and the line in the box is the median. The whiskers indicate the largest and the lowest data points, respectively, while the dots symbolize outliers. Only statistically significant OTUs (p < 0.05) are plotted.

Figure 6

OTU distribution of the gut microbiota during the time-course of the CMA group computed by DeSeq2 test at phylum level. The interquartile range is represented by the box and the line in the box is the median. The whiskers indicate the largest and the lowest data points, respectively, while the dots symbolize outliers. Only statistically significant OTUs (p < 0.05) are plotted.

Figure 7

OTU distribution of the gut microbiota during the time-course of the CMA group computed by DeSeq2 test at the genus level. The interquartile range is represented by the box and the line in the box is the median. The whiskers indicate the largest and the lowest data points, respectively, while the dots symbolize outliers. Only statistically significant OTUs (p < 0.05) are plotted.