Further Insights into the Gut Microbiota of Cow’s Milk Allergic Infants: Analysis of Microbial Functionality and Its Correlation with Three Fecal Biomarkers

Cow’s milk allergy (CMA) is one of the most prevalent food allergies in children. Several studies have demonstrated that gut microbiota influences the acquisition of oral tolerance to food antigens at initial stages of life. Changes in the gut microbiota composition and/or functionality (i.e., dysbiosis) have been linked to inadequate immune system regulation and the emergence of pathologies. Moreover, omic sciences have become an essential tool for the analysis of the gut microbiota. On the other hand, the use of fecal biomarkers for the diagnosis of CMA has recently been reviewed, with fecal calprotectin, α-1 antitrypsin, and lactoferrin being the most relevant. This study aimed at evaluating functional changes in the gut microbiota in the feces of cow’s milk allergic infants (AI) compared to control infants (CI) by metagenomic shotgun sequencing and at correlating these findings with the levels of fecal biomarkers (α-1 antitrypsin, lactoferrin, and calprotectin) by an integrative approach. We have observed differences between AI and CI groups in terms of fecal protein levels and metagenomic analysis. Our findings suggest that AI have altered glycerophospholipid metabolism as well as higher levels of lactoferrin and calprotectin that could be explained by their allergic status.This research was funded by Instituto de Salud Carlos III (PI17/01087 and PI20/01366) and Fundación Sociedad Española de Alergia e Inmunología Clínica (FSEAIC_2016). It was co-funded by the European Regional Development Fund “Investing in your future” for the thematic network and co-operative research centers ARADyAL RD16/0006/0015 and RD16/0006/0026. T.B-T is supported by FPI-CEU predoctoral fellowship. D.B. acknowledges financial support from Instituto de Salud Carlos III (PI19/00044)

{IgE}-mediated fish allergy in pediatric age: Does canned tuna have a chance for tolerance?

N/

Variability of the ISAC 112 technique in the calibrator sample.

<p>Coefficient of Variation (CV) obtained to allergens of calibration curve. The results are the mean CV of 10 determinations intra- and inter-assay, and 2 determinations inter-laboratory and inter-batches of the calibrator sample.</p

Accuracy of ISAC 112.

<p>Results obtained for the allergens that form the calibration curve with the intra-assay, inter-assay, inter-laboratory and inter-batch determinations performed with the calibrator CTR02, composed by chimeric antibodies. Expected ISU results are depicted by red line and the observed mean ISU results are depicted by red +++. Student T test was used for statistical analysis.</p

Intraclass Correlation Coefficient (ICC) of ISAC 112 results obtained from 10 determinations of 4 sera intra- and inter-assay and two determinations of 20 sera inter-laboratory and inter-batch.

*<p>The ICC could not be calculated as all the determinations were equal to 0 ISU.</p>†<p>Allergens detected by the calibration curve.</p><p>ICC ranges: very good (>0.9), good (0.71–0.90), moderate (0.51–0.70), mediocre (0.31–0.50) and poor (<0.30). Underlined are showed ICC values below 0.7.</p