Can microbial and dietary interventions in mother and child prevent asthma and allergy development?

Background

The maternal microbial environment during pregnancy, the pioneer microbiome provided to the child during vaginal delivery and the early postnatal gut and oral microbiota may crucially influence offspring immune programming and allergy and asthma development. Aims and work plan We aim to investigate whether:

1) Pre- and postnatal Lactobacillus reuteri and omega-3 polyunsaturated fatty acid supplementation can prevent allergy development via influences on maternal and child immunity, including at an epigenetic level (Intervention study 1).

2) Providing maternal vaginal and gut microbiota to neonates delivered by elective Caesarean section enhances gut and oral microbiota diversity during infancy and reduces allergy development (Intervention study 2).

We will perform two unique allergy and asthma prevention trials, in inter-disciplinary collaborative efforts between experts in immunology and metabolomics, system biologists and medical doctors specializing in microbiology, obstetrics and paediatric allergology. Hypotheses We hypothesise that:

• The immune maturation of the child is prominently affected by the maternal microbial and dietary environment during pregnancy, and by the pioneer microbiome provided by the mother during natural childbirth. These changes are long-lasting and mediated by epigenetic and immune-mediated mechanisms, resulting in a more efficient downregulation of postnatal Th2 responses and normal tolerance development.

• Perinatal probiotic and ?-3 PUFA supplementation can stimulate this tolerance development via induction of regulatory T cells and/or of Th1-like immunity, especially when given already from the period of pregnancy where the immune system of the child is starting to be shaped. Significance

Efficacious preventive measures, required to combat the allergy epidemic, may be identified by determining how the immune interaction between mother and child is influenced by microbial factors and regulated by epigenetic mechanisms. Asthma is the most common chronic disease among children. Providing CS delivered neonates with the maternal pioneer microbiome they would have obtained if delivered vaginally may enhance gut and oral microbiota diversity during infancy and reduce allergy development.