Discovery of a crucial immune reaction when solid food is introduced that prevents inflammatory disorders
Reduced exposure to microbes at an early age could lead to increased susceptibility to allergic or autoimmune diseases.
Microbes colonize all body surfaces and help to balance the immune system. In newborn infants, gut microbiota is first conditioned by breast milk components. When solid food is introduced, gut microbiota develops and bacteria proliferate.
Scientists from the Institut Pasteur and Inserm have discovered that a key immune response is generated in mice when solid food is introduced and microbiota expands. But, above all, they have shown that this immune reaction is essential as it is involved in educating the immune system and leads to low susceptibility to inflammatory disorders (allergies, colitis, autoimmune diseases, cancer) in adulthood. These findings were published in the journal Immunity on March 19, 2019.
In newborn infants, the composition of the gut microbiota is determined at birth by the bacteria acquired from the mother and the composition of breast milk. It mainly features bifidobacteria and lactobacilli. When new foods are introduced, the microbiota proliferates and the number of bacteria increases 10- to 100-fold.
Scientists (Ziad Al Nabhani and his colleagues) from the Microenvironment and Immunity Unit (Institut Pasteur/Inserm), led by Gérard Eberl, have discovered that this phenomenon triggers an intense immune response in mice. “We showed that this mechanism takes place within a very specific time window: between two and four weeks in mice which corresponds to three to six months in humans” explains Gérard Eberl, the lead author of the study.
All this data highlights the importance of early life exposure to microbiota for the development of a balanced immune system. “We would now like to confirm these findings on the impact of microbiota at weaning in the context of other pathologies, such as neurodegenerative diseases for example” concludes Gérard Eberl.
Read full article at https://www.sciencedaily.com/releases/2019/03/190319125901.htm