Development of the child's immune system | Bellavie
Development of the child's immune system
By Jocelyne Prunt-Sabourin, naturopath
31 July, 2024 by
Development of the child's immune system
Sales Team

A child's immune system develops much earlier than we thought.

If at the embryonic stage, it is protected by immunoglobulins transmitted by its mother. This is known as passive immunity, which protects the baby for up to 6 months after birth.

The real development of the immune system begins in the second trimester, notably with the formation of the thymus, but also of specific cells, called dendritic cells, which will have a very specific and essential role for its future development.

In fact, a 2017 study published in Nature highlighted the existence of an immune system in the fetus as early as the second trimester of pregnancy. This recognizes foreign proteins via dendritic cells. However, this leads to a very different mechanism from that of the adult, since it involves tolerating the mother's proteins.

And let's not forget that immunity is closely linked to the development of intestinal microbiota, a development that takes place later in life.

Bacterial colonization begins at birth with the mother's vaginal bacteria, then orally with breastfeeding, and via the respiratory and cutaneous tracts with microorganisms present in the environment. In this way, the baby's microbiota is gradually enriched until it reaches maturity at around 2-3 years of age. For children born by caesarean section, maturation will take longer, leading to a less varied intestinal flora.

The gradual introduction of foods will also bring in other microorganisms that will enrich the child's microbiota.

But childhood is a delicate period, and the intestinal flora can easily be disturbed (infections, antibiotics, diet...). Probiotic supplementation can be useful in a variety of cases, whether as a curative measure to reduce the duration and intensity of symptoms, or as a preventive measure to reduce risks. For example

- For acute diarrhea, whether viral or bacterial

- For diarrhea caused by antibiotics

- Respiratory infections 

- Allergies such as dermatitis, eczema, allergic rhinitis and asthma

- For food intolerances...

 A good microbiota is also essential for brain development

Laboratories have therefore developed pediatric formulations to meet the specific needs of children, both in terms of the choice of strains and their quantity.

Don't hesitate to ask your laboratory, pharmacist or doctor for advice.

Ledford, H. , Eye-opening picture of fetal immune system emerges. Nature 546, 335–336 (2017). https://doi.org/10.1038/546335a,

https://www.nature.com/articles/546335a

Shohei Akagawa et al., Development of the gut microbiota and dysbiosis in children, Biosci Microbiota Food Health,  2021;40(1), 12-18.

https://doi.org/10.12938/bmfh.2020-034 

https://pubmed.ncbi.nlm.nih.gov/33520564/

Bohbot J, Bellaiche M, Mosca A. Microbiotes: 1000 jours à ne pas négliger,. La Revue des Microbiotes. 2015;(3), pp. 4-11.

https://www.larevuedesmicrobiotes.fr/les-numeros/microbiotes-1000-jours-a-ne-pas-negliger

L’utilisation des probiotiques dans la population pédiatrique, résumé d’un article paru dans Paediatr. Child Health en 2022

https://cps.ca/fr/documents/position/probiotiques-dans-la-population-pediatrique

https://www.researchgate.net/publication/315385914_L'utilisation_des_probiotiques_au_sein_de_la_population_pediatrique


Kelsey Fehr et al., Breastmilk Feeding Practices Are Associated with the Co-Occurrence of Bacteria in Mothers’ Milk and the Infant Gut: the CHILD Cohort Study, Cell Host & Microbe, volume 28, Issue 2, 12 August 2020, pp. 285-297.e4

https://www.sciencedirect.com/science/article/pii/S1931312820303504?via%3Dihub

Childhood Brain Growth Linked to Gut Microbiome, article web 2023 sur

https://neurosciencenews.com/microbiome-brain-development-25393/#:~:text=The%20research%20reveals%20a%20connection%20between%20the%20gut,more%20prevalent%20in%20children%20with%20lower%20cognitive%20scores

Hannah E. Laue et al., The developing microbiome from birth to 3 years : the gut brain axis and neurodevelopmental outcomes, Frontiers in pediatrics, march 2022, volume 10

file:///C:/Users/Proprietaire/Documents/fped-10-815885.pdf