Breastfeeding is known to develop the immune system in infants and also influences numerous immunological responses later in life. Breast milk is a rich source of early nutrition that aids in infant growth and development. However, certain compounds in breast milk invaded as a result of an unhealthy lifestyle or the diet of lactating mothers may have a negative impact on the infants. 

A study found the presence of damage-associated molecular patterns (DAMPs) activity in the mother’s milk. The researchers utilized the non-targeted metabolomic analysis to identify the long-chain saturated fatty acids (LCSFA) as a biomarker DAMPs (+) in the breast milk samples. 

They also proved LCSFA to be a type of damage-associated molecular patterns which initiate a series of inflammatory events in the gut involving type 3 innate lymphoid cells (ILC3s). 

The highlights of the study are follows-

• The study demonstrated a remarkable increase in inflammatory ILC3s in the gut and the migration of these ILC3s to the skin which may act as a potential trigger of Atopic dermatitis (AD).
• An upregulation of genes that increase ILC3s and chemokines/chemokine receptors, which is thought to have a role in ILC migration to the skin was observed in the Gene expression analysis of ILC3s isolated from the gut.
• Gut microbiota of AD-prone PA milk-fed mice was found to be different from non-AD oleic acid (OA)/normal diet (ND) milk-fed mice. 

Thus it was concluded that the early exposure to LCSFAs in infants disturbs the balance of intestinal innate immunity by creating a highly inflammatory environment with the proliferation of ILC3s and production of interleukin-17 and interleukin-22. These factors may act as potential triggers or worsening factors of AD.

Source: Sci Rep. 2021;11(1):13109. Published 2021 Jun 23. doi:10.1038/s41598-021-92282-0