Clues showing how breastmilk helps protect babies found by researchers

Researchers from QIMR Berghofer Medical Research Institute have discovered how a protein found in breastmilk helps protect babies against potentially deadly respiratory infections. Immunologist Simon Phipps led the five-year study, which found that a protein called osteopontin plays a crucial role in immune system development during early life.

Osteopontin triggers a cascade of biological processes that kickstart the development of important immune cells. The researchers compared immune systems of baby mice fed osteopontin with those that were not, finding that those without the protein had lower numbers of crucial immune cells capable of defending against respiratory infections.

Supplementing these mice with osteopontin protected them from the infection. The study suggests that osteopontin alters the baby's gut microbiome by changing the production of bacterial metabolites, which then act on cells lining the lungs to boost immune system development. The researchers also found that a drug used to treat type 2 diabetes could mimic the effects of osteopontin, activating the same immune processes in mice.

This discovery could potentially improve the quality of infant formula by incorporating osteopontin or similar components. While the study was conducted in mice, researchers believe it provides fundamental insights into how nutrition influences early-life immune system development.