Infant formula manufacturer Nestle partially funded new research revealing how a protein in breastmilk protects babies from respiratory infections. The QIMR Berghofer Medical Research Institute study, published today in the science journal Cell, identified osteopontin as a key component. This protein triggers a cascade of biological processes that kickstart immune system development in early life.
Immunologist Simon Phipps, who led the international research group, stated that while breastfeeding's protective effects were known, the underlying cause remained unclear. Scientists have long understood that osteopontin is present in high levels in mother's breastmilk during the early weeks after birth. Its influence on infant health, however, had been a mystery until now.
Professor Phipps and his colleagues compared the immune systems of baby mice. Some were fed osteopontin concentrated from cow's milk, others were not, after exposure to a respiratory tract infection. He reported that mice not receiving osteopontin had lower numbers of crucial immune cells. These cells help defend the baby against infection. Supplementing the osteopontin protected those baby mice from the infection.
Dozens of scientists collaborated, finding osteopontin altered the baby mice's gut microbiomes. The microbiome, a collection of micro-organisms, develops in the digestive tract in early life. Professor Phipps explained that osteopontin changed the production of bacterial metabolites in the gut. These chemicals then acted on cells, including those lining the lungs, to activate growth factors that boosted immune system development. The five-year study also found a drug used for type 2 diabetes could mimic osteopontin's effects by activating the same immune processes.
Who Profits from Natural Science?
Professor Phipps's laboratory is now in discussions with infant formula companies. The goal is to use this research to understand how breastmilk components promote immunity. This knowledge could then be taken on board by companies to “potentially improve the quality of the infant formula.” The research, which uncovers the benefits of a natural, free resource, was partially funded by Nestle, a corporation whose primary business is the sale of manufactured infant formula. Australia's National Health and Medical Research Council (NHMRC) also contributed partial funding. This represents a clear instance of public and corporate capital converging to potentially commodify natural biological processes.
The Burden on Working Mothers
The study's findings underscore the inherent value of natural milk, yet the system continues to place the burden of access and provision on individual mothers. Physiotherapist Bethany Kippen, who gave birth to her first baby Billy late last month, described her initial breastfeeding journey as “really tough.” She found it became a “most rewarding experience” once she and her baby established a rhythm. Her experience highlights the personal effort required in a society that often fails to provide adequate structural support for breastfeeding.
Griffith University Associate Professor Valerie Slavin, a maternity care and public health researcher, emphasized that while findings on breastfeeding are “exciting,” the greatest gains for mothers and babies would come from improving access to breastfeeding support. She noted that many women stop breastfeeding earlier than planned due to a lack of “timely, practical or consistent support.” Slavin advocated for “investing in systems that help women achieve their breastfeeding goals,” a reformist approach that does not challenge the underlying economic pressures on working mothers.
Professor Ben Desbrow, a nutrition and dietetics expert not involved in the study, acknowledged its “exceptional science.” He suggested that milk banks, where breastfeeding women donate excess milk, may become increasingly important. This collective solution points to the need for community-based support in the face of systemic challenges. Desbrow stated that the effects observed are “likely to have lifelong benefits to the individual,” reducing infections in neonates and potentially impacting lung conditions later in life. This reinforces the profound, uncommodified value of breastmilk. Research fellow Lisa Stinson of the University of Western Australia Centre for Human Lactation Research and Translation called the study “strong foundational science,” but cautioned that more human studies are needed before definitive statements can be made about osteopontin's effects in babies.