Human breast milk provides essential nutrients and antibodies to newborns. Researchers have now found that it also serves as a reservoir for bio-molecules that help clear infections, reduce inflammation, combat pain and heal wounds.
Co-corresponding author Charles Serhan from Brigham and Women's Hospital (BWH) in Boston, US, said, "Finding a reservoir of these inflammation-resolving molecules at bioactive levels was a big surprise for us."
Using a comprehensive profiling technique, the research team was able to uncover a milieu of molecules known as specialized pro-resolving mediators (SPMs) in human breast milk and found that each of these molecules helped resolve inflammation and stimulate immune response in preclinical models. The researchers uncovered a profiling signature consisting of 20 molecules with pro-resolving properties.
The researchers said, "Certain SPMs have been detected in breast milk before, but this is the first time that such a wide variety of bioactive molecules have been uncovered."
Researchers also tested human milk samples from participants with mastitis, an infection of the breast tissue that causes pain and inflammation. They found that SPM levels were much lower in milk from women with mastitis and did not resolve inflammation and infection to the degree that breast milk from non-mastitis samples did.
The research team also tested cow's milk and infant formula where they could not detect SPM levels. Serhan said, "Our results suggest a role for SPM in modulating inflammation, infection and stimulating resolution during early immune development, and further reinforce the importance of human breast milk for infants."
The study was published in the Mucosal Immunology.