CD14 A cell surface protein abundant in human milk, is present when the immune system learns to fight pathogens in the intestines. Nestlé researchers think the protein could turn out to help adult patients suffering from the immune responses that cause Crohn’s disease.
Lactoferrin A human-milk protein that binds iron, helps the body fight Shigella, Salmonella, E. coli, and other microbes that feed on iron. A supplement called Lactoferrin Gold 1.8, marketed by Nikken in Japan, is made from the milk of transgenic cows manipulated to have a human lactoferrin gene. The current process for producing lactoferrin is so inefficient that it requires nearly a gallon of cow’s milk to create just one capsule of the stuff. Yet the treatment may be worth it for the most vulnerable. Already shown to work in pigs, whose immune systems are much like ours, lactoferrin could provide a boost for those with compromised immune systems such as infants, the elderly, and the chronically ill.
Lysozyme An enzyme found in low levels in human milk, has been shown to kill E. coli in mice and pigs; it could soon find medical applications. To boost production of the enzyme in animals, U.C. Davis scientists have transferred the human gene for the enzyme into dairy goats. Although regulations prevent the transgenic milk product from being sold, the researchers are working with the Brazilian government to test it in the northeastern part of the country, where childhood diarrhea is common and some areas have infant mortality rates up to 10 percent.
See the related feature, "The Impressive Power of Breast Milk."