Breast milk provides baby molecule to build immunity

Washington, Oct 27 : A molecule holds the key to mothers' ability to strengthen the immunity of the baby through breast milk, according to a latest research.

The study highlights the amazing change that takes place in a mother's body when she begins producing breast milk.

Years before her pregnancy, cells that produce antibodies against intestinal infections travel around her circulatory system and regularly take an "off-ramp" to her intestine.

There they stand guard against infections like cholera or rotavirus. But once she begins lactating, some of these antibody-producing cells suddenly begin taking a different off-ramp that leads to the mammary glands.

That way, when her baby nurses, the antibodies go straight to their intestine and offer protection while the baby builds up its own immunity. This is why previous studies have shown that formula-fed infants have twice the incidence of diarroheal illness as breast-fed infants.

Until now, scientists did not know how the mother's body signalled the antibody-producing cells to take the different off-ramp. The new study identifies the molecule that gives them the green light.

"Everybody hears that breast feeding is good for the baby," said Eric Wilson, Brigham Young University microbiologist who is a co-author of the study.

"But why is it good? One of the reasons is that mothers' milk carries protective antibodies which shield the newborn from infection, and this study demonstrates the molecular mechanisms used by the mother's body to get these antibody-producing cells where they need to be."

Understanding the role of the molecule, called CCR10, also has implications for potential future efforts to help mothers better protect their infants, according to a release from the Brigham University.

Wilson's other co-authors are Yuetching Law, Kathryn Distelhorst and Erica D. Hill.

Harvard Medical School co-authors are Olivier Morteau, Craig Gerard, Bao Lu, Sorina Ghiran and Miriam Rits. Stanford University School of Medicine co-authors are Raymond Kwan, Nicole H. Lazarus and Eugene C. Butcher.

These findings are scheduled for publication in Nov 1 issue of the Journal of Immunology.

--IANS