The Immune System of Milk

We know that breastfeeding is good for children’s health in many ways. Immune factors in milk—including antibodies and other proteins, white blood cells, and even commensal microbes—protect infants against infections and may prevent allergies. Understanding how the “immune system of milk” responds to microbes is critically important to understanding how breastfeeding affects children’s health.

The Laboratory for Anthropometry and Biomarkers at Binghamton University (Director, Katherine Wander) is developing a new technique to test how the “immune system of milk” responds to microbes. Our technique “challenges” the immune system of milk with an infectious agent and measures its response. The protocol is simple and low-tech. Milk is diluted in culture medium (which keeps milk cells alive and allows them to respond), an immune stimulant (all or part of an infectious agent, like E. coli) is introduced, and milk is incubated at ~98.6° F for 24 hours. We then measure the concentration of cytokines—mediators of immune responses produced by immune cells—in stimulated and unstimulated milk. We describe milk immune responses to stimuli by comparing cytokine concentrations before and after incubation.

Initial findings: The first phase of The Immune System of Milk was a success—we were able to develop a method to describe immune responses in milk. ~40 women provided milk specimens. We used half of these to develop the protocol and half to characterize milk immune responses with the final protocol.

We challenged the immune system of milk with two stimuli: the surface antigen of E. coli and a vaccine strain of Mycobacterium. We measured a few cytokines, and found dramatic increases—up to 65 times baseline—in the cytokine interleukin-6 in some milk specimens. This is a good indication that milk immune cells in those specimens were responding to the stimuli. Immune responses were apparent in about half of milk specimens.

Future directions: Now that we have “proof of concept” that immune responses in milk can be detected with our technique, we will work to refine it, by including more stimuli and evaluating more cytokines. We are particularly interested in evaluating immune responses to infectious agents that commonly cause gastrointestinal diseases and most commonly affect young children, like rotavirus.

We will use this protocol in larger studies to describe how milk immune responses connect mothers’ and infants’ health. For example, future projects can ask questions like:

  • Are milk immune responses compromised when mothers are malnourished?
  • Do milk immune responses affect infants’ infectious disease risk?
  • Do milk immune responses affect infants’ allergic disease risk?

The LAB  and the Child Health and Development in Kilimanjaro project focus on conducting international health research in remote settings where understanding early childhood nutrition and infectious disease are critical.

We are not currently enrolling participants in The Immune System of Milk. We will continue to update this page with new information about the project. If you have any questions about the study, please contact Katherine Wander by email at

Last Updated: 1/4/17