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) has developed 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. ~100 women provided milk specimens. We used these to develop a protocol that allows us to characterize milk immune responses to many gastrointestinal pathogens, including Salmonella, rotavirus, and parasitic worms, and to commensal bacteria, like Lactobacillus.
Cytokines increased dramatically—up to 600 times baseline—in some milk specimens when challenged with gastrointestinal pathogens. Immune responses were apparent in about half of milk specimens. Immune responses were generally much greater for Salmonella than for commensal bacteria.
Immune responses were not correlated with mother or child age. Milk immune responses were greater, on average, for mothers with diagnosed autoimmune disease.
Future directions: Now that we have perfected this protocol, we will use it to investigate the importance of milk immunity among children in Kilimanjaro, Tanzania, where gastrointestinal infections are very common and milk immunity is likely to be critical to children's health.
We will investigate whether strong milk immune responses can protect infants against infectious diseases, and whether milk immune responses become stronger when infants become ill. Data collection on this project will begin in Kilimanjaro in 2019.
More information about the Child Health and Development in Kilimanjaro project can be found here. The LAB and CHDK focus on conducting international health research in remote settings where understanding early childhood nutrition and infectious disease are critical.
In the future, our technique can also be used in research asking questions like:
- Are milk immune responses compromised when mothers are malnourished?
- Do milk immune responses affect infants' autoimmune or allergic disease risk?
This project would not have been possible without our participants, who volunteered their time and donated milk to this project. We are eternally grateful for your patience and your support. We are also grateful to La Leche League of Greater Binghamton and the Southern Tier Breastfeeding Coalition for help in this project.
If you are looking for more about the projects findings, please visit the LAB's main page and view the Publications/Posters section.
Students, if you would like to apply to work on this project, please contact Katherine Wander (firstname.lastname@example.org).