Most people would probably prefer if traces of dairy cows' vaccinations don't show up in their milk, but one research team is looking into deliberately adding antibodies to milk as a way to help malnourished children in developing countries.
Seven years ago Alan Cross, a professor at the University of Maryland School of Medicine, published the results of a successful phase I clinical trial of a vaccine against sepsis he had developed. His next step, however, is to vaccinate dairy cows, not people. The cows will then produce an antibody-rich colostrum—the first milk mammals make after giving birth that transfers immunity to newborn animals—which organizations can give to malnourished children as a nutritional supplement.
Malnutrition causes the interior walls of the intestines to break down, allowing bacteria to move from the gut into the bloodstream, which leads to sepsis and a weakened immune system. For a child who has been malnourished for awhile, starting back on food is often insufficient to prevent illness and diarrhea, says Zeil Rosenberg, CEO of Bali Biosciences, LLC. The company has a license agreement with the University of Maryland, Baltimore, to produce the sepsis antibody colostrum. Rosenberg hopes that the milk, used along with food aid, will help break the "viscous cycle of malnutrition." In the past Rosenberg worked with Indonesia's Ministry of Health in Jakarta as a U.S. Agency for International Development advisor.
Once a child takes the colostrum, sepsis antibodies should enter his or her digestive system where they can bind to the toxins produced by sepsis-causing gram-negative bacteria such as Escherichia coli, Rosenberg says. The antibody-neutralized toxins might then leave the body via the feces, although researchers are not yet sure exactly how the colostrum will promote such evacuation.
Cross and Rosenberg also hope the antibody-rich milk will help trauma and burn patients, who are especially vulnerable to sepsis, but the first target audience for their product are malnourished children.
"It's an absolutely fascinating idea and completely original," says William Schaffner, a physician who researches infectious diseases at Vanderbilt University School of Medicine. Charles Arntzen, an Arizona State University School of Life Sciences biologist who studies vaccine development, says the idea sounds feasible as a way to block the onset of blood infection from the gut.
The colostrum should cost far less than conventional vaccine shots or intravenous treatment, making it less of a financial burden for developing nations. Rosenberg couldn't guess how much the final product might cost, but Arntzen notes that dairy cows make great quantities of colostrum, and immunizing cows is a common and inexpensive procedure.
Experts also expect the treatment to be very safe. Bali Biosciences will remove some of the lactose in the colostrum to make it more digestible for people who are lactose-intolerant, says Rosenberg. "As far as I can tell, they're not going to have any safety issues," Schaffner says. "This is like drinking [regular] cow's milk." The expected safety of the colostrum will help keep its test costs down.
Bali Biosciences continues to seek an organization to help distribute their product if it works, Cross says. Meanwhile, he'll be immunizing pregnant cows and testing their colostrum for the antibodies he's interested in. If the antibodies show up, he'll test the milk in animal models. He received a yearlong Maryland Proof of Concept Alliance grant last week to run his experiments.
In spite of billions of dollars spent in food aid, more than three million children die of malnutrition every year, according to the World Health Organization. Part of that mortality comes from infections that cross from the children's digestive systems into their blood, Rosenberg says. "We don't think there's one solution," he says, "but we think we can be part of a package of solutions."