Dr. Meghan Koch, an immunologist at Fred Hutchinson Cancer Research Center, has been named a 2019 Rita Allen Foundation Scholar. She studies how interactions between mother and infant influence infant growth and development. The Koch Lab particularly seeks to understand how immune factors passed from mother to baby shape its developing microbial communities and immune system, and how these effects influence growth.
The mission of the Rita Allen Foundation, established in 1953, is to support transformative, human health–promoting ideas in their earliest stages. The Scholars, all early-career biomedical scientists, are selected based on their creative, promising approaches to investigating crucial problems that raise the potential for significant breakthroughs in their fields of study. They receive up to $110,000 per year for up to five years to facilitate their work.
“Broadly my interests are in understanding how maternal-offspring interactions influence health,” said Koch, who joined the Basic Sciences Division faculty in 2018.
During her postdoctoral training, Koch became interested in how immune responses to the microbiome, the microbes that live in our gut, our mouths, our eyes, our skin and other body parts, are established. Immediately after birth, infants are colonized by a sudden flood of microbes. Their immune systems must learn to discriminate friendly bacteria from deadly pathogenic bacteria, and when to mount — or avoid mounting — an inflammatory response. But many of the strategies that adult immune systems use to make peace with nonpathogenic bacteria are missing from the infant immune system, Koch said. Perhaps, she thought, factors from the mother could be making up the difference.
“The mother is also the source, primarily, of these microbes that are colonizing her young. The idea is not only is she providing these microbes, she’s also providing some kind of instruction for how to appropriately respond or deal with this incoming tsunami of microbes,” Koch said.
That instruction, she suspected, could be coming in part from specialized proteins called antibodies. Mothers pass antibodies to their offspring in utero and through breast milk. It’s well known that these antibodies provide some protection against infection as the infant immune system develops. Koch discovered that they do much more.
Using mouse models, she found that the growth of infants whose mothers could not provide antibodies faltered about two weeks after birth, though the young mice caught up again developmentally at six to eight weeks of age. Koch also saw that the spectrum of bacterial species in the guts of infant mice without maternal antibodies was different than that of young mice that received maternal antibodies. And, the mice without maternal antibodies had increased immune activation.
“These mice are receiving adequate nutrition, they are not infected with any pathogens, and yet they’re still exhibiting this impaired weight gain during this specific period of life,” Koch said. “It’s indicating that somehow these antibodies are functioning to promote growth.”
The Rita Allen Foundation funds will help her parse out how. Koch plans to tease apart what is causing growth faltering in these mice — whether it’s microbial changes, immune response changes, or both — and how, such as through impaired nutrient absorption or increased energy expenditure. This understanding could be the first step toward designing ways to counterbalance these changes in infants not exposed to maternal antibodies.
Though her studies are currently confined to mice, Koch is working to extend them to humans. Growth faltering or failure to thrive in young children is a public health issue in low-resource areas. While inadequate nutrition is a major contributing factor to growth faltering, merely restoring nutrition doesn’t always solve the problem, suggesting that non-nutritional factors are involved, Koch said.
Infection, for example, could be one factor that could influence how well children digest food or change the composition of their microbiome and ability to extract nutrients from food.
“If we can understand how these beneficial relationships are formed between the host and the microbiota, then we can better treat impaired growth during early life,” perhaps by adding new ingredients to breast milk that mimic its non-nutritive, growth-enhancing components, Koch said.
Previous Rita Allen Foundation Scholars from the Hutch include the late Dr. Hal Weintraub, who helped found the Hutch’s Basic Sciences Division, Dr. Bruce Edgar (now with the Huntsman Cancer Institute at the University of Utah) and Dr. Adrian Ferré-D’Amaré (now with the Intramural Research Program at the National Institutes of Health). Dr. Emily Hatch, a basic scientist, was named a Rita Allen Foundation Scholar in 2018.
Many former Rita Allen Foundation Scholars have made breakthrough discoveries in their fields, some of which have been recognized with awards including the Nobel Prize in physiology or medicine, the National Medal of Science, the Wolf Prize in Medicine, the Lasker-Koshland Special Achievement Award in Medical Science and the Breakthrough Prize in Life Sciences.
Sabrina Richards, a staff writer at Fred Hutchinson Cancer Center, has written about scientific research and the environment for The Scientist and OnEarth Magazine. She has a PhD in immunology from the University of Washington, an MA in journalism and an advanced certificate from the Science, Health and Environmental Reporting Program at New York University. Reach her at firstname.lastname@example.org.