Results from three long-term studies following host and microbiome characteristics during pregnancy and preterm birth, inflammatory bowel disease, and prediabetes have expanded our understanding of how humans and microbes interact and the resulting consequences for our health. The studies were funded as part of a second phase of the National Institutes of Health’s Human Microbiome Project (HMP). Key findings, datasets and new techniques developed over the course of this phase were published in a series of research articles in the Nature family of journals.
The NIH Common Fund launched the HMP in 2007 to develop resources for characterizing the microbiome in healthy adults and in people with specific microbiome-associated diseases. The second phase of the HMP, the integrative HMP or iHMP, emphasized human and microbiome interactions and analyzed the temporal trends in many biological properties of them both. Three known microbiome-associated conditions served as models for the iHMP to develop new approaches and tools for microbiome research.
“The first phase of the HMP revolutionized our understanding of the healthy human microbiome and gave us clues to its role in a few human diseases,” said James M. Anderson, M.D., Ph.D., director of the Division of Program Coordination, Planning, and Strategic Initiatives, which oversees the Common Fund. “Research now shows that just identifying the microbes that make up a person’s microbiome is not enough to understand the microbes’ health consequences. The function of a microbial community is different from the sum of the individual microbes’ behavior.”
An iHMP project at Virginia Commonwealth University, Richmond, focused on the vaginal microbiome and the host immune system in women who give birth preterm versus those who give birth at term. The team of researchers followed more than 1,500 women over the course of pregnancy, and identified specific microbes present early in pregnancy in women who experienced preterm birth. The researchers also discovered a profile of inflammatory molecular signals in the women who experienced preterm birth together with a distinct metabolic profile in their microbiomes. These profiles were observed very early in pregnancy, which may provide new clinical biomarkers to predict women at risk of preterm birth.