Finally, A Map Of All The Microbes On Your Body

Enlarge Ayodhya Ouditt/NPR

Ayodhya Ouditt/NPR

Scientists Wednesday unveiled the first catalog of the bacteria, viruses and other microorganisms that populate every nook and cranny of the human body.

Researchers hope the advance marks an important step towards understanding how microbes help make humans human.

The human body contains about 100 trillion cells, but only maybe one in 10 of those cells is actually � human. The rest are from bacteria, viruses and other microorganisms.

"The human we see in the mirror is made up of more microbes than human," said Lita Proctor of the National Institutes of Health, who's leading the Human Microbiome Project.

 

"The definition of a human microbiome is all the microbial microbes that live in and on our bodies but also all the genes � all the metabolic capabilities they bring to supporting human health," she said.

These microbes aren't just along for the ride. They're there for a reason. We have a symbiotic relationship with them � we give them a place to live, and they help keep us alive.

"They belong in and on our bodies; they help support our health; they help digest our food and provide many kinds of protective mechanisms for human health," Protor said.

Microbes extract vitamins and other nutrients we need to survive, teach our immune systems how to recognize dangerous invaders and even produce helpful anti-inflammatory compounds and chemicals that fight off other bugs that could make us sick.

"These microbes are part of our evolution. As far as we can tell, they are very important in human health and probably very important in human disease as well," said Martin Blaser of New York University.

These bugs generally don't make us sick. But when we disrupt the delicate ecosystems they carefully construct in different parts of our bodies, scientists think that can make us sick.

"There can be a disturbance in the immune system. There can become some kind of imbalance. And then you can get a microorganism which, under normal circumstances, lives in a benign way and can become a disease-bearing organism," Proctor said.

Taking too many antibiotics, our obsession with cleanliness and even maybe the increase in babies being delivered by Caesarean section may disrupt the normal microbiome, she said.

So the idea behind the micobiome project was to get the first map of what a normal, healthy microbiome looks like.

More than 200 scientists spent five years analyzing samples from more than 200 healthy adults. The samples came from 18 different places on their bodies, including their mouths, noses, guts, behind each ear and inside each elbow.

"This is the only study to date anywhere in the world where peoples' microbiomes across a human body were sampled and analyzed. Here was an effort to really investigate the full landscape, if you will, of the human microbiome across the body," Proctor said.

Scientists identified some 10,000 species of microbes, including many never seen before, according to the first wave of results, which are being published in 16 papers in the journals Nature and PLoS.

"This is like going into uncharted territory � going into a forest and finding a new species of butterfly or new type of mammal or something like that � a new kind of bird," said George Weinstock of Washington University in St. Louis.

Those 10,000 or so species have more than 8 million genes, which is more than 300 times the number of human genes.

And scientists found some very interesting things when comparing microbiomes.

"People were very different from each other, but skin was more like skin and gut was more like gut. So the composition of microbes and the kinds of genes that they have are very much habitat-specific," Proctor said.

Now that scientists have an idea of what a healthy microbiome looks like, they can start to explore this super-organism � this complex mishmash of human and microbial cells.

"How do they talk to our human cells? And how do human cells talk back to them? Because it's really a concert that they're playing together, and that's what makes us who we are," Weinstock said.

Scientists have already discovered some intriguing clues. For example, the microbes in a pregnant woman's birth canal start to change just before she gives birth. Scientists think that's so their babies are born with just the right microbiome they'll need to live long, healthy lives.

HHS to dig deeper for better decisions

WASHINGTON – For San Francisco-based Archimedes, a company named for a Greek mathematician of antiquity, it’s all about data, math, computing and healthcare modeling. The 20-year-old company deals in information – of the quantitative type. And now it will bring its high-powered analytics skills to bear for the Department of Health and Human Services.

Under a contract with HHS announced last month, Archimedes will dig into large quantities of data to provide several HHS agencies the ability to evaluate the effectiveness of specific health interventions more quickly and more accurately. HHS officials say it signals "a new era of medical decision-making."

The technology will enable the agencies to research, analyze and evaluate the effects of specific healthcare interventions more quickly and accurately, Archimedes executives say.

The company bills the Archimedes Model, developed initially with support from Kaiser Permanente, as “the most advanced mathematical modeling tool available to answer complex questions on health and healthcare.”

Under the contract, HHS will make a new Web-based interface called the Archimedes Healthcare Simulator (ARCHeS) available to its agencies, including the Centers for Medicare & Medicaid Services (CMS), the Centers for Disease Control and Prevention (CDC), the Agency for Healthcare Research and Quality (AHRQ), the National Heart, Lung & Blood Institute and the Food & Drug Administration (FDA).

A $15.6 million grant from the Robert Wood Johnson Foundation (RWJF) Pioneer Portfolio in 2007 supported the creation of ARCHeS, which makes the Archimedes Model more accessible and affordable for public policymakers and nonprofit users.

“When we initially made this grant, I said that the development of ARCHeS would usher in a new era in medical decision-making that we believe has the potential to transform health and healthcare,” said Risa Lavizzo-Mourey, MD, president and CEO of the Robert Wood Johnson Foundation. “By getting ARCHeS in the hands of HHS and all of its agencies, we’ve taken a very big step toward realizing that potential. Our goal has always been to create access to this innovation for the public policymakers and researchers best positioned to use it to inform decisions that will improve health and healthcare for all Americans. We now see that happening.”

“The quality and cost of healthcare are determined by decisions made by policymakers, physicians and others. To make those decisions wisely, decision makers need to know the consequences of the different options they face,” said David Eddy, MD, founder and chief medical officer of Archimedes. “For a high proportion of decisions, the only feasible way to get the needed information is to use mathematical models that integrate existing evidence, and are validated against evidence.

In his view, the contract with HHS will put the analytical power of advanced healthcare modeling on the desks of decision makers in the federal government.

“By combining this tool with their own insights and experience, decision makers will be able to understand much better the effects of different policies, and be able to design policies that achieve the twin goals of improving quality and controlling costs,” said Eddy.

In one of a number of analyses already performed by Archimedes, Kaiser Permanente used forecasts from the model as the impetus to launch a program to provide a bundle of aspirin, lovastatin (a cholesterol-lowering drug), and lisinopril (a blood pressure-reducing drug), to high-risk members. This analysis was used in informing the implementation of Kaiser Permanente’s ALL/PHASE program. The result was a more than 60 percent reduction in heart attacks and strokes over a two-year period.

As a result of HITECH Act and the Patient Protection and Affordable Care Act, the use of modeling and simulation platforms is in high demand for policymakers and researchers. Both of these laws include new requirements for use of data in the design of health benefits; comparative effectiveness of quality, cost, and outcomes; and evaluation of population health efforts.

In March, the federal government launched a research initiative in big data computing for a number of agencies, including the National Institutes of Health.

"The federal government sees a growing need across all of its agencies for innovative resources to aid in research, policy analysis and evaluation,” said U.S. Chief Technology Officer Todd Park. "We’re excited that ARCHeS will now be available to staff across the Department of Health and Human Services. It gives us an important new tool to analyze a wide variety of health policy questions and quickly compare different scenarios and outcomes.”