For your next vacation, try ditching your GPS and smartphone.
Instead, drive across the country using one of those maps you colored in elementary school. It probably has all the states on it and maybe a few rivers and lakes.
Of course, it might be easier to get where you’re going if you had a few more details — like the streets and roads, and even the tolls.
Now imagine what it would be like to find your way around the human body with only a grade school sketch of its trillions of cells.
That’s the problem faced by scientists trying to understand and find new treatments for diseases like cancer, Alzheimer’s, and asthma.
But an ambitious new project announced earlier this month in London to build a complete map of the human body hopes to give researchers a little navigational assistance.
“The cell is the key to understanding the biology of health and disease, but we are currently limited in our understanding of how cells differ across each organ, or even how many cell types there are in the body,” Sarah Teichmann, Ph.D., head of cellular genetics at the Sanger Institute, said in a press release for the meeting.
Detailed map of the human body
Many science resources list about 200 different types of cells in the human body — such as skin, heart, and muscle cells.
By lumping the trillions of cells in the body into large groups, though, you lose many of the details.
Much medical research is done the same way, with researchers looking at the average cellular activity in a tissue rather than the variation that occurs throughout the tissue.
The Human Cell Atlas would zoom in the map — down to the individual cell level.
It will include an inventory of the cell types and subtypes in the body, their locations, how they change over time during health and disease, and which genes are turned on in each cell.
This reference map would be an open resource that scientists can use to support their own research.
Some researchers have compared the initiative to the Human Genome Project (HGP) — which catalogued the full human genetic sequence — although the new project faces many unique challenges.
“The types of data to be collected within each of the individual cell populations — and individual cells — will be much more diverse, and there will be huge challenges in data integration that may not have been as complex in the HGP,” Justin Balko, Pharm.D., Ph.D., an assistant professor of medicine and cancer biology at Vanderbilt University Medical Center, told Healthline in an email.
Researchers from the Wellcome Trust Sanger Institute, the Broad Institute of MIT and Harvard, and other institutions began initial discussions in London in mid-October of what this map would look like.
The group already has a commitment of funding from the Chan Zuckerberg Initiative, which recently announced that it aims to “cure, prevent or manage all disease by the end of this century.”
Analyzing single cells
The Human Cell Atlas will be aided by new technology designed for analyzing single cells.
In 2012, Aviv Regev, Ph.D., from the Broad Institute, and her colleagues used this technology to look at a small group of immune cells called dendritic cells. Of those seemingly 18 identical cells, three turned on different genes than the others.
“We were immediately astounded,” Regev told The Atlantic “It was as if we thought that everyone in a city wore green shirts, and it turned out that some wore blue and some wore yellow.”
She found even larger variation when she examined more than 1,700 dendritic cells.
The cost of these technologies has dropped dramatically in recent years, which should speed up the project.
According to The Atlantic, in 2012 Regev spent thousands of dollars to analyze just those 18 dendritic cells. A year later the price was down to 10 dollars per cell.
Other methods now allow researchers to analyze hundreds of thousands of cells at the same time — at only 6 cents per cell.
This more detailed approach to understanding tissues has many potential applications, such as in cancer research.
“Having a comprehensive picture or catalogue of all cell types in normal tissue will ultimately help us figure out what cells are transforming into cancer, and based on their biology, this will surely lead to hints at better therapies,” said Balko.
Researchers who use stem cells to regenerate damaged or lost tissues might also benefit — how do you know what to build if you don’t know what types of cells are in a tissue?
Even the use of CRISPR to edit DNA could be aided by a better understanding of how cells work and interact by guiding researchers toward the right genes to edit.
Not every researcher contacted by Healthline was even aware of the Human Cell Atlas initiative, so it may take some time for the full impact of this project to be realized.
Still, some researchers are optimistic about the potential.
“It will be very exciting to see how the project plays out,” said Balko. “As more details become available, many of us will begin thinking on early directions to use these exciting data to advance our understanding of cancer biology and the development of new cancer therapies.”