The Human Genome Project provided researchers with valuable information by identifying and mapping the three billion DNA base pairs and estimated 25,000 human genes that make up the human genetic code. Likewise, cell scientists across the globe are collaborating on the construction of a similarly detailed atlas of all human cells.
Part of that effort is the Human BioMolecular Atlas Program (HuBMAP), a National Institutes of Health (NIH) Common Fund Program that began in 2018 with the aim of mapping human tissues at the individual cell level. Together with an international effort to create the Human Cell Atlas, the HuBMAP platform will bring together data to build detailed and comprehensive biomolecular maps of human tissues. According to HuBMAP program leader Richard Conroy, this information could become the “Google map of the human body atlas.”
“Human bodies have more than 40 trillion cells,” Conroy said. “We want to find out not only which types of cells are there, but how they are organized spatially, and how they vary from person to person and within individuals over time.”
The NIH program is specifically geared toward defining the spatial orientation of cell types. The end result, Conroy said, is to create a baseline of what is normal and what is otherwise a disease state. “Our challenge is: How do we approach this as a coordinated effort across all the PIs and funders to make sure that what we are doing is complementary to one another? How do we make sure we are sampling in the right space and over the course of lifespan?”
The NIH has multiple programs to study different parts of the body, Conroy explained, such as The Brain Initiative® Cell Census Network, The Human Tumor Atlas, and other groups working on mapping cells in the lung, the kidney, and other organs. “HuBMAP is trying to knit these different programs together,” he said.
One benefit that Conroy envisions from all these gathered data is better tissue engineering. Synthesizing data about the vascular system, the lymphatic system, and how tissues are innervated, he says, will elucidate the fundamental principles of how tissues are organized.
The atlases will also take into account the cell cycles of the hundreds of different cell types, how they interact with each other in different environments, and more. These atlases will also address what Conroy referred to as the “dark matter” between cells. “We know there is a complex extracellular environment between cells and we want to know more about what happens in these areas and how important they are,” he added.
By combining the sequencing of DNA and RNA with advanced imaging methods, researchers can obtain both the genetic and the spatial data need to complete initial drafts of the human cell atlas. Conroy says that first drafts could be realized within the next three to five years. “In the last five years there has been an explosion of sequencing and imaging techniques that have enabled this kind of work,” he said.
Conroy and his colleague Ananda L. Roy have published a review of the state of the art on the human cell atlas in Molecular Biology of the Cell. The Perspective, “Toward mapping the human body at a cellular resolution,” can be found in the August 1, 2018, issue.