The human gut is a remarkable thing. Every week the intestines regenerate a new lining, sloughing off the equivalent surface area of a studio apartment and refurbishing it with new cells. For decades, researchers have known that the party responsible for this extreme makeover were intestinal stem cells, but it wasn’t until this year that Scott Magness, Ph.D., associate professor of medicine, cell biology and physiology, and biomedical engineering, figured out a way to isolate and grow thousands of these elusive cells in the laboratory at one time. This high throughput technological advance now promises to give scientists the ability to study stem cell biology and explore the origins of inflammatory bowel disease, intestinal cancers, and other gastrointestinal disorders.
When Magness and his team first began working with intestinal stem cells some years ago, they quickly found themselves behind the eight ball. Their first technique involved using a specific molecule or marker on the surface of stem cells to make sure they could distinguish stem cells from other intestinal cells.
Then Magness’s team would fish out only the stem cells from intestinal tissues and grow the cells in Petri dishes. But there was a problem. Even though all of the isolated cells had the same stem cell marker, only one out of every 100 could “self-renew” and differentiate into specialized cells like a typical stem cell should. (Stem cells spawn cells that have specialized functions necessary for any organ to work properly.)
“The question was: why didn’t the 99 others behave like stem cells?” Magness said. “We thought it was probably because they’re not all the same, just like everybody named Judy doesn’t look the same. There are all kinds of differences, and we’ve been presuming that these cells are all the same based on this one name, this one molecular marker. That’s been a problem. But the only way to solve it so we could study these cells was to look at intestinal stem cells at the single cell level, which had never been done before.”