TrackerSci is a new tool for tracking brain cell development and aging, offering fresh insights into cellular changes over a lifetime and potential applications in various organ studies.
How this process unfolds, however, has been largely unknown, both because of technological limitations and cell rarity. Finding progenitor cells in the brain is a needle-in-haystack endeavor; in mammals, they account for a mere .5 percent of all brain cells. That number drops to .1 percent in later stages of life—a downward shift due to cellular instability, a core characteristic of disease and aging.
“We were able to quantify cellular proliferation and differentiation rates of many cell types across the entire brain in a single experiment, which wasn’t possible using conventional approaches,” Cao says. “Those only capture static information—the current molecular state of a cell at a single moment. But TrackerSci captures dynamic information over time. It’s like other methods take snapshots, and we shoot a film.
The opposite is true in the elderly brain. Progenitor cells rarely become either neurons or glial cells; in fact, virtually every type of brain cell plummets. Most lost are dentate gyrus neuroblasts, which are essential for creating neurons in the hippocampus, a region linked to memory and diseases like. In comparison to the adult brain, the number of these cells drops by 16-fold in the elderly brain.