The most comprehensive genetic map of oral stem cells to date provides new insights into the specialized developmental pathways of oral stem cells and opens the door to targeted regenerative medicine and interventions, such as therapies to grow bone. Researchers at the ADA Forsyth Institute and the University of North Carolina at Chapel Hill used single-cell transcriptome analysis to examine two populations of stem cells derived from extracted wisdom teeth and comprehensively map their genomes.
They discovered key and unexpected differences in two types, dental pulp stem cells (DPSC) and periodontal ligament stem cells (PDLSC), providing a new plan of attack for research into regenerative tissue.
"Both dental pulp stem cells and periodontal ligament stem cells have the potential to develop into any type of cell in the body," explains Alpdogan Kantarci of ADA Full Sail. "We wanted to find out how they differ and whether there are differences in their ability to differentiate into other cell types."
The study found that each of the two cell types has seven different gene clusters, and within these gene clusters, different categories of genes are involved in specific stages of differentiation. Of these gene clusters, four were similar in both types of cells, but three were significantly different. The unique PDLSC cluster resembles fibroblasts, cells that can differentiate to form connective tissue, while the DPSC cluster has a higher differentiation potential and is more likely to transform into osteoblasts, cells that form new bone or repair existing bone.
"New information about the specific genetic makeup and differentiation mechanisms of dental pulp and periodontal ligament stem cells will usher in a new era of regenerative medicine work. It will be possible to select stem cells based on their unique properties to create targeted regenerative dental tissue repair and other regenerative therapies."
Unlike other stem cell studies, wisdom tooth cells were extracted without culture and subjected to single-cell transcriptome analysis at UNU. The team also differentiated the two cells into fibroblasts and osteoblasts.
By identifying that the genetic makeup of the DPSC clusters makes them more prone to osteoblast differentiation, the team believes they have unlocked another clue to using stem cell therapy to promote tooth regeneration.
"Prior to this study, it was thought that stem cells were either very similar to each other or very different from each other," Kantarci said. "Now we have enough information to see the huge potential of harnessing the specific characteristics of these stem cells to create more effective and targeted regenerative therapies."
The research was published in the Journal of Dental Research.