Scientists use low powered laser to grow teeth.
Scientists have used a low powered laser to activate and direct stem cells to grow teeth. It looks as if they did it right in the mouth (of a couple of species)! That’s a disruptive innovation compared to the way stem cells are typically grown and developed outside the body.
The big problem currently is guiding stem cells to turn into the type of cells you want them to be. You just can’t inject stem cells into the body and know that they will become the cells you are missing. It’s complicated making them do what you want them to do. This technique stimulates the growth of stem cells in the body and the automatically pick up clues as to what type of cells to become. This could make some stem cell procedures become routine, and as inexpensive as filling a cavity. Nice if this works for other parts of the body.
Rapid advancements in the field of stem cell biology have led to many current efforts to exploit stem cells as therapeutic agents in regenerative medicine. However, current ex vivo cell manipulations common to most regenerative approaches create a variety of technical and regulatory hurdles to their clinical translation, and even simpler approaches that use exogenous factors to differentiate tissue-resident stem cells carry significant off-target side effects. We show that non-ionizing, low-power laser (LPL) treatment can instead be used as a minimally invasive tool to activate an endogenous latent growth factor complex, transforming growth factor–β1 (TGF-β1), that subsequently differentiates host stem cells to promote tissue regeneration. LPL treatment induced reactive oxygen species (ROS) in a dose-dependent manner, which, in turn, activated latent TGF-β1 (LTGF-β1) via a specific methionine residue (at position 253 on LAP). Laser-activated TGF-β1 was capable of differentiating human dental stem cells in vitro. Further, an in vivo pulp capping model in rat teeth demonstrated significant increase in dentin regeneration after LPL treatment. These in vivo effects were abrogated in TGF-β receptor II (TGF-βRII) conditional knockout (DSPPCreTGF-βRIIfl/fl) mice or when wild-type mice were given a TGF-βRI inhibitor. These findings indicate a pivotal role for TGF-β in mediating LPL-induced dental tissue regeneration. More broadly, this work outlines a mechanistic basis for harnessing resident stem cells with a light-activated endogenous cue for clinical regenerative applications.
Photo credit: GB Times