Previous research has shown that different concentrations of bone morphogenetic proteins (BMPs) correlated with the formation of different categories of sensory interneurons. However, in this new study, a team from the University of California, Los Angeles found that a specific type BMP will always lead to the same category of sensory interneuron, regardless of concentration. The paper was published yesterday and can be found in eLife.
In their study, they found that increasing the concentration of a certain type of BMP will make more of the same kinds of sensory interneuron, but will not create a completely different category of sensory interneuron.
The team applied their findings to mouse embryonic stem cells in lab dishes and found that when adding specific types of BMPs, they were able to influence the stem cells to create two different categories of spinal sensory interneurons. These spinal sensory interneurons are ones that control the sensation of the position of the body in space and body movements are activated by touch, like flinching.
"Central nervous system injuries and diseases are particularly devastating because the brain and spinal cord are unable to regenerate," said Madeline Andrews, a predoctoral student in Samantha Butler's lab during the time of this research and first author of the study. "Replacing damaged tissue with sensory interneurons derived from stem cells is a promising therapeutic strategy. Our research, which provides key insights into how sensory interneurons naturally develop, gets us one step closer to that goal."
Butler's team is now looking for applying their findings to human stem cells and drug testing platforms that target diseases sensory interneurons. They also hope to investigate the feasibility of using sensory interneurons in cellular replacement therapies that may one day restore sensation to paralyzed patients.
Image: Increasing the concentration of a certain type of BMP increases the production of the same categories of sensory interneurons (red and green). Left: no BMP added; center: 1x BMP added; right: 10x BMP added. Image courtesy of UCLA Broad Stem Cell Research Center/eLife.