Fighting Paralysis: Cells that Enable Sensation Created for the First Time


Researchers from UCLA create cells which enable the sense of touch. The process  could become a huge step towards restoring sensation in people suffering from paralysis.

Researchers from UCLA, have for the first time coaxed human stem cells into becoming sensory interneurons, the cells which enable the sense of touch. The study could be a huge step towards therapies to restore sensation in people suffering from paralysis. 

The investigation was led by Samantha Butler, associate professor of neurobiology at UCLA and member of the Broad Stem Cell Research Center.

Sensory interneurons, are found in the spinal cord and are responsible for transmitting information from the outer body or periphery, into the central nervous system. It is this system which enables the sense of touch. 

People who suffer from paralysis are greatly affected by a deficient sense of touch, which can make them unable to feel pain. This is a dangerous situation, since pain is an important part of the body’s defense mechanism. Without the feeling of pain, we could get burned by a hot surface or cut by a sharp knife whilst cooking, and we wouldn’t even know about it. 

"The field has for a long time focused on making people walk again," said Samantha Butler. "Making people feel again doesn't have quite the same ring. But to walk, you need to be able to feel and to sense your body in space; the two processes really go hand in glove." She added.

In a different study published in September, Butler and her associates determined how signals from a family of proteins influenced the development of sensory interneurons in chicken embryos. The research of the study is currently being applied to human stem cells.

They added a specific protein and retinoic acid to human embryonic cells, and obtained a mixture of two types of sensory interneurons. DI1 sensory interneurons, which give people the sense of the body being in space; DI3 sensory interneurons which enable them to feel pressure. 

The researchers discovered that a matching mixture of sensory interneurons were generated when they added the same molecules to induced pluripotent stem cells, a type of cell which is a produced by reprogramming a patient’s own mature cells such as skin cells. 

The reprogramming technique produces stem cells able to generate any type of cell whilst maintaining the person’s original genetic code. Being able to produce sensory interneurons with the patient’s genetic code, offers substantial potential towards the inception of a cell-based treatment which can restore the sense of touch without immune suppression. 

Butler now aims to create each type of interneuron separately, which would allow to fully understand the role of each cell type. This would allow scientists to start using the cells in clinical trials for paralysis. 

The study aims to reveal the factors which make stem cells produce other types of sensory interneurons is still underway. 

The research group is currently testing the sensory interneurons in mice. They want to investigate if the cells become fully functional and integrate with the nervous system. 

"We haven't solved how to restore touch but we've made a major first step by working out some of these protocols to create sensory interneurons." Claims Butler.

The research was supported by grants from the California Institute for Regenerative Medicine and its Cal State Northridge-UCLA Bridges to Stem Cell Research program, the National Institutes of Health and the UCLA Broad Stem Cell Research Center.

Story Source:  Materials provided by University of California – Los Angeles Health Sciences. Original written by Sarah C.P. (Content may be edited for style Photo Credit: Karim Ghantous  (The photograph provided bears no relation to the study.)