Exosome-mediated Neuroprotection Investigated in Spina Bifida

Researchers on the path to finding a cure for spina bifida have identified specific elements in stem cell secretions as key to protecting neurons and ultimately reducing the lower-limb paralysis associated with the birth defect.

Aijun Wang has identified stem cell byproducts that protect neurons.

Those elements are exosomes — vesicles that transfer molecules from cell to cell — and a small carbohydrate-binding protein known as galectin 1.

The team will use the results to optimize the neuroprotective qualities of a stem cell treatment they developed to improve the mobility issues associated with spina bifida.

Published in The FASEB Journal, the study was led by Aijun Wang, co-director of the UC Davis Health Surgical Bioengineering Laboratory.

Altering the outcomes of spina bifida

UC Davis Health fetal surgeon and study co-author Diana Farmer first showed that prenatal surgery reduces neurological defects in children with spina bifida, which occurs when the spinal cord does not properly close before birth. Children with the condition experience a range of lifelong cognitive, urological, musculoskeletal and motor disabilities.

Farmer and Wang, her chief collaborator, later showed that prenatal surgery combined with human placenta-derived mesenchymal stromal cells (PMSCs) improved hind limb control in animal models of spina bifida.

“We wanted to know the specific mechanisms of action of the PMSC treatment that protect neurons,” Wang said. "Our new results provide evidence that stem cell secretions containing exosomes that express galectin 1 are an important part of the therapeutic benefits and give us a path for optimizing the neuroprotective qualities of the treatment."

Hope for a cell-free treatment

The new study also could help the researchers produce a cell-free treatment for spina bifida and other spinal cord injuries based on byproducts of stem cells rather than the stem cells themselves, according to Wang.

Stem cells can heal, however they also can influence the broader immune system and treatment site, making the possibility of cell-free treatment highly attractive.

“Stem cell secretions can have the same or similar healing qualities, but also are a more stable and controllable product,” Wang said. “We are excited about what we see so far and are anxious to further explore the clinical applications of this research."

This article has been republished from materials provided by UC Davis Health. Note: material may have been edited for length and content. For further information, please contact the cited source.

Reference:

Kumar, P., Becker, J. C., Gao, K., Carney, R. P., Lankford, L., Keller, B. A., . . . Wang, A. (2019). Neuroprotective effect of placenta-derived mesenchymal stromal cells: Role of exosomes. The FASEB Journal. doi:10.1096/fj.201800972r