Prenatal repair of myelomeningocele with aligned nanofibrous scaffolds-a pilot study in sheep

Abstract

Background/purpose: Spinal cord damage in myelomeningocele (MMC) results from abnormal cord development and subsequent local trauma. Prenatal surgery prevents additional neural injury. However, existing damage is not reversed. Biodegradable nanofibrous scaffolds (NSs) promote regeneration of neural tissues. They mimic the microtopography of the extracellular matrix and guide tissue formation and organization. The purpose of this pilot study was to evaluate the practicality and safety of using biodegradable NS as a regenerative device in prenatal MMC repair.

Methods: Two fetal lambs underwent a surgically induced MMC defect followed by open fetal repair using aligned biodegradable NS. Lambs were killed at day 138. Spinal cords were examined for inflammation or fibrosis and stained for spinal cord architecture, myelin, and neuron cell bodies.

Results: Prenatal repair with NS demonstrated technical feasibility. There was no evidence of a surrounding inflammatory response or foreign-body reaction to the scaffold.

Conclusion: Biodegradable NS can be used surgically for the prenatal repair of MMC in a large animal model and does not appear to elicit an inflammatory or fibrotic reaction in fetal tissue. Further studies will determine their potential for neural cell infiltration, delivery of growth factors, drugs or stem cells, and functional recovery greater than standard repair.