Effects of canine and murine mesenchymal stromal cell transplantation on peripheral nerve regeneration

Background and Objectives: Maintaining a permissive microenvironment is essential for adequate nerve regeneration. Cell-based therapy has the potential based cell replacement and promotion of axonal growth. The adipose tissue derived mesenchymal stromal cells (Ad-MSC) attract interest because neuroregenerative and anti-inflammatory properties. The aim of this study was to evaluate the effects of canine and murine Ad-MSC transplantation on the sciatic nerve regeneration. Methods: Forty Wistar rats were divided randomly into: control group - CG (n=8); denervated group - DG (n=8); decellularized vein group - VG (n=8); decellularized vein+canine MSC-cMSC (n=8); descellularized vein+murine MSC-mMSC (n=8). After 10-mm nerve gap, the tubulation technique was performed with decellularized vein filled with 106 MSC labeled with quantum dots (Qtracker 665®). The sciatic nerve functional index (SFI) and electroneuromyography (ENMG) measurements were carried and morphometric and immunohistochemistry analysis of the tissue. Results: The SFI values were higher in the cMSC and mMSC groups at day 27 (p < 0.020) and day 35 (p < 0.011). The ENMG analysis also revealed better results in the mMSC group. Density, number, and total area of the fibers were increased in the mMSC and cMSC groups. Brain-derived neurotrophic factor BDNF and S-100 protein positive immunoreactivity showed a higher expression for both in the nerve of the mMSC and cMSC groups. The MSC labeled with quantum dots were detected at day 35, indicating neuronal survival long after the nerve damage. Conclusions: Murine and canine Ad-MSC associated with decellularized vein scaffold had positive effects on sciatic nerve regeneration in rats.