Ultrasonography-guided transplantation facilitates perineural delivery of stem cells

Treatment options for peripheral neuropathy are very limited. In order to develop a therapeutic strategy using stem cell therapy for the peripheral nervous system, we explored the feasibility of a new delivery method. Using ultrasonography-guided transplantation, human mesenchymal stem cells (hMSCs) were delivered into the perineural region of small rodent models. An optical imaging system revealed that hMSCs stained with CFSE or PKH26 reside for a week post-transplantation in both the mouse and rat. Immunofluorescence analysis of tissues revealed the presence of transplanted hMSCs in the perineural region of mice. At the end of the experiments, no behavioral or phenotypic abnormalities were observed. In addition, H&E and toluidine blue staining showed the integrity of the sciatic nerve after transplantation. This is the first study, to the best of our knowledge, to deliver cells into the perineural region under ultrasonography guidance. Since hMSCs can reside for a considerable time at a transplanted site, an anti-inflammatory efficacy of the transplanted hMSCs can be expected in the perineural region. In conclusion, we established a new administration route for inflammatory peripheral neuropathy without complications, and this may be used for delivery of chemical drugs or stem cells.