Transplantation of uncultured omental adipose-derived stromal vascular fraction improves sciatic nerve regeneration and functional recovery through inside-out vein graft in rats.

Background: Despite presence of various nerve coaptation materials and techniques, achievement of desired functional peripheral nerve regeneration is still inadequate. Effects of transplantation of uncultured and uncharacterized stromal vascular fraction (SVF) from omental adipose tissue on peripheral nerve regeneration were studied using a rat sciatic nerve transection model.

Methods: A 10-mm sciatic nerve defect was bridged using an inside-out vein graft (IOVG) filled with SVF. In control group, the vein was filled with phosphate-buffered saline alone. The regenerated nerve fibers were studied 4 weeks, 8 weeks, and 12 weeks after surgery. In sham-operated group, the sciatic nerve was only exposed and manipulated.

Results: Functional study confirmed faster recovery of regenerated axons in IOVG/SVF than in IOVG group (p < 0.05). Gastrocnemius muscle mass in IOVG/SVF is found to be significantly more than that in IOVG group. Morphometric indices of the regenerated fibers showed that the number and diameter of the myelinated fibers were significantly higher in IOVG/SVF than in control group.In immunohistochemistry, location of reactions to S-100 in IOVG/SVF was clearly more positive than that in IOVG group.

Conclusions: SVF could be considered as a readily accessible source of stromal cells that improve functional recovery of sciatic nerve because of reduction in the interval from tissue collection until cell injection and simplicity of laboratory procedure, especially where atraumatic injury is dealt with.