Enhancement of regeneration with glia cell line-derived neurotrophic factor-transduced human amniotic fluid mesenchymal stem cells after sciatic nerve crush injury.
OBJECTIVE
Human amniotic fluid-derived mesenchymal stem cells (AFMSCs) have been shown to promote peripheral nerve regeneration, and the local delivery of neurotrophic factors may additionally enhance nerve regeneration capacity. The present study evaluates whether the transplantation of glia cell line-derived neurotrophic factor (GDNF)-modified human AFMSCs may enhance regeneration of sciatic nerve after a crush injury.


METHODS
Peripheral nerve injury was produced in Sprague-Dawley rats by crushing the left sciatic nerve using a vessel clamp. Either GDNF-modified human AFMSCs or human AFMSCs were embedded in Matrigel and delivered to the injured nerve. Motor function and electrophysiological studies were conducted after 1 and 4 weeks. Early or later nerve regeneration markers were used to evaluate nerve regeneration. The expression of GDNF in the transplanted human AFMSCs and GDNF-modified human AFMSCs was monitored at 7-day intervals.


RESULTS
Human AFMSCs were successfully transfected with adenovirus, and a significant amount of GDNF was detected in human AFMSCs or the culture medium supernatant. Increases in the sciatic nerve function index, the compound muscle action potential ratio, conduction latency, and muscle weight were found in the groups treated with human AFMSCs or GDNF-modified human AFMSCs. Importantly, the GDNF-modified human AFMSCs induced the greatest improvement. Expression of markers of early nerve regeneration, such as increased expression of neurofilament and BrdU and reduced Schwann cell apoptosis, as well as late regeneration markers, consisting of reduced vacuole counts, increased expression of Luxol fast blue and S100 protein, paralleled the results of motor function. The expression of GDNF in GDNF-modified human AFMSCs was demonstrated up to 4 weeks; however, the expression decreased over time.


CONCLUSIONS
The GDNF-modified human AFMSCs appeared to promote nerve regeneration. The consecutive expression of GDNF was demonstrated in GDNF-modified human AFMSCs up to 4 weeks. These findings support a nerve regeneration scenario involving cell transplantation with additional neurotrophic factor secretion.
Cheng
Fu-Chou
FC
Stem Cell Center, Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan.
Tai
Ming-Hong
MH
Sheu
Meei-Ling
ML
Chen
Chun-Jung
CJ
Yang
Dar-Yu
DY
Su
Hong-Lin
HL
Ho
Shu-Peng
SP
Lai
Shu-Zhen
SZ
Pan
Hung-Chuan
HC
D000256:Adenoviridae / Q000235:genetics; D000653:Amniotic Fluid / Q000166:cytology*; D000818:Animals; D002478:Cells, Cultured; D004195:Disease Models, Animal; D004594:Electrophysiology; D051100:Glial Cell Line-Derived Neurotrophic Factor / Q000235:genetics*; D006801:Humans; D020287:In Situ Nick-End Labeling; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000473:pathology; D009409:Nerve Crush; D009416:Nerve Regeneration / Q000502:physiology*; D009929:Organ Size; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000473:pathology / Q000502:physiology; D020426:Sciatic Neuropathy / Q000473:pathology / Q000628:therapy*; D013525:Surgical Instruments; D014161:Transduction, Genetic
D051100:Glial Cell Line-Derived Neurotrophic Factor