Enhanced regeneration in injured sciatic nerve by human amniotic mesenchymal stem cell.
OBJECTIVE
Amniotic fluid mesenchymal stem cells (MSCs) have the potential to differentiate into neuronal stem cells in vitro. We evaluated using amniotic fluid MSCs to support or enhance the ability of the injured sciatic nerve to cross a nerve gap.


METHODS
We created a 5 mm nerve defect in Sprague Dawley rats. One group received therapy with MSCs embedded into woven oxidised regenerated cellulose gauze (Surgical; Ethicon, Somerville, NJ) and fibrin glue, while a control group received woven Surgicel and fibrin glue only. Evaluation methods included behavioural, electrophysiological and immunohistochemical studies.


RESULTS
In gait analysis, the angle of the ankles in the treatment and control group were 46.4 degrees (standard deviation [SD]=15 degrees) and 36 degrees (SD=8.2 degrees), respectively, which was statistically significant (p=0.045). Five of 10 treated rats (50%) demonstrated partial foot movement, while none of the control group had any movement. The percentage amplitude of muscle compound action potential in the experimental group was 43% (SD=12.5%) compared to 29% (SD=8.8%) in the control group (p=0.038). The conduction latencies in the control and experimental groups was 2.5 ms (SD=0.45) and 1.7 ms (SD=0.47), respectively (p=0.005). Histological examination demonstrated that 70% of the treatment group achieved a maximum axon diameter percentage across the nerve gap of greater than 50%, compared with 0% in the control group. There were no differences in direction of fibre growth and fibrotic reaction between the two groups.


CONCLUSIONS
Amniotic fluid MSC can augment growth of injured nerve across a nerve gap. This effect may be due to neurotrophic or induction effects of the MSC interacting with Schwann cells. Further study is required to determine the underlying mechanism of this effect.
Pan
Hung-Chuan
HC
Department of Medical Research, Taichung Veterans General Hospital, Taichung, (40705), Taiwan, ROC.
Yang
Dar-Yu
DY
Chiu
Yung-Tsung
YT
Lai
Shu-Zhen
SZ
Wang
Yeou-Chih
YC
Chang
Ming-Hong
MH
Cheng
Fu-Chou
FC
D000650:Amnion / Q000166:cytology / Q000637:transplantation*; D000818:Animals; D002478:Cells, Cultured; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology*; D009416:Nerve Regeneration / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020426:Sciatic Neuropathy / Q000473:pathology / Q000601:surgery*; D033581:Stem Cell Transplantation / Q000379:methods*