• 대한수의학회지
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• 제44권4호
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• pp.483-486
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• 2004

The expression of nestin and vimentin in the spinal nerve roots of rats with experimental autoimmune encephalomyelitis (EAE) was studied to ascertain whether Schwann cells in the peripheral nerves respond to acute central nervous system autoimmune injury. Immunohistochemistry demonstrated that nestin was constitutively expressed in the dorsal roots of spinal nerves in control rats; its expression was enhanced in the spinal nerve roots of rats with EAE. Vimentin expression was weak in control rat spinal nerve roots, and it was increased in the dorsal roots of rats with EAE. It is postulated that normal animals have multipotent progenitor cells that constitutively express nestin and vimentin in the spinal nerve roots. In response to an injury of the central nervous system, these multipotent Schwann cells are activated in the spinal nerve roots through the expression of the intermediate filament proteins vimentin and nestin.

• 혜화의학회지
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• 제14권1호
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• pp.201-211
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• 2005

Cdc2 kinase is a prototypical cyclin-dependent kinase critical for G2 to M phase cell cycle transition. Yet, its function in the nervous system is largely unknown. Here, we investigated possible role of Cdc2 in axonal regeneration using sciatic nerve system in rat. Cdc2 protein levels and activity were increased in the injured sciatic nerves 3 and 7 days after crush injury and then decreased to basal level 14 days later. Administration of Cdc2 kinase inhibitor roscovitine in vivo at the time of crush injury significantly inhibited axonal regeneration when regrowing axons were analyzed using retrograde tracers. Cdc2 protein levels in cultured Schwann cells which were prepared from sciatic nerves 7 days after crush injury were much higher compared with those from uninjured sciatic nerves, suggesting that Cdc2 protein expression was primarily induced in the Schwann cells. To further investigate Cdc2 function in Schwann cell, we examined changes in cultured Schwann cell proliferation and migration in culture system. Both the number of proliferating Schwann cells and the extent of neurite outgrowth from co-cultured DRG neurons were significantly decreased by Cdc2 inhibitor roscovitine treatment in DRG culture which was prepared from animals with sciatic nerve injury for 7 days. Also, Schwann cell migration in the injured sciatic nerve explant was significantly inhibited by roscovitine treatment. Taken together, the present data suggest that Cdc2 may be involved in peripheral nerve regeneration via Schwann cell proliferation and migration.

• 통합자연과학논문집
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• 제15권3호
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• pp.123-129
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• 2022

Schwann cells play a critical role for myelination in peripheral nerve system. It also plays an important role in nerve protection and regeneration. In peripheral nerve damage, regeneration is induced by the migration and proliferation of Schwann cells which were promoted by suppressing the oxidative stress. In this study, Human placental extract was prepared by homogenization and estimated its efficacy in RSC96 cells. Placental extract exhibited a protective effect against hydrogen peroxide-induced oxidative stress in RSC96 cells, confirmed by MTT assay. Furthermore, placental extract decreased intracellular ROS against oxidative stress, confirmed by DCFH-DA assay. Autophagy was visualized with Cyto-ID staining to confirm the autophagy activity of placental extracts. The activity of autophagy was confirmed by immunoblot analysis of autophagy flux-associated proteins such as LC3 conversion and SQSTM1 degradation. Thus, we confirmed the antioxidant effect of placental extract to protect RSC96 cells from oxidative stress, and observed that it activated autophagy and restored autophagy flux.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권2호
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• pp.100-107
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• 2004

Schwann cell, one of important components of peripheral nervous system, interact with neurons to mutually support the growth and replication of embryonal nerves and to maintain the different functions of adult nerves. The Ara-C, known as an antimitotic agent, have been used to have high effectiveness in eliminating fibroblasts during Schwann cell culture period. This enrichment effect is also known to be cummulative with each successive pulse of Ara-C applied and is due to a progressive loss of fibroblasts. But the cytotoxicity by Ara-C is also cummulative and noticeable over the period. To determine the most effective application time and interval of Ara-C in the Schwann cell culture, we observed the Schwann cell purity and density with the Ara-C treatment in plain and three-dimensional culture from dorsal root ganglion of new born rat. By culturing dispersed dorsal root ganglia, we can repeatedly generate homogenous Schwann cells, and cellular morphology and cell count with mean percentages were evaluated in the plain culture dishes and in the immunostainings of S-100 and GFAP in the three-dimensional culture. The Ara-C treated cultures showed a higher Schwann cell percentage ($31.0%{\pm}8.09%$ in P4 group to $65.5%{\pm}24.08%$ in P2 group), compared with that obtained in the abscence of Ara-C ($17.6%{\pm}6.03%$) in the plain culture after 2 weeks. And in the three-dimensional culture, S-100 positive cells increased to $56.22%{\pm}0.67%$ and GFAP positive cells to $66.46%{\pm}1.83%$ in G2 group (p<0.05), higher yield than other groups with Ara-C application. Therefore, we concluded that the Ara-C treatment is effective for the proliferation of Schwann cells contrast to the fibroblasts in vitro culture, and the first application after 24 hours from cell harvesting and subsequent 2 pulse treatment (P2 group in plain culture and G2 group in three-dimensional culture) was more effective than other application protocols.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권1호
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• pp.42-51
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• 2006

Schwann cell, one of important components of peripheral nervous system, interact with neurons to mutually support the growth and replication of embryonal nerves and to maintain the different functions of adult nerves. The Ara-C, known as an antimitotic agent, have been used to have high effectiveness in eliminating fibroblasts during Schwann cell culture period. This enrichment effect is also known to be cummulative with each successive pulse of Ara-C applied and is due to a progressive loss of fibroblasts. But the cytotoxicity by Ara-C is also cummulative and noticeable over the period. To determine the most effective application time and interval of Ara-C in the Schwann cell culture, we observed the Schwann cell purity and density with the Ara-C treatment in plain and three-dimensional culture from dorsal root ganglion of new born rat. By culturing dispersed dorsal root ganglia, we can repeatedly generate homogenous Schwann cells, and cellular morphology and cell count with mean percentages were evaluated in the plain culture dishes and in the immunostainings of S-100 and GFAP in the three-dimensional culture. The Ara-C treated cultures showed a higher Schwann cell percentage (31.0%${\pm}$8.09% in P4 group to 65.5%${\pm}$24.08% in P2 group), compared with that obtained in the abscence of Ara-C (17.6%${\pm}$6.03%) in the plain culture after 2 weeks. And in the three-dimensional culture, S-100 positive cells increased to 56.22%${\pm}$0.67% and GFAP positive cells to 66.46%${\pm}$1.83% in G2 group (p<0.05), higher yield than other groups with Ara-C application. Therefore, we concluded that the Ara-C treatment is effective for the proliferation of Schwann cells contrast to the fibroblasts in vitro culture, and the first application after 24 hours from cell harvesting and subsequent 2 pulse treatment (P2 group in plain culture and G2 group in three-dimensional culture) was more effective than other application protocols.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권6호
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• pp.465-473
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• 2004

Purpose : The essential triad for nerve regeneration is nerve conduit, supporting cell and neurotrophic factor. In order to improve the peripheral nerve regeneration, we used polyglycolic acid(PGA) tube and brain-derived neurotrophic factor(BDNF) gene transfected Schwann cells in sciatic nerve defects of SD rat. Materials and methods : Nerve conduits were made with PGA sheet and outer surface was coated with poly(lactic-co-glycolic acid) for mechanical strength and control the resorption rate. The diameter of conduit was 1.8mm and the length was 17mm Schwann cells were harvested from dorsal root ganglion(DRG) of SD rat aged 1 day. Schwann cells were cultured on the PGA sheet to test the biocompatibility adhesion of Schwann cell. Human BDNF gene was obtained from cDNA library and amplified using PCR. BDNF gene was inserted into E1 deleted region of adenovirus shuttle vector, pAACCMVpARS. BDNF-adenovirus was multiplied in 293 cells and purified. The BDNF-Adenovirus was then infected to the cultured Schwann cells. Left sciatic nerve of SD rat (250g weighing) was exposed and 14mm defects were made. After bridging the defect with PGA conduit, culture medium(MEM), Schwann cells or BDNF-Adenovirus infected Schwann cells were injected into the lumen of conduit, respectively. 12 weeks after operation, gait analysis for sciatic function index, electrophysiology and histomorphometry was performed. Results : Cultured Schwann cells were well adhered to PGA sheet. Sciatic index of BDNF transfected group was $-53.66{\pm}13.43$ which was the best among three groups. The threshold of compound action potential was between 800 to $1000{\mu}A$ in experimental groups which is about 10 times higher than normal sciatic nerve. Conduction velocity and peak voltage of action potential of BDNF group was the highest among experimental groups. The myelin thickness and axonal density of BDNF group was significantly greater than the other groups. Conclusion : BDNF gene transfected Schwann cells could regenerate the sciatic nerve gap(14mm) of rat successfully.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 추계학술대회
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• pp.448-451
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• 2018

본 연구는 뉴런 세포와 슈반 세포의 공동 배양에 의한 수초화 발생 과정과 herpes simplex virus-1 감염에 의한 탈수초화 발생과정을 전자 현미경과 분자생물학적 분석에 의하여 확인하고자 하였다. 쥐의 배아로부터 후근신경절(dorsal root ganglion, DRG)을 분리하여 슈반(Schwann) 세포와 뉴런 세포(neuronal cell)를 in vitro에서 각각 배양하였다. 유사 분열 억제인자로 처리한 뉴런세포와 정제된 슈반세포를 함께 공동 배양을 하여 수초화를 발생시켰다. 이렇게 수초화된 공동 배양 세포에 herpes simplex virus-1를 감염시켜 탈수초화를 진행시켰다. 수초 형성의 존재를 의미하는 myelin protein zero(MPZ) 항체를 사용하고 전자 현미경을 이용하여 수초 발생 및 탈수초화 과정을 관찰하였다.

• 한국정보통신학회논문지
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• 제21권6호
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• pp.1212-1217
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• 2017

척수신경절의 신경 세포와 슈반세포의 공동 배양으로 수초화 형성 세포 집단이 제조되었다. 슈반세포와 뉴런 세포가 쥐의 배아의 척수신경절로 부터 각각 in vitro에서 분리되었다. 배양된 슈반세포와 뉴런 세포는 동일한 평판접시에서 공동배양 되었다. 본 실험과정은 다음과 같은 4 단계로 구성되어 있다 : 첫 번째 단계는 배아의 척수 신경절 세포의 현탁 과정, 두 번째 단계는 안티 mitotic cocktail의 추가 과정, 세 번째 단계는 척수신경절 세포의 정제 과정, 및 네 번째 단계는 척추 신경절 세포에 슈반 세포의 추가 과정이다. 이들 세포들은 때 수초화가 진행되었다. 이렇게 수초화된 공동 배양은 Semliki forest virus에 의해 감염되었고 그 때 탈수초화 과정을 유발시켰다. 우리는 수초화된 뉴런에 존재하는 peripheral myelin protein 22의 항체를 이용하여 수초화 과정과 탈수초화 과정을 확인하였다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권1호
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• pp.1-16
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• 2004

The use of artificial nerve conduit containing viable Schwann cells is one of the most promising strategies to repair the peripheral nerve injury. To fabricate an effective nerve conduit whose microstructure and internal environment are more favorable in the nerve regeneration than existing ones, a new three-dimensional Schwann cell culture technique using $Matrigel^{(R)}$. and dorsal root ganglion (DRG) was developed. Nerve conduit of three-dimensionally arranged Schwann cells was fabricated using direct seeding of freshly harvested DRG into a $Matrigel^{(R)}$ filled silicone tube (I.D. 1.98 mm, 14 mm length) and in vitro rafting culture for 2 weeks. The nerve regeneration efficacy of three-dimensionally cultured Schwann cell conduit (3D conduit group, n=6) was assessed using SD rat sciatic nerve defect of 10 mm, and compared with that of silicone conduit filled with $Matrigel^{(R)}$ and Schwann cells prepared from the conventional plain culture method (2D conduit group, n=6). After 12 weeks, sciatic function was evaluated with sciatic function index (SFI) and gait analysis, and histomorphology of nerve conduit and the innervated tissues of sciatic nerve were examined using image analyzer and electromicroscopic methods. The SFI and ankle stance angle (ASA) in the functional evaluation were $-60.1{\pm}13.9$, $37.9^{\circ}{\pm}5.4^{\circ}$ in 3D conduit group (n=5) and $-87.0{\pm}12.9$, $32.2^{\circ}{\pm}4.8^{\circ}$ in 2D conduit group (n=4), respectively. And the myelinated axon was $44.91%{\pm}0.13%$ in 3D conduit group and $13.05%{\pm}1.95%$ in 2D conduit group to the sham group. In the TEM study, 3D conduit group showed more abundant myelinated nerve fibers with well organized and thickened extracellular collagen than 2D conduit group, and gastrocnemius muscle and biceps femoris tendon in 3D conduit group were less atrophied and showed decreased fibrosis with less fatty infiltration than 2D conduit group. In conclusion, new three-dimensional Schwann cell culture technique was established, and nerve conduit fabricated using this technique showed much improved nerve regeneration capacity than the silicone tube filled with $Matrigel^{(R)}$ and Schwann cells prepared from the conventional plain culture method.

• 대한수의학회지
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• 제34권4호
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• pp.801-804
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• 1994

본 실험에서 초산납 투여로 인한 실험초기에 관찰할 수 있는 신경독성은 Schwann 세포의 종창이었다. 종창의 정도를 계측하기 위해 각 실험군 rat의 좌골신경을 횡단 조직표본으로 제작하여 Schwann세포의 두께와 핵의 장경을 측정 비교하였다. 즉 제1실험군은 30일간 0.5% 초산납이 함유된 음료수를 공급하였고 제2실험군은 제1군과 동일한 처리후 일반 실험실 조건에서 30일간 회복되게 하였으며 제3군은 대조군으로 정상 사육하였다. 초산납을 투여한 제1실험에서는 Schwann세포의 두께가 대조군보다 유의한 증가치를 보였는데, 제2실험군은 대조군과 유의한 차이가 없었다. Schwann세포핵의 직경 역시 제1군이 대조군보다 증가되었으나 유의한 차이는 없었다.