지방조직 유래 줄기세포의 조골세포로의 분화에 대한 실험적 연구

이의석,장현석,권종진,임재석,Lee, Eui-Seok,Jang, Hyon-Seok,Kwon, Jong-Jin,Rim, Jae-Suk 대한악안면성형재건외과학회 2008 Maxillofacial Plastic Reconstructive Surgery Vol.30 No.2

Stem cells have self-renewal capacity, long-term viability, and multiline age potential. Adult bone marrow contains mesenchymal stem cells. Bone marrow-derived mesenchymal stem cells (BMSCs) are progenitors of skeletal tissue components and can differentiate into adipocytes, chondrocytes, osteoblasts, and myoblasts in vitro and undergo differentiation in vivo. However, the clinical use of BMSCs has presented problems, including pain, morbidity, and low cell number upon harvest. Recent studies have identified a putative stem cell population within the adipose tissue. Human adipose tissue contains pluripotent stem cells simillar to bone marrow-derived stem cells that can differentiate toward the osteogenic, adipogenic, myogenic, and chondrogenic lineages. Human adipose tissue-derived stem cells (ATSCs) could be proposed as an alternative source of adult bone marrow stem cells, and could be obtained in large quantities, under local anesthesia, with minimal discomfort. Human adipose tissue obtained by liposuction was processed to obtain ATSCs. In this study, we compared the osteogenic differentiation of ATSCs in a specific osteogenic induction medium with that in a non-osteogenic medium. ATSCs were incubated in an osteogenic medium for 28 days to induce osteogenesis respectively. Osteogenic differentiation was assessed by von Kossa and alkaline phosphatase staining. Expression of osteocyte specific bone sialoprotein, osteocalcin, collagen type I and alkaline phosphatase, bone morphogenic protein 2, bone morphogenic protein 6 was confirmed by RT-PCR. ATSCs incubated in the osteogenic medium were stained positively for von Kossa and alkaline phosphatase staining. Expression of osteocyte specific genes was also detected. Since this cell population can be easily identified through fluorescence microscopy, it may be an ideal source of ATSCs for further experiments on stem cell biology and tissue engineering. The present results show that ADSCs have an ability to differentiate into osteoblasts. In the present study, we extend this approach to characterize adipose tissue-derived stem cells.

고기능성 쌀단백질 소재 개발 연구

이의석(Eui-Suk Lee),김기종(Ki-Jong Kim),김재현(Jae-Hyeon Kim),홍순택(Soon-Taek Hong) 충남대학교 농업과학연구소 2010 농업과학연구 Vol.37 No.1

Rice bran proteins from different cultivars(Youngan, Sindongjin, Suwon 511) were extracted with Xylanase using orthogonal analysis method and their functional properties were investigated. The optimum extraction conditions, based on protein content in the extract found to be at 1 wt% xylanase, pH 7 and 50:1, solvent to rice bran ratio(v/w %). Nitrogen solubility indices(NSI) of rice bran protein concentrates were shown a minimum value at pH 4 ranged 2~23%, varied with different cultivars and a maximum (NSI≥90% for all cultivars) at pH 10. As for water adsorption and fat adsorption capacity, rice bran protein concentrates were shown to be better than Na-caseinate and isolated soy protein, respectively. Emulsifying activities were observed high in order of Na-caseinate>Youngan rice bran protein>Shindongjin rice bran protein>Suwon 511 rice bran protein>isolated soy protein. In general, the surface tension of rice bran protein solution(10?³ wt%, 5 mM bis-tris, pH 7) was increased with increasing concentrations and found a minimum value near pI. On heating, it was decreased slightly with increasing temperatures up to 70 ℃ and then increased above 80 ℃. Addition of sodium chloride was made the surface tension decrease. In conclusion, with Xylanase, rice bran protein concentrate can be successfully extracted from the rice bran of different cultivars and the Youngan rice bran protein was thought to have best functionality among rice cultivars tested. It might be used as a milk protein substitute.

초임계 CO2를 이용하여 추출한 탈지미강 중 표면활성물질의유화 성질 평가

이형주 ( Hyong Ju Lee ),배재석 ( Jae Suk Bae ),이의석 ( Eui Suk Lee ),강호철 ( Ho Cheol Kang ),이기택 ( Ki Teak Lee ),홍순택 ( Soon Taek Hong ) 한국산업식품공학회 2012 산업 식품공학 Vol.16 No.2

In this experiment, the surface-active substances were extracted from defatted rice bran and their emulsifying properties were investigated. The sample emulsions stabilized with the surface-active substances (3 fractions: 1-HS, 6- HS and 18-HS) were prepared and then their physico-chemical properties such as fat globule size, creaming stability, oil-off and dispersion stability were determined. It was found that the sample emulsion with different fraction of surface- active substances showed different physico-chemical properties from each other. Specially, 1-HS emulsion with the smallest particle size was evaluated to be superior to others in terms of higher creaming stability, low incidence of oil-off and higher dispersion stability. From the study of co-surfactant addition (Tween 20, SSL and GMS), GMS was found to be the most effective in reducing fat globule size in 1-HS emulsion. This indicated that there might be a co-operative adsorption of the two surface-active substances at the oil-water interface. Thus, the potentiality of the rice bran extracts, obtained with specific conditions, as natural surface-active substances was confirmed.

프랙탈 분석을 통한 악골 내 낭종의 감압술 후 골 치유에 대한 방사선학적 평가

백진우,석민,이의석,장현석,임재석,Baek, Jin-Woo,Seok, Min,Lee, Eui-Suk,Jang, Hyun-Seok,Rim, Jae-Suk 대한구강악안면외과학회 2007 대한구강악안면외과학회지 Vol.33 No.5

Purpose: This study was done to know the usefulness of fractal analysis when evaluating the radiologic changes after decompression on jaw bone cystic lesions using fractal analysis. Materials and methods: 30cases of cystic lesions were followed up after decompression. Panoramic image was used to observe radiologic changes around the cystic lesion. The part of the panoramic image which showed radiologic change was defined as region of interest(ROI); The fractal dimension of the ROI was calculated using box-counting method. Results: Using sign-rank test, there was a statistically significant difference in fractal dimensions after decompression therapy(P<0.0001). The fractal dimensions statistically increased after decompression(the median of D:0.12). Conclusions: The ROI after decompression showed higher fractal dimensions which offer the objective proof of the bone healing around cystic lesions after decompression treatment.

HA/TCP 골이식재상에 이식된 지방유래 줄기세포의 골모세포로의 분화 및 골형성에 대한 연구

임재석,권종진,장현석,이의석,정유민,이태형,박정균,Rim, Jae-Suk,Gwon, Jong-Jin,Jang, Hyon-Seok,Lee, Eui-Seok,Jeong, You-Min,Lee, Tai-Hyung,Park, Jeong-Kyun 대한악안면성형재건외과학회 2010 Maxillofacial Plastic Reconstructive Surgery Vol.32 No.2

Aim of the study: An alternative source of adult stem cells that could be obtained in large quantities, under local anesthesia, with minimal discomfort would be advantageous. Adipose tissue could be processed to obtain a fibroblast-like population of cells or adipose tissue-derived stromal cells (ATSCs). This study was performed to confirm the availability of ATSCs in bone tissue engineering. Materials amp; Methods: In this study, adipose tissue-derived mesenchymal stem cell was extracted from the liposuctioned abdominal fat of 24-old human and cultivated, and the stem cell surface markers of CD 105 and SCF-R were confirmed by immunofluorescent staining. The proliferation of bone marrow mesenchymal stem cell and ATSCs were compared, and evaluated the osteogenic differentiation of ATSCs in a specific osteogenic induction medium. Osteogenic differentiation was assessed by von Kossa and alkaline phosphatase staining. Expression of osteocyte specific BMP-2, ALP, Cbfa-1, Osteopontin and osteocalcin were confirmed by RT-PCR. With differentiation of ATSCs, calcium concentration was assayed, and osteocalcin was evaluated by ELISA (Enzyme-linked immunosorbant assay). The bone formation by 5-week implantation of HA/TCP block loaded with bone marrow mesenchymal stem cells and ATSCs in the subcutaneous pocket of nude mouse was evaluated by histologic analysis. Results: ATSCs incubated in the osteogenic medium were stained positively for von Kossa and alkaline phosphatase staining. Expression of osteocyte specific genes was also detected. ATSCs could be easily identified through fluorescence microscopy, and bone formation in vivo was confirmed by using ATSC-loaded HA/TCP scaffold. Conclusions: The present results show that ATSCs have an ability to differentiate into osteoblasts and formed bone in vitro and in vivo. So ATSCs may be an ideal source for further experiments on stem cell biology and bone tissue engineering.

Pleiotrophin이 골수 줄기 세포의 부착 및 골형성에 미치는 효과에 대한 연구

윤정호,윤정주,장현석,임재석,이의석,김대성,권종진,Yoon, Jung-Ho,Eune, Jung-Ju,Jang, Hyon-Seok,Rim, Jae-Suk,Lee, Eui-Seok,Kim, Dae-Sung,Kwon, Jong-Jin 대한악안면성형재건외과학회 2006 Maxillofacial Plastic Reconstructive Surgery Vol.28 No.2

An area of current research is investigating the app1ication of human mesenchymal stem cells or hMSCs as a cell-based regenerative therapy. In order to achieve effective bone regeneration, appropriate matrices functioning as cell-carriers must be identified and optimized in terms of function, efficacy and biocompatibility. Two methods of approaching optimization of matrices are to facilitate adhesion of the donor hMSCs and furthermore to facilitate recruitment of host progenitor cells to osteoblastic differentiation. Pleiotrophin is an extracellular matrix protein that was first identified in developing rat brains and believed to be associated with developing neuronal pathways. A recent publication by Imai and colleagues demonstrated that transgenic mice with upregulated pleiotrophin expression developed a greater volume of cortical as well as cancellous bone. The proposed mechanism of action of pleiotrophin is demonstrated here. Through either environmental stresses and/or intracellular regulation, there is an increase in pleiotrophin production. The pleiotrophin is released extracellularly into areas requiring bone deposition. A receptor-mediated process recruits host osteoprogenitor cells into these areas. Therefore, the aim of our study was to investigate the osteoconductive properties of pleiotrophin. We wanted to determine if pleiotrophin coating facilitates cellular adhesion and furthermore if this has any effect on hMSCs derived bone formation in an animal model. The results showed a dose dependent response of cellular adhesion in fibronectin samples, and cellular adhesion was facilitated with increasing pleiotrophin concentrations. Histologic findings taken after 5 weeks implantation in SCID mouse showed no presence of bone formation with only a dense fibrous connective tissue. Possible explanations for the results of the osteogenesis assay include inappropriate cell loading.

HSP27 EXPRESSION IN OSTEOBLAST BY THERMAL STRESS

임재석,김병렬,권종진,장현석,이의석,전상호,우현일,Rim, Jae-Suk,Kim, Byeong-Ryol,Kwon, Jong-Jin,Jang, Hyon-Seok,Lee, Eui-Suk,Jun, Sang-Ho,Woo, Hyeon-Il Korean Association of Maxillofacial Plastic and Re 2008 Maxillofacial Plastic Reconstructive Surgery Vol.30 No.1

Aim of the study: Thermal stress is a central determinant of osseous surgical outcomes. Interestingly, the temperatures measured during endosseous surgeries coincide with the temperatures that elicit the heat shock response of mammalian cells. The heat shock response is a coordinated biochemical response that helps to protect cells from stresses of various forms. Several protective proteins, termed heat shock proteins (hsp) are produced as part of this response. To begin to understand the role of the stress response of osteoblasts during surgical manipulation of bone, the heat shock protein response was evaluated in osteoblastic cells. Materials & methods: With primary cell culture studies and ROS 17/2.8 osteoblastic cells transfected with hsp27 encoding vectors culture studies, the thermal stress response of mammalian osteoblastic cells was evaluated by immunohistochemistry and western blot analysis. Results: Immunocytochemistry indicated that hsp27 was present in unstressed osteoblastic cells, but not fibroblastic cells. Primarily cultured osteoblasts and fibroblasts expressed the major hsp in response to thermal stress, however, the small Mr hsp, hsp27 was shown to be a constitutive product only in osteoblasts. Creation of stable transformed osteoblastic cells expressing abundant hsp27 protein was used to demonstrate that hsp27 confers stress resistance to osteoblastic cells. Conclusions: The demonstrable presence and function of hsp27 in cultured bones and cells implicates this protein as a determinant of osteoblastic cell fate in vivo.

PLLA/HA Composite Scaffold와 골수 줄기세포를 이용한 조직공학적 골재생에 대한 연구

김병렬,장현석,임재석,이의석,김동현,Kim, Byeong-Yol,Jang, Hyon-Seok,Rim, Jae-Suk,Lee, Eui-Seok,Kim, Dong-Hyun 대한악안면성형재건외과학회 2008 Maxillofacial Plastic Reconstructive Surgery Vol.30 No.4

Aim of the study: Scaffolds are crucial to tissue engineering/regeneration. Biodegradable polymer/ceramic composite scaffolds can overcome the limitations of conventional ceramic bone substitutes such as brittleness and difficulty in shaping. In this study, poly(L-lactide)/hydroxyapatite(PLLA/HA) composite scaffolds were fabricated for in vivo bone tissue engineering. Material & methods: In this study, PLLA/HA composite microspheres were prepared by double emulsion-solvent evaporation method, and were evaluated in vivo bone tissue engineering. Bone marrow mesenchymal stem cell from rat iliac crest was differentiated to osteoblast by adding osteogenic medium, and was mixed with PLLA/HA composite scaffold in fibrin gel and was injected immediately into rat cranial bone critical size defect(CSD:8mm in diameter). At 1. 2, 4, 8 weeks after implantation, histological analysis by H-E staining, histomorphometric analysis and radiolographic analysis were done. Results: BMP-2 loaded PLLA/HA composite scaffolds in fibrin gel delivered with osteoblasts differentiated from bone marrow mesenchymal stem cells showed rapid and much more bone regeneration in rat cranial bone defects than control group. Conclusion: This results suggest the feasibility and usefulness of this type of scaffold in bone tissue engineering.

PLEIOTROPHIN (PTN) EXPRESSION IN OSTEOBLASTIC CELLS

김병렬,임재석,권종진,장현석,이의석,전상호,김영진,Kim, Byeong-Yol,Rim, Jae-Suk,Kwon, Jong-Jin,Jang, Hyon-Seok,Lee, Eui-Seok,Jun, Sang-Ho,Kim, Young-Jin Korean Association of Maxillofacial Plastic and Re 2007 Maxillofacial Plastic Reconstructive Surgery Vol.29 No.6

Pleiotrophin or osteoblast-specific factor 1(HOSF-1) is a growth-associated protein present in bone matrix. This study was designed to study pleiotrophin expression in osteoblastic cells. Pleiotrophin was expressed by osteoblast-like cell line. Pleiotrophin expression increased following the proliferative phase and was minimal at the terminal phases of the induced differentiation of cultured MC3T3-E1 cells. Pleiotrophin expression represents another autocrine factor that may contribute to the physiologic control of induced bone formation. In this study, induced osteogenesis will be examined in the context of the osteoblast expression of and regulation by PTN. I hypothesized that PDGF-BB stimulation of PTN expression represents an important paracrine signal during the induced osteogenesis associated with periodontal and implant surgeries. The possible mediation by PTN of anabolic effects attributed to PDGF-BB stimulation was examined in cell culture models of osteoblast differentiation. These studies will contribute fundamental insights to osteoblast biology and insights regarding the potential use of factors such as PTN in the clinical environment.

양극산화 처리된 타이타늄 표면에서 골형성 유전자 발현

김원석,김영석,전성배,전상호,이의석,장현석,권종진,임재석,Kim, Won-Seok,Kim, Young-Seok,Jeon, Seong-Bae,Jun, Sang-Ho,Lee, Eui-Suk,Jang, Hyon-Seok,Kwon, Jong-Jin,Rim, Jae-Suk 대한악안면성형재건외과학회 2012 Maxillofacial Plastic Reconstructive Surgery Vol.34 No.2

Purpose: The purpose of this study was to evaluate the expression of osteogenic genes associated with bone regeneration on anodizing titanium surface. Methods: $20{\times}20{\times}1$ (mm) commercially pure titanium plate was made, one group was pure titanium, second group was punched, and last group was punched and anodized by electrochemical method. Through the osteogenic cell culture model, the expression of extracellular matrix proteins, such as bone morphogenetic protein-2, bone sialoprotein, aggrecan, osteocalcin, Alkaline phosphatase, collagen I had been evaluated by Real-time polymerase chain reaction, and the morphology of growing cells was evaluated by scanning electron microscopy. Results: The attachment of mesenchymal stem cell was even and well-oriented on all Ti surfaces. The osteogene expression was increased on punching groups but, decreased on anodizing surfaces in 3 week samples. Conclusion: Punched anodizing Ti has possibility be using as a dental implant material, but further in vivo study would be needed.