세포외 기질(External Cellular Metrics, ECM)에 따른 Endothelial Cell(EC)의 체외배양능 분석

임맑음,김영지,황성수,오건봉,신유리안나,김영임,이주영,옥선아 한국동물생명공학회(구 한국동물번식학회) 2016 발생공학 국제심포지엄 및 학술대회 Vol.2016 No.10

Rat Primary Hepatocyte의 2차원 배양과 3차원 배양에 따른 생리 활성능과 대사능에 관한 연구

임맑음,김영지,신유리안나,오건봉,황성수,김영임,허태영,옥선아 한국수정란이식학회 2016 한국동물생명공학회지 Vol.31 No.3

There is a growing interest in the application of primary hepatocytes for treatment of liver diseases in humans and for drug development. Several studies have focused on long-term survival and di-differentiation blocking of primary hepatocytes in an in vitro culture system. Therefore, the present study also aimed to optimize an in vitro culture system using primary rat hepatocytes. Primary rat hepatocytes from 6-week-old male Crl:CD rats were isolated using a modified two-step collagenase perfusion. Healthy 3.5 × 106 primary rat hepatocytes were seeded into a 2 dimensional (2D) culture in a 25T culture flask coated with collagen type I or into a 3D culture in a 125-ml spinner flask for 7 days. Production of plasma protein (ALB and TF), apoptosis (BAX and BCL2), and CYP (CYP3A1) related genes were compared between the 2D and 3D culture systems. The 3D culture system had an advantage over the 2D system because of the relatively high expression of ALB and low expression of BAX in the 3D system. However, the level of CYP3A1 did not improve in the 3D culture with and without the presence of a dexamethasone inducer. Therefore, 3D culture has an advantage for albumin production and primary rat hepatocyte survivability, but a low expression of CYP3A1 indicated that primary rat hepatocytes require a high–density culture for stress reduction by continuous flow.

세포외 기질(External Cellular Metrics, ECM)에 따른 Endothelial Cell(EC)의 체외배양능 분석

임맑음,김영지,황성수,오건봉,신유리안나,김영임,이주영,옥선아 한국수정란이식학회 2016 한국수정란이식학회 학술대회 Vol.2016 No.10

최근 조직공학 기술의 발달로 재해와 질병으로 인한 손상된 조직과 장기의 대체연구들 이 진행되고 있다. 장기 대체 연구의 핵심 요소 중 하나는 재건된 조직이나 장기가 혈관 망을 형성하여 host tissue로부터 양분과 산소의 전달이다. 본 연구는 조직공학 기법을 이용하여 장기 재건에 필수적인 혈관 재건을 위해 혈관을 구성하는 주세포인 endothelial cell을 체외에서 배양하는 것이다. Endothelial cell(EC)배양을 위해서는 세포지지체인 세 포외 기질(External cellular metrics, ECM)을 필요로 하기 때문에 ECM중에 대표적인 collagen과 gelatin을 사용하여 지지체에 따른 체외배양능을 비교하였다. 실험 동물로는 돼지 대동맥을 채취하여, 대동맥 속에 collagenase type I을 주입하고, 혈관의 입·출구를 봉합한 상태로 10분 간 37℃에서 처리하였다. 관류된 용액은 10% FBS가 함유된 기본배 양액(EGM-2 media)을 사용하여 2번 수세한 후 회수된 세포를 각각의 ECM이 처리된 dish위에서 배양 하였다. EC세포인지를 확인하기 위해서 EC표지 인자인 CD31과 vWF 항체의 발현을 flow cytometry로 확인 하였고, 회수된 세포에서 두 단백질이 모두 발현 되었다. ECM에 따른 EC의 세포 형태를 비교하였을 때 형태학적 차이는 없었다. Basement Membrane Extract위에서 calcein-AM으로 염색된 EC는 ECM의 종류와 상관 없이 2-6시간 사이에 Tube Formation을 보였다. 또한 endothelial cell의 표지 마크인 CD31, Flk1, vWF의 mRNA 발현양과 IHC에 의한 단백질 발현을 조사한 결과 collagen 지지체 위에서 배양된 endothelial cells에서 발현양이 더 높았다. 결론적으로 두 가지 ECM에서 모두 성공적으로 endothelial cell의 배양이 가능하지만 collagen위에서 배양된 endothelial cell이 더 우수한 maintenance능력을 가짐을 확인 할 수 있었다.

이종 장기이식 및 조직 공학을 위한 Alpha gal 유전자 결손돼지 (1, 3-galactosyltransferase-deficient pigs)에서 혈관내피세포(aortic endothelial cells)의 구축

옥선아,임맑음,김영지,ImranUllah,신유리안나,김영임,오건봉,황성수,허태영,이승훈,임기순 한국수정란이식학회 2017 한국동물생명공학회지 Vol.32 No.3

Tissue engineering (TE) has been developed to create functional organs and tissue by combining 3D matrix and cells in vitro. Vascularization and angiogenesis are utmost important for supply of nutrients and oxygen in tissue engineered organs. The present study was performed to isolate and characterize primary endothelial cells (EC) from aorta of alpha 1, 3-enzyme galactosyltransferase knock out (GalT KO) pig, to minimize immune rejection and analyze body immune system for future xenotransplantation studies. Isolation of primary EC from aorta were performed by incubation with dispase for 8-10 min at 37°C. Primary EC were cultured in EC growth medium on different extra cellular matrix (ECM), either collagen or gelation. Primary EC exhibits morphological characteristics and showed positive expressions of EC specific marker proteins i.e. PECAM1, KDR and VWF despite of their ECM surface; however, on collagen based surface they showed increase in mRNA level analyzed by qPCR. Primary EC cultured on collagen were sorted by flow cytometer using KDR marker and cultured as KDR positive cells and KDR negative cells, respectively. KDR positive cells showed dramatically increased in PECAM1 and VWF level as compared to KDR negative cells. Based on the above results, primary EC derived from GalT KO are successfully isolated and survived continuously in culture without becoming overgrown by fibroblast. Therefore, they can be utilize for xeno organ transfer, tissue engineering, and immune rejection study in future.

Effect of gangliosides on LPS stimulation and nitric oxide release in porcine kidney cell line PK15

이주택,고기성,임맑음,Ghislain Moussavou,김지수,장규태,추영국 한국통합생물학회 2013 Animal cells and systems Vol.17 No.5

Gangliosides, which are glycosphingolipids containing sialic acid, play important regulatory roles in cell proliferation and adhesion, survival and immunosuppressive activity. In this study, we investigated whether gangliosides can affect cell viability in the porcine kidney (PK) cell line, PK15, when stimulated with lipopolysaccharide (LPS). As the amount of LPS that PK15 cells were treated with was increased, the cell proliferation decreased, whereas nitric oxide (NO) production increased. High-performance thin-layer chromatography (HPTLC) and immunofluorescence analyses showed that GM3 and GM2 ganglioside expression significantly decreased in LPS-stimulated PK15 compared to unstimulated PK15. UDP-glucose ceramide glucosyltransferase (Ugcg), which catalyzes the initial step in the glycosphingolipid biosynthesis pathway, was knocked-down in PK15 by using short hairpin RNA (shRNA). Western blot and HPTLC analyses showed that the Ugcg protein expression decreased and the ganglioside expression decreased in the Ugcg-knockdown (UKD) PK15. There was a greater decrease in cell proliferation in LPS-stimulated UKD PK15 cells than in LPS-stimulated PK15 cells without the UKD. However, the increase in NO release was greater in LPS-stimulated UKD PK15 cells than in LPS-stimulated PK15 cells without the UKD. These findings suggest that gangliosides may interact with components of the inflammatory response pathway and, thus, are relevant for the design of future therapeutic strategies intended to prolong xenotransplantation.

In vitro 3-D culture demonstrates incompetence in improving maintenance ability of primary hepatocytes

Imran Ullah,옥선아,김영지,임맑음,오건봉,황성수,Yurianna Shin,김영임,임기선,허태영 한국통합생물학회 2017 Animal cells and systems Vol.21 No.5

Primary hepatocytes (PHs) are considered the ‘gold standard’ in drug screening owing to their ability to express many drug-metabolizing enzymes and transporters. Culturing hepatocytes and maintaining their fate in vitro is a major issue since last decade. The main problem with in vitro hepatocytes culture is that they rapidly lose their hepatic morphology and liver-specific functions in culture. Herein, we isolated rat PHs, and cultured them in monolayers (2-D) and spheroids (3-D). The 2-D-cultured PHs exhibited elongated morphology, whereas the 3-Dcultured PHs exhibited spheroid morphology with gradual diameter decrease until 7 days. After 7 days of in vitro culture, PHs were analyzed for the expression of hepatic (Alb, Tf, and Afp) and apoptotic markers (Bax and Bcl2), and co-expression of CYP3A1 and Abumin after 2 and 7 days. Furthermore, in both cultures, PHs were induced with 3-methylcholanthrene (3-MC, Cyp1a-specific inducer) and dexamethasone (Cyp3a-specific inducer) for 48 and 72 h, respectively. The mRNA levels of Cyp1a and Cyp3a were analyzed in induced (3-MC, dexamethasone) and non-induced PHs. After 7 days of in vitro culture, PHs exhibited dramatic downregulation of hepatic marker expression in both cultures. Furthermore, apoptotic marker expression was higher in the 2-D-cultured PHs than 3-D-cultured PHs. The mRNA levels of Cyp1a and Cyp3a indicated higher RNA content in the 2-D-cultured PHs after 48 h of induction. Therefore, we concluded that there was no significant difference between the culture systems, and further studies are required to identify the essential components for in vitro PH culture rather than culture systems.