• Journal of Microbiology and Biotechnology
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• 제12권5호
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• pp.735-739
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• 2002

Large quantities of porcine hepatocyte aggregates with various degrees of aggregation (DA) could be obtained by controlling the suspension periods (0,9,24, and 48 h), and by entrapping the hepatocyte aggregates in model materials of encapsulation such as Ca-alginate and type-I collagen gels. The effects of DA on liver-specific functions of hepatocytes were evaluated in order to obtain optimum DA for the cell source of bioartificial liver (BAL) systems. Irregular rugged aggregates (size $75 \pm 28$ $\mu\textrm{m}$) farmed by 24 h of suspension culturing showed peak viability and hepatic functions such as ammonia removal and albumin secretion in the two types of entrapment systems, thus offering themselves as a stable cell source of a BAL system for hepatic functions and scale-up.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.67-67
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• 2005

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.389-389
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• 2005

• Journal of Animal Science and Technology
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• 제46권4호
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• pp.555-562
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• 2004

본 연구는 목저은 다음과 같다: 1) 돼지에서 150-kDa temary insulin-like growth faetor(IGF)complex의 한 구성 요소인 acid-labile subunit(ALS) 유전자 intron의 존재 확인. cloning 및 돼지 ALS(porcine ALS; pALS) complementary DNA(cDNA)의 3' 비해독(untranslated) 부위(3' UT) 증폭. cloning, 2) intron-spanning primer pair를 이용한 reverse transcription-polymerase chain reaction(RT-PCR) 방법에 의한 돼지 조직에서의 ALS 유전자 발현 분포 확인 및 3) 돼지 hepatocyte에서의 ALS 유전자 발현 여부 확인. 돼지 genomic DNA를 template로 하여 PCR 방법으로 예상된는 intron 부위를 증폭하고 plasmid vector에 삽입하여 염기서열을 결정한 결과 타 종의 ALS 유전자에서와 같은 위치에 1,371-base pair(bp)의 pALS intron이 존재함을 확인하였다. 역시 본 연구에서 간에서 추출한 RNA를 주형으로 시작하여 3' rapid amplification of cDNA end(3' RACE) 방법으로 147-bp의 3'UT를 합성하고 그 염기성열을 결정하였다. RT-PCR 결과 간은 물론 조사된 모든 돼지의 내장기관(신장, 폐, 비장)과 자성 생식기관(난소, 난관, 자궁) 및 골격근육에서 ALS 유전자가 발현됨이 밝혀졌다. 또한 돼지 간 조직에 대한 in-situ hybridization 결과 hepatocyte에서 ALS 유전자가 발현됨이 확인되었다. 이상의 결과는 ALS가 혈중 IGF의 저정/조절체로서의 주기능 외에 모세혈관 밖에서도 미지의 기능이 있을 기능성을 시사한다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.305-306
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• 2003

To treat fulminant hepatic failure (FHF) patients, various extracorporeal bioartificial liver (BAL) systems have been developed. Several requirements should be met for the development of BAL systems: hepatocytes should be cultured in a sufficiently high density; their metabolic functions should be of a sufficiently high level and duration; and the BAL systems module should permit scaling-up and aseptic handling. Several investigators have found that freshly isolated primary hepatocytes can be cultured into three dimensional, tightly packed, freely suspended, multicellular aggregates, or spheroids. These specialized cell structures exhibited enhanced liver specific functions and a prolonged differentiated state compared to cells maintained in a monolayer culture. Cells in spheroids appear to mimic the morphology and ultrastructure of the in vivo liver lobule. The ability of hepatocytes to organize into three-dimensional structures was hypothesized to contribute to their enhanced liver-specific activities. In this study, the ammonia removal rate and urea secretion rate of pig hepatocytes spheroids encapsulated in Ca-alginate bead were determined. A packed-bed bioreactor with encapsulated pig hepatocytes was devised as BAL support system. The efficacy of the system was evaluated in vitro.