• Quantification of early adipose-derived stem cell survival: comparison between sodium iodide symporter and enhanced green fluorescence protein imaging.

    요약 : 
    Objective: Strategies to overcome the problem of extensive early stem cell loss following transplantation requires a method to quantitatively assess their efficacy. This study compared the ability of sodium/iodide symporter (NIS) and enhanced green fluorescent protein (EGFP) imaging to monitor the effectiveness of treatments to enhance early stem cell survival.
    Methods: Human adipose-derived stem cells (ADSCs) transduced with an adenoviral vector to express both NIS and EGFP were mixed with culture media (control), matrigel (matrigel group) or pro-survival cocktail
    (PSC group), and 5×106 cells were injected into thigh muscles of C57BL/6 mice. Animals underwent serial optical imaging and 99mTcO4 – scintigraphy. Image-based EGFP fluorescence and 99mTcO4 – uptake was measured by region-of-interest analysis, and extracted tissues were measured for 99mTc activity. Fluorescent intensity measured from homogenized muscle tissue was used as reference for actual amount of viable ADSCs.
    Results: ADSCs were efficiently transduced to express EGFP and NIS without affecting proliferative capacity. The absence of significant apoptosis was confirmed by annexin V FACS analysis and Western blots for activated caspase-3. Both fluorescence optical imaging and 99mTcO4 – scintigraphy visualized implanted cells in living mice for up to 5days. However, optical imaging displayed large variations in fluorescence intensity, and thus failed to detect difference in cell survival between groups or its change over time. In comparison, 99mTcO4 -scintigraphy provided more reliable assessment of within-in group donor cell content as well as its temporal change. As a result, NIS imaging was able to discern beneficial effects of matrigel and pro-survival cocktail treatment on early ADSC survival, and provided quantitative measurements that correlated to actual donor cell content within implanted tissue.
    Conclusion: NIS reporter imaging may be useful for noninvasively assessing the efficacies of strategies designed to improve early survival of transplanted stem cell

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  • New Isolation Technique and Culture System for Clinical Applications of Human Amniotic Epithelial Stem Cells.

    요약 : 
    태반은 성체줄기세포의 보고이다. 특히 양막상피세포는 배아줄기세포의 줄기세포 능력을 나타내는 세포 표면표시자들을 그대로 발현하는 줄기세포로 알려져 있다. 하지만 상피세포를 실험실에서 지지세포 없이 대량 증식 배양하는 것은 상피세포가 가지고 있는 내인성 성격으로 인해 어렵다. 본 연구에서는 디티오트레이톨(Dithiothreitol; DTT)과 ROCK 저해제(Rho-associated kinase inhibitor)를 이용하여 양막상피세포를 분리하고 배양하는데 있어서 임상적용이 가능한 수준의 세포를 얻었고, 최적의 세포상태를 유지하였다. 본 연구에서 분리배양된 양막상피세포는 상피세포의 특성과 줄기세포의 특성을 발현하였다. 결론적으로 줄기세포 치료를 이용한 재생의학의 관점에서 인간태반 유래 양막상피줄기세포는 아무런 윤리적인 논란을 일으키지 않는 주요한 줄기세포 치료제의 재료로서 여러 가지 질병 치료에 사용될 수 있을 것이다.

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  • Isolation and characterization of mesenchymal stem cells from human amnion and decidua.

    요약 : 
    Objectives: The purpose of this study is to isolate a population of multipotent cells from human amnion and decidua, respectively.
    Methods: Human placentas (gestational age, 30~42 weeks) were obtained after vaginal or cesarean deliveries. Amnions and deciduas were divided mechanically. The collected cells from the amnion and decidua were cultured. Cultured cells were immunophenotypically characterized. The adipogenic, osteogenic and neurogenic differentiation capacities were tested, and their growth kinetics were analyzed.

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  • In vitro migration capacity of human adipose tissue-derived mesenchymal stem cells reflects their expression of receptors for chemokines and growth factors.

    요약 : 
    The homing properties of adipose tissue-derived mesenchymal stem cells (AdMSCs) have stimulated intravenous applications for their use in stem cell therapy. However, the soluble factors and corresponding cellular
    receptors responsible for inducing chemotaxis of AdMSCs have not yet been reported. In the present study, the migration capacity of human AdMSCs (hAdMSCs) toward various cytokines or growth factors (GFs) and the expression of their receptors were determined. In a conventional migration assay, PDGF-AB, TGF-β1, and TNF-α showed the most effective chemoattractant activity. When AdMSCs were preincubated with various chemokines or GF, and then allowed to migrate toward medium containing 10% FBS, those preincubated with TNF-α showed the highest migratory activity. Next, hAdMSCs were either preincubated or not with TNF-α, and allowed to migrate in response to various GFs or chemokines. Prestimulation with TNF-α increased the migration activity of hAdMSCs compared to unstimulated hAdMSCs. When analyzed by FACS and RT-PCR methods, hAdMSCs were found to express C-C chemokine receptor type 1(CCR1), CCR7, C-X-C chemokine receptor type 4 (CXCR4), CXCR5, CXCR6, EGF receptor, fibroblast growth factor receptor 1, TGF-β receptor 2, TNF receptor superfamily member 1A, PDGF receptor A and PDGF receptor B at both the protein and the mRNA levels. These results indicate that the migration capacity of hAdMSCs is controlled by various GFs and chemokines. Prior in vitro modulation of the homing capacity of hAdMSCs could stimulate their movement into injured sites in vivo when administered intravenously, thereby improving their therapeutic potential.

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