In vitro zonation and toxicity in a hepatocyte bioreactor
In vitro zonation and toxicity in a hepatocyte bioreactor
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DOI：
10.1093/toxsci/kfi052
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发表时间：
2005-03-01
影响因子：
3.8
通讯作者：
Bhatia, SN
中科院分区：
文献类型：
--
作者：
Allen, JW;Khetani, SR;Bhatia, SN
肝脏的复杂结构与其对异生物质化合物的反应交织在一起。特别是，肝细胞亚群沿着血窦分布在1至3区，导致响应于毒性损伤的细胞死亡的原型“门脉周围”和“小叶中心”模式。因此，更接近代表这些亚专业化区域的体外模型可能对肝脏生理学和病理生理学的研究有价值。我们已经建立了一个灌注肝细胞生物反应器，对大鼠肝细胞和非实质细胞的共培养物施加生理氧梯度，从而产生一个体外模型的分区。为了预测和控制氧梯度，在平行板生物反应器中含有共培养物的氧传输首先进行数学建模和实验验证。暴露于这些生理氧梯度的共培养物证明了CYP2B和CYP3A蛋白的区域异质性，其模拟了在带状肝脏中观察到的分布。在生物反应器中的表达的分布被证明是不同的暴露于不同的化学诱导剂和生长因子，提供了一个潜在的平台，研究生理分区的反应。为了探索区域性肝毒性，生物反应器灌注APAP（对乙酰氨基酚）24小时，导致最大的细胞死亡在低氧出口区域类似于小叶中心坏死模式在体内观察到。这种肝细胞生物反应器系统能够进一步在体外研究涉及药物代谢和毒性的区域依赖性现象。
The complex architecture of the liver is intertwined with its response to xenobiotic compounds. In particular, hepatocyte subpopulations are distributed along the sinusoid in zones 1 to 3, leading to prototypical "periportal" and "centrilobular" patterns of cell death in response to a toxic insult. In vitro models that more closely represent these zones of sub-specialization may therefore be valuable for the investigation of hepatic physiology and pathophysiology. We have established a perfused hepatocyte bioreactor that imposes physiologic oxygen gradients on co-cultures of rat hepatocytes and non-parenchymal cells, thereby producing an in vitro model of zonation. In order to predict and control oxygen gradients, oxygen transport in a parallel-plate bioreactor containing co-cultures was first mathematically modeled and experimentally validated. Co-cultures exposed to these physiologic oxygen gradients demonstrated regionally heterogeneity of CYP2B and CYP3A protein that mimics the distribution seen in the zonated liver. The distribution of CYP expression in the bioreactor was shown to vary with exposure to different chemical inducers and growth factors, providing a potential platform to study physiologic zonal responses. In order to explore zonal hepatotoxicity, bioreactors were perfused with APAP (acetominophen) for 24 h, resulting in maximal cell death at the low-oxygen outlet region similar to centrilobular necrotic patterns observed in vivo. This hepatocyte bioreactor system enables further in vitro investigation into zonation-dependent phenomena involving drug metabolism and toxicity.