Lopez-Muñoz Gerardo A, Ortega Maria Alejandra, Ferret-Miñana Ainhoa, De Chiara Francesco, Ramón-Azcón Javier
Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri I Reixac, 10-12, 08028 Barcelona, Spain.
ICREA-Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain.
Nanomaterials (Basel). 2020 Dec 15;10(12):2520. doi: 10.3390/nano10122520.
Non-alcoholic fatty liver (NAFLD) is a metabolic disorder related to a chronic lipid accumulation within the hepatocytes. This disease is the most common liver disorder worldwide, and it is estimated that it is present in up to 25% of the world's population. However, the real prevalence of this disease and the associated disorders is unknown mainly because reliable and applicable diagnostic tools are lacking. It is known that the level of albumin, a pleiotropic protein synthesized by hepatocytes, is correlated with the correct function of the liver. The development of a complementary tool that allows direct, sensitive, and label-free monitoring of albumin secretion in hepatocyte cell culture can provide insight into NAFLD's mechanism and drug action. With this aim, we have developed a simple integrated plasmonic biosensor based on gold nanogratings from periodic nanostructures present in commercial Blu-ray optical discs. This sensor allows the direct and label-free monitoring of albumin in a 2D fatty liver disease model under flow conditions using a highly-specific polyclonal antibody. This technology avoids both the amplification and blocking steps showing a limit of detection within pM range (≈0.26 ng/mL). Thanks to this technology, we identified the optimal fetal bovine serum (FBS) concentration to maximize the cells' lipid accumulation. Moreover, we discovered that the hepatocytes increased the amount of albumin secreted on the third day from the lipids challenge. These data demonstrate the ability of hepatocytes to respond to the lipid stimulation releasing more albumin. Further investigation is needed to unveil the biological significance of that cell behavior.
非酒精性脂肪性肝病（NAFLD）是一种与肝细胞内慢性脂质蓄积相关的代谢紊乱疾病。这种疾病是全球最常见的肝脏疾病，据估计，全球高达25%的人口患有该疾病。然而，这种疾病及相关病症的实际患病率尚不清楚，主要原因是缺乏可靠且适用的诊断工具。众所周知，白蛋白是肝细胞合成的一种多效性蛋白质，其水平与肝脏的正常功能相关。开发一种能够直接、灵敏且无标记地监测肝细胞培养中白蛋白分泌的补充工具，可以深入了解NAFLD的发病机制和药物作用。为此，我们基于商用蓝光光盘中存在的周期性纳米结构开发了一种简单的集成等离子体生物传感器。该传感器使用高度特异性的多克隆抗体，能够在流动条件下对二维脂肪肝疾病模型中的白蛋白进行直接且无标记的监测。这项技术避免了扩增和封闭步骤，检测限在皮摩尔范围内（约0.26 ng/mL）。借助这项技术，我们确定了使细胞脂质蓄积最大化的最佳胎牛血清（FBS）浓度。此外，我们发现肝细胞在脂质刺激后的第三天增加了白蛋白的分泌量。这些数据证明了肝细胞对脂质刺激做出反应并释放更多白蛋白的能力。需要进一步研究来揭示这种细胞行为的生物学意义。
