Engineering an in vitro living pump

在实验室中培养人体组织在寻找新的医学治疗方法和替代实验中的动物使用方面具有巨大的潜力。在这个项目中，我们的目标是在实验室内培养心脏组织，使其能够充当活泵。该项目是第一个利用人类胚胎干细胞制造功能性三维微型心脏的项目。干细胞可以根据需要增加数量，然后可以被说服形成心脏细胞（心肌细胞）。到目前为止，世界各地的科学家已经证明这是可能的，但我们想更进一步。在诺丁汉，我们已经可以用基因修饰技术制造出高纯度的心肌细胞群。现在，我们将把这些纯心肌细胞组装成利用细胞收缩的设备，并创建一个可以泵送液体的系统。为了实现这个雄心勃勃的目标，我们必须形成具有机械特性的聚合物柔性管，使心肌细胞能够收缩聚合物片。当心肌细胞松弛时，聚合物膜必须具有足够的弹性以恢复其原始表面积。我们将使用微米级的分子图案来创建一个化学痕迹，迫使心肌细胞组织成图案，最有效地利用它们在数千个细胞群体中的收缩。聚合物和细胞的薄片将被构造成带有单向阀的管子，并安装在一个生物反应器中，该生物反应器可以测量流体运动和微型心脏的收缩力。

Growing human tissues in the laboratory has great potential in the search for new medical treatments and in the replacement of animal use in experiments. In this project we aim to grow heart tissue that within the laboratory can act as a living pump. The project is the first to make a functional three-dimensional mini-heart using human embryonic stem cells. The stem cells can be increased in number on demand and then can be persuaded to form heart cells (cardiomyocytes). So far scientists around the World have shown this to be possible but we want to go a step further. At Nottingham we can already create highly pure cardiomyocyte populations using genetic modification techniques. Now we will assemble these pure cardiomyocytes into devices that harness the contraction of the cells and create a system that can pump liquid. To achieve this ambitious aim we must form flexible tubes of polymers that have mechanical properties that allow cardiomyocytes to contract sheets of the polymer. When the cardiomyocytes relax, the polymer film must be sufficiently elastic to recover its original surface area. We will use micron scale patterning of molecules to create a chemical trail that forces the cardiomyocytes to organise into patterns that make the most efficient use of their contraction within populations of thousands of cells. The sheets of polymers and cells will be constructed into tubes with one-way valves and installed in a bioreactor that can measure fluid movement and the force of the contraction of the mini-heart.