Optical selection of stem cells: application to human embryonic germ cells

人类胚胎生殖细胞(EGCs)能够转化为许多不同类型的细胞，包括那些具有治疗疾病潜力的细胞。出于这个原因，重要的是这些细胞广泛地提供给研究界。然而，获得健壮的纯系EGCs的难度已被证明是一个重大障碍。这方面的主要问题是用于制造EGCs的混合样本非常小，以及在实验室培养中繁殖精致的EGCs的困难。为了克服这些困难，我们需要一种方法来获得纯的EGCs及其前体。目前的方法是不合适的。微电子学为我们提供了能够对电信号进行快速、大规模并行处理的非常小规模的设备。同样，光电子学为我们提供了能够执行大规模并行处理光信号的小规模设备。近年来，为制造这些微小的微电子设备而开发的硅技术已被应用于操纵和控制非常少量的液体。这项技术的美妙之处在于它有可能成为一种集成的单微结构微芯片。在南安普敦，我们最近开发了光学芯片，用于在微米大小的电路中传输聚合物珠子。电路中的光携带这些珠子，并可以切换，以便它们可以向一个或另一个方向传输。这些珠子的速度取决于它们的成分和大小。我们建议以大致相同的方式运输细胞，因此不同的细胞将被光线沿着不同的轨道选择性地“推动”。光对于这一目的来说是理想的，特别是因为所使用的波长不会被细胞吸收，因此不会对细胞造成损害。不同的电池将通过它们沿轨道运输的速度来识别。因此，我们计划在不需要任何荧光分子标记的情况下鉴定EGCs-这是对这些细胞可以提纯的容易程度的重大改进。一旦我们有了用于实验的纯细胞群体，我们就可以发现在制造EGCs时哪些基因被开启和关闭，以及我们需要在实验室培养中添加哪些因素来保持EGCs的生长。这些进展将使我们能够将我们的细胞系存放在英国干细胞库中，以便其他研究人员可以访问它们，整个研究界可以在使用干细胞治疗人类疾病方面取得更快的进展。

Human embryonic germ cells (EGCs) are capable of turning into many different types of cell, including ones with the potential to treat disease. For this reason, it is important that these cells are widely available to the research community. However, the difficulty of acquiring robust pure lines of EGCs has proven a significant barrier. The major problems for this are an extremely small mixed starting sample from which EGCs are made and a difficulty of propagating the delicate EGCs in laboratory culture. To overcome these difficulties, we need to a method to acquire pure EGCs and their precurors. Current methods are unsuitable. Microelectronics has provided us with very small scale devices capable of performing rapid, massive parallel processing of electrical signals. Likewise, optoelectronics has provided us with small scale devices capable of performing massive parallel processing of optical signals. The silicon technology that has been developed to create these tiny microelectronic devices, has in recent years, been applied to the manipulation and control of very small quantities of fluids. The beauty of this technology is the potential for an integrated single microstructured microchip. In Southampton we have recently developed optical chips for the transport of polymer beads around micrometer sized circuits. Light in the circuits carries these beads and can be switched so that they can be transported in one direction or the other. The speed of these beads depends upon their composition and size. We propose to transport cells in much the same way, thus different cells will be selectively 'pushed' by the light along the different tracks. Light is ideal for this purpose, especially since the wavelength to be used is not absorbed by the cell and thus will not damage it. The different cells will be identified by how quickly they are transported along the tracks. So we plan to identify EGCs without the need for any labels of fluorescent molecules - a significant improvement in the ease with which these cells can be purified. Once we have a pure population of cells for our experiments, we can discover which genes are switched on and off as EGCs are made and what factors we need to add to our laboratory cultures to keep EGCs growing. These advances will allow us to deposit our cell lines in the UK Stem Cell Bank so that other researchers can access them and the research community as a whole can make faster progress towards using stem cells to treat human disease.