Biomicrofluidics. 2011 Jun;5(2):22207. doi: 10.1063/1.3580752. Epub 2011 Jun 29.
Embryonic stem cells (ESCs) are pluripotent with multilineage potential to differentiate into virtually all cell types in the organism and thus hold a great promise for cell therapy and regenerative medicine. In vitro differentiation of ESCs starts with a phase known as embryoid body (EB) formation. EB mimics the early stages of embryogenesis and plays an essential role in ESC differentiation in vitro. EB uniformity and size are critical parameters that directly influence the phenotype expression of ESCs. Various methods have been developed to form EBs, which involve natural aggregation of cells. However, challenges persist to form EBs with controlled size, shape, and uniformity in a reproducible manner. The current hanging-drop methods are labor intensive and time consuming. In this study, we report an approach to form controllable, uniform-sized EBs by integrating bioprinting technologies with the existing hanging-drop method. The approach presented here is simple, robust, and rapid. We present significantly enhanced EB size uniformity compared to the conventional manual hanging-drop method.
胚胎干细胞（ESCs）具有多能性和多谱系潜能，能够分化为机体中的几乎所有细胞类型，因此在细胞治疗和再生医学方面具有巨大的应用前景。ESCs 的体外分化始于一个被称为胚状体（EB）形成的阶段。EB 模拟了胚胎发生的早期阶段，在 ESC 的体外分化中起着至关重要的作用。EB 的均匀性和大小是直接影响 ESC 表型表达的关键参数。已经开发了各种方法来形成 EB，其中包括细胞的自然聚集。然而，仍然存在挑战，即如何以可重复的方式形成具有可控大小、形状和均匀性的 EB。目前的悬滴方法既费时又费力。在这项研究中，我们报告了一种通过将生物打印技术与现有的悬滴方法相结合来形成可控、均匀大小的 EB 的方法。与传统的手动悬滴方法相比，这里提出的方法简单、稳健且快速。我们提出的方法显著提高了 EB 大小的均匀性。
