Embryonic stem (ES) and induced pluripotent stem (iPS) cell colonies spontaneously differentiate and form three-dimensional multicellular aggregates, called embryoid bodies (EBs), when cultured in suspension without key stem cell growth factors. EB formation is a common intermediate during the in vitro differentiation of ES/iPS cells into specialized cell types. The size distribution of EBs plays a significant role in the efficiency of differentiation and in production yields (Dang et al. 2004; Ng et al. 2005; Falconnet et al. 2006).
Cultures maintained by enzymatic passage result in formation of heterogeneous EB population, varying in size and morphology, and in the ultimate yield of differentiated cells. Recent efforts to enrich EBs of preferred size to increase differentiation potential have included biocompatible coatings (Valamehr et al.
2008), microcontact printing (Bauwens et al. 2008), and forced aggregation systems (Burridge et al, 2007) with some success. The EB Generation Application on LEAP™ (Cyntellect, Inc.) was recently introduced (See Application Note: Automated Embryoid Body Generation powered by LEAP™ – Generation of EBs of
Specific Size), enabling the automated generation of EBs of specific sizes. These developments for improved EB generation have led to a need for routine quality assessment of EB number, size, and shape.