Acellular matrices derived from differentiating embryonic stem cells.

Embryonic stem cells (ESCs) can differentiate into all somatic cell types, thereby providing a robust cell source for regenerative medicine therapies. ESCs are commonly induced to differentiate via three-dimensional cell aggregates called embryoid bodies (EBs), which recapitulate cellular and molecular aspects of early tissue morphogenesis. Recent studies suggest that biomolecules synthesized by transplanted ESCs may provide instructive cues for tissue regeneration in vivo. Thus, the objective of this study was to acellularize EBs at different stages of differentiation in order to extract extracellular matrices containing ESC-derived biomolecules. Successive treatment with Triton X-100 and DNase significantly reduced the cellularity and completely inhibited the viability of EBs at various stages of differentiation. In addition, most DNA content (69-75%) was removed, while a portion of the original protein content (15-25%) was retained. Most importantly, extracellular matrix components produced by EBs were retained after acellularization. These results indicate that successful acellularization of EBs can be performed at various stages of differentiation to enable temporal modulation of acellular ECM composition. In addition, acellular matrices derived from EBs represent a novel route of obtaining molecular cues produced by ESCs actively undergoing morphogenesis, thus this technology may be relevant to the development of future regenerative medicine therapies.