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bioRxiv · 10.1101/2022.02.28.482216

4D Cell-Condensate Bioprinting

Ding, A.·Tang, R.·He, F.·Lee, S. J.·Gasvoda, K.·Alsberg, E.
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Abstract

4D bioprinting techniques that facilitate formation of shape-changing scaffold-free cell condensates with prescribed geometries have yet been demonstrated. Here, a simple yet novel 4D bioprinting approach is presented that enables formation of a shape-morphing cell condensate-laden bilayer system comprised of an actuation layer and a cell condensate-supporting microgel (MG) layer. The strategy produces scaffold-free cell condensates which morph over time into predefined complex shapes. With a sequential printing (i.e., MG printing first onto the preformed actuation hydrogel layer and cell-only printing inside the pre-printed MG construct second), cell condensate-laden bilayers with specific geometries are readily fabricated and can be further UV-crosslinked to form strong interlayer adhesion. Since the bilayers have tunable deformability and MG degradation can be tailored, this enables controllable morphological transformations and on-demand liberation of cell condensates. With this system, large cell condensate-laden constructs with various complex shapes were obtained through predefined conformational conversions. As a proof-of-concept study, the formation of the letter "C" and helix-shaped robust cartilage-like tissues differentiated from human mesenchymal stem cells (hMSCs) was demonstrated. This new system brings about a new versatile 4D bioprinting platform idea that is anticipated to broaden and facilitate the applications of cell condensation-based 4D bioprinting.

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Ding, A., Tang, R., He, F., Lee, S. J., Gasvoda, K., Alsberg, E.. 2022-03-02. 4D Cell-Condensate Bioprinting. https://doi.org/10.1101/2022.02.28.482216

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