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bioRxiv · 10.1101/2020.05.31.122309

Aspiration-assisted Freeform Bioprinting of Tissue Spheroids in a Yield-stress Gel

Ayan, B.·Zhang, Z.·Celik, N.·Zhou, K.·Wu, Y.·Costanzo, F.·Ozbolat, I. T.
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Abstract

Bioprinting of cellular aggregates, such as tissue spheroids or organoids, in complex three-dimensional (3D) arrangements has been a major obstacle for scaffold-free fabrication of tissues and organs. In this research, we unveiled a new approach to the bioprinting of tissue spheroids in a yield stress granular gel, which exhibited unprecedented capabilities in freeform positioning of spheroids in 3D. Due to its Herschel-Bulkley and self-healing properties as well as its biological inertness, the granular gel supported both the positioning and self-assembly of tissue spheroids. We studied the underlying physical mechanism of the approach to elucidate the interactions between the aspirated spheroids and the gels yield-stress during the transfer of spheroids from cell media to the gel. We demonstrate the application of the proposed approach in the realization of various freeform shapes and self-assembly of human mesenchymal stem cell spheroids for the construction of cartilage and bone tissues.

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Ayan, B., Zhang, Z., Celik, N., Zhou, K., Wu, Y., Costanzo, F., Ozbolat, I. T.. 2020-06-01. Aspiration-assisted Freeform Bioprinting of Tissue Spheroids in a Yield-stress Gel. https://doi.org/10.1101/2020.05.31.122309

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