Extrusion-based 3D printing of photo-crosslinkable gelatin and κ-carrageenan hydrogel blends for adipose tissue regeneration.

Current soft tissue repair techniques for women with breast cancer remain associated with several drawbacks including surgical complications and a high resorption rate for lipofilling techniques. Hence, the need to develop improved adipose tissue reconstruction strategies. Additive manufacturing can be a promising tool towards the development of patient-specific scaffolds which are able to support adipose tissue engineering. In the present work, scaffolds composed of both methacrylamide-modified gelatin (Gel-MA) and methacrylated κ-carrageenan (Car-MA), i.e. hydrogel blends, were developed using extrusion-based 3D printing in order to establish a close resemblance to the native extracellular matrix. The hydrogel blends were benchmarked to scaffolds constituting of only Gel-MA. Our results indicate that both types of scaffolds remain stable over time (21 days), are able to absorb large amounts of water and exhibit mechanical properties comparable to those of native breast tissue (2 kPa). Furthermore, a similar cell viability (> 90%) and proliferation rate after 14 days was obtained for adipose tissue-derived stem cells (ASCs) upon seeding onto both types of scaffolds. Additionally, the ASCs were able to differentiate into the adipogenic lineage on the hydrogel blend scaffolds, although their differentiation potential was lower compared to that of ASCs seeded onto the Gel-MA scaffolds.