Regulating cell spatial distribution in gelatin hydrogel by bioactive nanoparticles

Abstract

Bioprinting, usually referring to that with cells, has received increasing attention for bone regeneration. However, keeping cells alive during printing processes, such as embedding, injection and curing, remains challenging, which has greatly restrained the available printing materials and techniques. To address this challenge, a material-regulating strategy was proposed, where the cell distribution can be regulated by materials themselves, rather than directly spatial control by printing. Therefore, cells do not need to be incorporated at the printing stage. The prerequisite for the success of this strategy is the feasibility to adjust cell proliferation, adhesion and migration by material cues. In this study, a hydrogel (BHP-gel) composed of bioactive hollow particles (BHP) and gelatin was developed and capable of doing that. Through formulating the BHP distribution in BHP-gels, cell distribution was simultaneously modulated in alignment with the BHP distribution, upon culturing cells on these hydrogels. This work provides an alternative approach for bioprinting, which might be extremely valuable when harsh printing conditions are inevitable.