Novel alternatives to conventional in-vitro-cancer models using 3D-bioprinting technology

Introduction 3D-bioprinting, an evolving biofabrication technique in regenerative medicine & tissue engineering with the prospect of mimicking the native tumour niche. The aim of this pilot study was to determine the optimal bioprinting parameters and to compare different nanocellulose (NC) based bioinks suitable to fabricate a 3D-bioprinted head and neck squamous cell carcinoma (HNSCC) model. Methods First, we designed a 3D-structure and optimized the respective bioprinting parameters. Further, we printed the designed 3D-structure with HNSCC cell lines (UM-SCC-11B & UM-SCC-22B) in different tunicate derived NC bioinks (Bioink1-TEMPO-mediated oxidised NC; Bioink2–Carboxymethylated NC). To determine the comparative bioink biocompatibility, we performed chemiluminescence based viability assay. Results Characterizing the bioconstructs for 16days in culture, we observed that UM-SCC-22B cell-laden bioconstructs (5*106 cells/mL bioink (NC in alginate at 2:1 ratio) bioprinted using 6-8kPa printing pressure at 2-3mm/s printing speed in R.T with 75-80% infill density) in bioink2 showed twice higher viability than cells in bioink1 bioconstructs. Moreover, the viability of UM-SCC-22B cells in NC bioink was significantly higher than UM-SCC-11B cells in the bioconstructs. Conclusion Differences in biocompatibility characteristics of NC bioink are likely caused by differences in bio-chemical & mechanical properties. The carboxymethyl backbone of bioink2 highly promotes cell proliferation & matrix modification whereas bioink1’s carboxyl backbone allows comparatively lower proliferation rate due to its heavy functional group & NC fiber distribution differences which additionally might affect viability. These findings are the first-steps towards the development of a 3D-bioprinted HNSCC model. Project funding by the state of Baden-Württemberg 3R-network (grant number 33-7533-6-1522/10/4) Publication History Article published online: 12 May 2023 Georg Thieme Verlag Rüdigerstraße 14, 70469 Stuttgart, Germany