Carrier-assisted cell transplantation offers new strategies to improve the clinical outcomes of cellular therapies. Bacterial nanocellulose (BC) is an emerging biopolymer that might be of great value in the development of animal-free, customizable, and temperature-stable novel cell carriers. Moreover, BC exhibits a myriad of modification possibilities to incorporate additional functionalities. Here, we have synthesized BC-titanium dioxide (TiO₂) nanocomposites (BC/TiO₂) to evaluate and compare the suitability of not only BC but also a model hybrid nanobiomaterial as cell transplantation supports. This work provides thorough information on the interactions between BC-based substrates and model human cells in terms of cell attachment, morphology, proliferation rate, and metabolic activity. Two methods to partially retrieve the adhered cells are also reported. Both BC and BC/TiO₂ substrates are positively evaluated in terms of cytocompatibility and endotoxin content without detecting major differences between BC and BC nanocomposites. Lastly, the effective cryopreservation of cells-BC and cells-BC/TiO₂ constructs, yielding high cell viability and intact cell carrier's characteristics after thawing, is demonstrated. Taken together, our results show that both BC and BC/TiO₂ enable to integrate the processes of expansion and long-term storage of human cells in transportable, robust and easy to manipulate supports.

中文翻译：

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细菌纳米纤维素和二氧化钛杂化物：细胞相容性和低温保存细胞载体

载体辅助细胞移植为改善细胞疗法的临床疗效提供了新的策略。细菌纳米纤维素（BC）是一种新兴的生物聚合物，在开发无动物，可定制且温度稳定的新型细胞载体方面可能具有重要价值。而且，BC展示了无数的修改可能性以合并其他功能。在这里，我们合成了BC-二氧化钛（TiO ₂）纳米复合材料（BC / TiO ₂），以评估和比较不仅适用于BC，而且适用于作为细胞移植支持物的模型杂交纳米生物材料的适用性。这项工作就细胞附着，形态，增殖速率和代谢活性而言，提供了有关基于BC的底物与模型人细胞之间相互作用的详尽信息。还报道了两种部分回收粘附细胞的方法。BC和BC / TiO ₂底物都在细胞相容性和内毒素含量方面得到了积极评估，而没有发现BC和BC纳米复合材料之间的主要差异。最后，有效冷冻保存细胞-BC和细胞-BC / TiO ₂展示了在融化后可产生高细胞活力和完整细胞载体特性的构建体。两者合计，我们的结果表明BC和BC / TiO _2都能够将人类细胞的扩增和长期储存过程整合到可运输，坚固且易于操纵的载体中。