Hernández-Tapia Laura G, Fohlerová Zdenka, Žídek Jan, Alvarez-Perez Marco A, Čelko Ladislav, Kaiser Jozef, Montufar Edgar B
CEITEC-Central European Institute of Technology, Brno University of Technology, Purkynova 123, 612 00 Brno, Czech Republic.
Tissue Bioengineering Laboratory, Faculty of Dentistry, Universidad Nacional Autónoma de México, Coyoacan, Mexico City 04510, Mexico.
Materials (Basel). 2020 Apr 22;13(8):1966. doi: 10.3390/ma13081966.
Biofabrication and maturation of bone constructs is a long-term task that requires a high degree of specialization. This specialization falls onto the hierarchy complexity of the bone tissue that limits the transfer of this technology to the clinic. This work studied the effects of the short-term cryopreservation on biofabricated osteoblast-containing structures, with the final aim to make them steadily available in biobanks. The biological responses studied include the osteoblast post-thawing metabolic activity and the recovery of the osteoblastic function of 3D-bioprinted osteoblastic structures and beta tricalcium phosphate (β-TCP) scaffolds infiltrated with osteoblasts encapsulated in a hydrogel. The obtained structures were cryopreserved at -80 °C for 7 days using dimethyl sulfoxide (DMSO) as cryoprotectant additive. After thawing the structures were cultured up to 14 days. The results revealed fundamental biological aspects for the successful cryopreservation of osteoblast constructs. In summary, immature osteoblasts take longer to recover than mature osteoblasts. The pre-cryopreservation culture period had an important effect on the metabolic activity and function maintain, faster recovering normal values when cryopreserved after longer-term culture (7 days). The use of β-TCP scaffolds further improved the osteoblast survival after cryopreservation, resulting in similar levels of alkaline phosphatase activity in comparison with the non-preserved structures. These results contribute to the understanding of the biology of cryopreserved osteoblast constructs, approaching biofabrication to the clinical practice.
骨构建体的生物制造和成熟是一项需要高度专业化的长期任务。这种专业化取决于骨组织的层次复杂性，这限制了该技术向临床的转化。这项工作研究了短期冷冻保存对生物制造的含成骨细胞结构的影响，最终目的是使其能够在生物样本库中稳定可用。所研究的生物学反应包括解冻后成骨细胞的代谢活性以及三维生物打印的成骨细胞结构和浸润有成骨细胞的β-磷酸三钙（β-TCP）支架在水凝胶中封装后的成骨细胞功能恢复。使用二甲基亚砜（DMSO）作为冷冻保护添加剂，将获得的结构在-80°C下冷冻保存7天。解冻后，将结构培养长达14天。结果揭示了成骨细胞构建体成功冷冻保存的基本生物学方面。总之，未成熟的成骨细胞比成熟的成骨细胞恢复所需时间更长。冷冻保存前的培养期对代谢活性和功能维持有重要影响，长期培养（7天）后冷冻保存时能更快恢复到正常水平。使用β-TCP支架进一步提高了冷冻保存后成骨细胞的存活率，与未保存的结构相比，碱性磷酸酶活性水平相似。这些结果有助于理解冷冻保存的成骨细胞构建体的生物学特性，使生物制造更接近临床实践。
