Centre for Translational Bone, Joint- and Soft Tissue Research, Medical Faculty and University Hospital, Technische Universität Dresden, D-01307 Dresden, Germany.
Int J Mol Sci. 2021 Jul 7;22(14):7316. doi: 10.3390/ijms22147316.
In vitro evaluation of bone graft materials is generally performed by analyzing the interaction with osteoblasts or osteoblast precursors. In vitro bone models comprising different cell species can give specific first information on the performance of those materials. In the present study, a 3D co-culture model was established comprising primary human osteoblasts, osteoclasts and osteocytes. Osteocytes were differentiated from osteoblasts embedded in collagen gels and were cultivated with osteoblast and osteoclasts seeded in patterns on a porous membrane. This experimental setup allowed paracrine signaling as well as separation of the different cell types for final analysis. After 7 days of co-culture, the three cell species showed their typical morphology and gene expression of typical markers like and . Furthermore, relevant enzyme activities for osteoblasts (ALP) and osteoclasts (TRAP, CTSK, CAII) were detected. Osteoclasts in triple culture showed downregulated TRAP () and expression and decreased TRAP activity. and expression of osteoblasts in triple culture were upregulated. The expression of the osteocyte marker E11 () was unchanged; however, osteocalcin () expression was considerably downregulated both in osteoblasts and osteocytes in triple cultures compared to the respective single cultures.
体外评估骨移植物材料通常通过分析与成骨细胞或成骨细胞前体的相互作用来进行。包含不同细胞物种的体外骨模型可以提供有关这些材料性能的特定初步信息。在本研究中，建立了一个包含原代人成骨细胞、破骨细胞和成骨细胞的 3D 共培养模型。成骨细胞是从嵌入胶原凝胶中的成骨细胞分化而来，并与接种在多孔膜上的成骨细胞和破骨细胞进行培养。这种实验设置允许旁分泌信号传递以及不同细胞类型的分离，以进行最终分析。共培养 7 天后，三种细胞类型表现出其典型的形态和典型标志物的基因表达，如 和 。此外，还检测了相关的成骨细胞（ALP）和破骨细胞（TRAP、CTSK、CAII）的酶活性。在三重培养中的破骨细胞表现出下调的 TRAP（）和 表达和降低的 TRAP 活性。三重培养中的成骨细胞的 和 表达上调。成骨细胞标志物 E11（）的表达保持不变；然而，与各自的单一培养相比，三重培养中的成骨细胞和成骨细胞中的骨钙素（）表达显著下调。
