Walther Anders Runge, Ditzel Nicholas, Kassem Moustapha, Andersen Morten Østergaard, Hedegaard Martin Aage Barsøe
SDU Biotechnology, Department of Green Technology, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
Endocrine Research (KMEB), Department of Endocrinology, Odense University Hospital and University of Southern Denmark, J.B. Winsløws Vej 25, DK-5000 Odense, Denmark.
Biomater Biosyst. 2022 Jul 28;7:100059. doi: 10.1016/j.bbiosy.2022.100059. eCollection 2022 Aug.
The development of novel biomaterials for regenerative therapy relies on the ability to assess tissue development, quality, and similarity with native tissue types in experiments. Non-invasive imaging modalities such as X-ray computed tomography offer high spatial resolution but limited biochemical information while histology and biochemical assays are destructive. Raman spectroscopy is a non-invasive, label-free and non-destructive technique widely applied for biochemical characterization. Here we demonstrate the use of fibre-optic Raman spectroscopy for quantitative monitoring of tissue development in subcutaneous calcium phosphate scaffolds in mice over 16 weeks. Raman spectroscopy was able to quantify the time dependency of different tissue components related to the presence, absence, and quantity of mesenchymal stem cells. Scaffolds seeded with stem cells produced 3-5 times higher amount of collagen-rich extracellular matrix after 16 weeks implantation compared to scaffolds without. These however, showed a 2.5 times higher amount of lipid-rich tissue compared to implants with stem cells. micro-computed tomography and histology showed stem cell mediated collagen and bone development. Histological measures of collagen correlated well with Raman derived quantifications (correlation coefficient 0.74, 0.93). In the absence of stem cells, the scaffolds were largely occupied by adipocytes. The technique developed here could potentially be adapted for a range of small animal experiments for assessing tissue engineering strategies at the biochemical level.
用于再生治疗的新型生物材料的开发依赖于在实验中评估组织发育、质量以及与天然组织类型相似性的能力。诸如X射线计算机断层扫描等非侵入性成像方式提供了高空间分辨率，但生化信息有限，而组织学和生化分析具有破坏性。拉曼光谱是一种广泛应用于生化表征的非侵入性、无标记且非破坏性技术。在此，我们展示了使用光纤拉曼光谱对小鼠皮下磷酸钙支架中16周内的组织发育进行定量监测。拉曼光谱能够量化与间充质干细胞的存在、缺失和数量相关的不同组织成分的时间依赖性。与未接种干细胞的支架相比，接种干细胞的支架在植入16周后产生的富含胶原蛋白的细胞外基质量高出3至5倍。然而，与植入干细胞的支架相比，这些支架显示出富含脂质的组织量高出2.5倍。微型计算机断层扫描和组织学显示了干细胞介导的胶原蛋白和骨骼发育。胶原蛋白的组织学测量结果与拉曼光谱得出的定量结果相关性良好（相关系数分别为0.74和0.93）。在没有干细胞的情况下，支架主要被脂肪细胞占据。这里开发的技术有可能适用于一系列小动物实验，以便在生化水平评估组织工程策略。
