Decoene Isaak, Svitina Hanna, Belal Hamed Mohamed, Economou Anastassios, Stegen Steve, Luyten Frank P, Papantoniou Ioannis
Skeletal Biology and Engineering Research Center, Department of Development and Regeneration, KU Leuven, O&N1, Herestraat 49, box 813, 3000, Leuven, Belgium.
Prometheus Translational Division of Skeletal Tissue Engineering, KU Leuven, O&N1, Herestraat 49, box 813, 3000, Leuven, Belgium.
Bone Res. 2025 Mar 26;13(1):41. doi: 10.1038/s41413-025-00418-z.
Clinical translation of tissue-engineered advanced therapeutic medicinal products is hindered by a lack of patient-dependent and independent in-process biological quality controls that are reflective of in vivo outcomes. Recent insights into the mechanism of native bone repair highlight a robust path dependence. Organoid-based bottom-up developmental engineering mimics this path-dependence to design personalized living implants scaffold-free, with in-build outcome predictability. Yet, adequate (noninvasive) quality metrics of engineered tissues are lacking. Moreover, insufficient insight into the role of donor variability and biological sex as influencing factors for the mechanism toward bone repair hinders the implementation of such protocols for personalized bone implants. Here, male and female bone-forming organoids were compared to non-bone-forming organoids regarding their extracellular matrix composition, transcriptome, and secreted proteome signatures to directly link in vivo outcomes to quality metrics. As a result, donor variability in bone-forming callus organoids pointed towards two distinct pathways to bone, through either a hypertrophic cartilage or a fibrocartilaginous template. The followed pathway was determined early, as a biological sex-dependent activation of distinct progenitor populations. Independent of donor or biological sex, a cartilage-to-bone transition was driven by a common panel of secreted factors that played a role in extracellular matrix remodeling, mineralization, and attraction of vasculature. Hence, the secreted proteome is a source of noninvasive biomarkers that report on biological potency and could be the missing link toward data-driven decision-making in organoid-based bone tissue engineering.
组织工程化先进治疗性医药产品的临床转化受到缺乏反映体内结果的患者依赖型和独立型过程中生物质量控制的阻碍。最近对天然骨修复机制的见解突出了一种强大的路径依赖性。基于类器官的自下而上的发育工程模仿这种路径依赖性，以设计无支架的个性化活体植入物，并具有内置的结果可预测性。然而，缺乏对工程组织的充分（非侵入性）质量指标。此外，对供体变异性和生物性别作为骨修复机制影响因素的作用缺乏足够的了解，阻碍了这种个性化骨植入方案的实施。在这里，将雄性和雌性骨形成类器官与非骨形成类器官在细胞外基质组成、转录组和分泌蛋白质组特征方面进行比较，以直接将体内结果与质量指标联系起来。结果，骨形成愈伤组织类器官中的供体变异性指向了两条不同的成骨途径，即通过肥大软骨或纤维软骨模板。所遵循的途径在早期就已确定，是不同祖细胞群体的生物性别依赖性激活。独立于供体或生物性别，软骨到骨的转变由一组共同的分泌因子驱动，这些因子在细胞外基质重塑、矿化和血管吸引中发挥作用。因此，分泌蛋白质组是无创生物标志物的来源，可报告生物活性，并且可能是基于类器官的骨组织工程中数据驱动决策的缺失环节。
