Human bone tissue-derived ECM hydrogels: Controlling physicochemical, biochemical, and biological properties through processing parameters

Decellularized tissues offer significant potential as biological materials for tissue regeneration due to their ability to preserve the complex compositions and architecture of the native extracellular matrix (ECM). While the use of decellularized ECM hydrogels from bovine and porcine bone tissues has been extensively studied, the evaluation and derivation of decellularized matrices from human bone tissue remain largely unexplored. The objective of this study was to investigate how the physiochemical and biological properties of ECM hydrogels derived from human bone ECM could be controlled by manipulating bone powder size (45-250 m, 250-1000 m, and 1000-2000 m) and ECM composition through modulation of digestion time (3, 5, and 7 days). The current studies demonstrate that a reduction in material bone powder size and an increase in ECM digestion time resulted in enhanced protein concentrations in the ECM hydrogels, accompanied by the presence of a diverse array of proteins. Furthermore, these adjustments in the physicochemical properties generated improved gelation strength of the hydrogels. The evaluation of human bone marrow-derived stromal cells (HBMSCs) cultured on ECM hydrogels derived from 45-250 m bone powder, treated for 7 days, demonstrated enhanced osteogenic differentiation compared to hydrogels derived from both larger bone powders and collagen gels. In conclusion, this study highlights the significant promise of human bone ECM hydrogels as biologically active materials for bone regeneration. The ability to manipulate digestion time and bone powder size enables the generation of hydrogels with enhanced release of ECM proteins and appropriate gelation and rheological properties, offering new opportunities for application in bone tissue engineering.