Bone-Derived dECM Hydrogels Support Tunable Microenvironments for In Vitro Osteogenic Differentiation.

Decellularized extracellular matrix (dECM)-based biomaterials mimic native ECM and support 3D cell culture. A photocrosslinkable porcine bone-derived dECM hydrogel (dECM-MA) is developed with tunable mechanical properties for tissue-specific in vitro models. Trabecular bone is demineralized with 10% EDTA and decellularized via osmotic shock using 3.4 m NaCl, reducing DNA content by 94% while preserving key ECM proteins. Proteomic analysis identifies 81 matrisome proteins, with 76 shared between native and decellularized tissue. The dECM is solubilized by pepsin digestion and functionalized with methacryloyl groups, achieving 87-98% functionalization. Photocrosslinked dECM-MA hydrogels shows tunable Young's moduli (0.5-120 kPa) depending on polymer concentration (0.25-2% w/v) and crosslinking duration (8-120 s). Primary human osteoblasts (hOBs) encapsulated in dECM-MA (5, 10, and 20 kPa) remains viable and exhibits osteogenic morphology. In 10 kPa hydrogels, hOBs shows increased metabolic activity, elevated alkaline phosphatase, and mineral deposition (µCT, Alizarin Red). Expression of DMP-1 and osteocalcin indicates cell maturation and ECM remodeling. This study demonstrates the feasibility of creating tunable, bone-specific dECM hydrogels for 3D culture. dECM-MA provides a controllable matrix environment and represents a versatile platform for disease modeling and drug screening in tissue-specific microenvironments.