Developing Trabecular and Cortical Bone Microstructure ThruDecellularized Extracellular Matrix Composite Hydrogels

Objective: There have been many efforts to develop bone-likeconstruct to mimic the trabecular and cortical bone microstructureprecisely. Novel bone tissue engineering approacheshave offered decellularized bone extracellular matrix (dECM)as a promising biomaterial that holds the biochemical and biophysicalcues of native bone. The composite hydrogel containsdECM and other bone imitative biomaterials would provide theother cues. Therefore, we reasoned that calcium phosphate cement(CPC) and silk fibroin-derived peptide (SFp) could formthe composite hydrogel with dECM to imitate the trabecular/cortical bone microstructure.Materials and Methods: To this end, the solubilized dECMcombined with ۱.۵ % (V/V) CPC and ۱۵۰ μg/ml SFp have beenprepared separately and seeded with adipose derived mesenchymalstem cells. Then, the morphological and geometricalanalysis of CPC/dECM and SFp/dECM constructs were performedusing scanning electron microscopy energy dispersivespectrometry (SEM-EDS). Also, the mechanical strength analysisof resulted constructs was performed.Results: Interestingly, the MSCs have secreted the sufficientextracellular matrix thru both CPC/dECM and SFp/dECM.The SEM-EDS analysis manifested that CPC/dECM hydrogelimitated the trabecular-like structure and SFp/dECM hydrogelmimicked the cortical-like structure. Furthermore, the mechanicalproperty analysis of CPC/dECM hydrogel compared to SFp/dECM manifest a higher compression strength.Conclusion: Altogether, this study demonstrates that the bonelikeconstruct which imitates the bone microstructure specificallycan be designed in detail.

Keywords:

Bone tissue engineering , silk peptide , dECM , CPC , bone microstructure