Engineering a platform combining decellularized ECM and native bone surface topography for investigating osteoblastic function

Utilization of cell derived decellularized extracellular matrices (dECM) is a highly versatile way to introduce complex cell specific native-like microenvironment in vitro. While dECMs have been used in various applications, surface functionalization of biomaterials with cell-derived dECMs that maintain their structural integrity for investigating cell behavior is rarely reported. In this study, we developed and characterized a platform combining native bone surface topography mimicked polydimethylsiloxane (BSM PDMS) surfaces with pre-osteoblast derived dECM to mimic both physical and biochemical cues of the bone microenvironment. Decellularized ECM on PDMS and BSM PDMS surfaces preserved their structure and specific matrix components, in addition to having a significant influence on microscale surface topography. Recellularization of BSM PDMS + dECM surfaces supported cell attachment and proliferation of both pre-osteoblasts and adipose derived mesenchymal stem cells (hADMSC). BSM PDMS + dECM surfaces showed significantly elevated glycosaminoglycan (GAG) content, as well as, resulted in induction and topography dependent calcification of hADMSCs. Osteogenic induction and dECM presence on BSM PDMS synergistically increased RUNX2 expression of hADMSCs while keeping YAP expression relatively unaltered. This work provides insights for designing biomimetic platforms integrating biochemical and biophysical cues for advanced bone tissue engineering.