Leveraging advanced technologies to optimize in vitro biophysical stimulation experiments

This thesis investigates the impact of biophysical stimuli on bone tissue regeneration using advanced in vitro models. Chapter 1: Introduces a novel bioreactor combining fluid flow shear stress and pulsed electromagnetic fields (PEMF) for 3D bone tissue culture. Computational simulations optimize the system, and preliminary experiments with human bone marrow-derived mesenchymal stem cells (hBMSCs) assess the osteogenic potential of these stimuli. Chapter 2: Develops 3D-printed polylactic acid (PLA) scaffolds mimicking trabecular bone. Experiments with hBMSCs on these scaffolds (PLA600) optimize cell seeding methods and culture conditions for enhanced sensitivity to PEMF stimulation. Chapter 3: Explores the molecular and cellular effects of PEMF stimulation on hBMSCs cultured under shear stress using transcriptomic analysis. This aims to elucidate the signaling pathways involved in PEMF-induced bone healing. Chapter 4: Upgrades the bioreactor to incorporate intermittent hydrostatic pressure, simulating physiological loading/unloading. Experiments on PLA600 scaffolds with hBMSCs assess cell viability under these bone-like mechanical stimuli. Chapter 5: Introduces a new set of 3D-printed biomimetic PLA scaffolds (P3S3) resembling the ulna, tibia, and femur. Experiments with hBMSCs evaluate cell viability and gene expression changes under fluid shear stress with and without intermittent hydrostatic pressure, mimicking in-patient rehabilitation. This research provides valuable insights into the cellular and molecular effects of biophysical stimulation on bone regeneration, enhancing in vitro models and reducing animal use in research.