Biomimetic Microarray In Exploring The Biomechanics In Odontoblast Polarization

Odontoblast polarization is fundamental to tubular dentin formation, yet its mechanism remains ambiguous, hindering the development of functional dentin regeneration strategies. Cell polarization is featured by cytoskeletal rearrangement, which yields intracellular tension concurrently. However, the revealing of stress on odontoblast polarization remains challenging due to a lack of appropriate study models. With a micropatterning technique, an in vitro single-cell-focused microarray system was generated, which enabled the accommodation of isolated dental pulp stem cells (sDPSCs) and promoted their polarization towards odontoblasts. Polarity indexes, differentiation markers and intracellular tension levels were evaluated on microarrays with sequential areas and tapers to establish the correlation of sDPSCs polarization, differentiation and cell tension. Inhibitors targeting microfilament assembly, microtubule dynamics and cytoskeletal regulators GTPases were added respectively to identify the underlying mechanism. Moreover, a specifically designed mathematical algorithm was developed, which step-by-step modeled the 3D adhesion process of sDPSCs on different microarrays and compared their adhesive forces and intracellular tensions. With six comprehensive polarization-relevant evaluation indexes, our results showed that the area and taper of microarrays modulated cell polarization and differentiation levels simultaneously by regulating cytoskeleton-mediated cellular tension via the vinculin/myosin/YAP pathway. The mathematical model further confirmed that the adhesive force and cell tension were modulated by micropatterning morphology. With the microarray model and the mathematical model, this work verified that odontoblast polarization depends on the mechanical signals generated between an odontoblast and its accommodating microenvironment, mainly via the vinculin/myosin/YAP pathway.