Signals from the microenvironment around a cell are known to influence cell behavior. Material properties, such as biochemical composition and substrate stiffness, are today accepted as significant regulators of stem cell fate. The knowledge of how cell behavior is influenced by 3D geometric cues is, however, strongly limited despite its potential relevance for the understanding of tissue regenerative processes and the design of biomaterials. Here, the role of surface curvature on the migratory and differentiation behavior of human mesenchymal stem cells (hMSCs) has been investigated on 3D surfaces with well‐defined geometric features produced by stereolithography. Time lapse microscopy reveals a significant increase of cell migration speed on concave spherical compared to convex spherical structures and flat surfaces resulting from an upward‐lift of the cell body due to cytoskeletal forces. On convex surfaces, cytoskeletal forces lead to substantial nuclear deformation, increase lamin‐A levels and promote osteogenic differentiation. The findings of this study demonstrate a so far missing link between 3D surface curvature and hMSC behavior. This will not only help to better understand the role of extracellular matrix architecture in health and disease but also give new insights in how 3D geometries can be used as a cell‐instructive material parameter in the field of biomaterial‐guided tissue regeneration.

Reproduction of the anatomical structures and functions of tissues using cells and designed 3D scaffolds is an ongoing challenge. For this, scaffolds with appropriate biomorphic surfaces promoting cell attachment, proliferation and differentiation are needed. In this study, eight triply-periodic minimal surface (TPMS)-based scaffolds were designed using specific trigonometric equations, providing the same porosity and the same number of unit cells, while presenting different surface curvatures. The scaffolds were fabricated by stereolithography using a photocurable resin based on the biocompatible, biodegradable and rubber-like material, poly(trimethylene carbonate) (PTMC). A numerical approach was developed to calculate the surface curvature distributions of the TPMS architectures. Moreover, the scaffolds were characterized by scanning electron microscopy, micro-computed tomography and water permeability measurements. These original scaffold architectures will be helpful to decipher the biofunctional role of the surface curvature of scaffolds intended for tissue engineering applications.