Guidance of cellular nematic elastomers into shape-programmable living surfaces

Engineering living materials that autonomously morph into predetermined shapes holds potential for synthetic morphogenesis and soft robotics. Harnessing cellular tissues to self-organize and generate forces offers a promising route toward this goal. However, controlling tissue mechanics to direct morphogenesis remains challenging. We introduce a strategy to program tissue-shape transformations through nematic organization of cellular forces. By controlling nematic order and topological defects, we generate tissues programmed with specific stress fields. Using a theoretical framework coupling contractile nematics with thin-sheet mechanics, we show that nematically guided active stresses can drive morphogenesis through Gaussian morphing. Experimentally, detachment of nematic tissues triggers out-of-plane deformations, generating reproducible three-dimensional shapes. Integrating contractility and nematic patterning, our approach establishes a framework for designing shape-programmable living surfaces.