Mapping mechanical stress in curved epithelia of designed size and shape

• Published in: Nature communications Vol. 14; no. 1; p. 4014
• Main Authors: Marín-Llauradó, Ariadna, Kale, Sohan, Ouzeri, Adam, Golde, Tom, Sunyer, Raimon, Torres-Sánchez, Alejandro, Latorre, Ernest, Gómez-González, Manuel, Roca-Cusachs, Pere, Arroyo, Marino, Trepat, Xavier
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 07.07.2023; Nature Publishing Group; Nature Portfolio
• Subjects: 13/107; 631/1647/2204; 639/166/988; 639/766/747; Alignment; Anisotropy; Ellipsoids; Engineers; Epithelium; Geometry; Humanities and Social Sciences; Mammary gland; Mammary glands; Material properties; Monolayers; multidisciplinary; Science; Science (multidisciplinary); Stress; Tensors; Tubes
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-38879-7

The function of organs such as lungs, kidneys and mammary glands relies on the three-dimensional geometry of their epithelium. To adopt shapes such as spheres, tubes and ellipsoids, epithelia generate mechanical stresses that are generally unknown. Here we engineer curved epithelial monolayers of controlled size and shape and map their state of stress. We design pressurized epithelia with circular, rectangular and ellipsoidal footprints. We develop a computational method, called curved monolayer stress microscopy, to map the stress tensor in these epithelia. This method establishes a correspondence between epithelial shape and mechanical stress without assumptions of material properties. In epithelia with spherical geometry we show that stress weakly increases with areal strain in a size-independent manner. In epithelia with rectangular and ellipsoidal cross-section we find pronounced stress anisotropies that impact cell alignment. Our approach enables a systematic study of how geometry and stress influence epithelial fate and function in three-dimensions. Marin-Llaurado and colleagues engineer curved epithelial monolayers of controlled geometry and develop a new technique to map their state of stress. They show that pronounced stress anisotropies influence cell alignment.