The biophysical and compositional properties of human basement membranes

Basement membranes are among the most widespread, non‐cellular functional materials in metazoan organisms. Despite this ubiquity, the links between their compositional and biophysical properties are often difficult to establish due to their thin and delicate nature. In this article, we examine these features on a molecular level by combining results from proteomics, elastic, and nanomechanical analyses across a selection of human basement membranes. Comparing results between these different membranes connects certain compositional attributes to distinct nanomechanical signatures and further demonstrates to what extent water defines these properties. In all, these data underline BMs as stiff yet highly elastic connective tissue layers and highlight how the interplay between composition, mechanics and hydration yields such exceptionally adaptable materials. Basement membranes are exceptionally adaptable materials with both extremely stiff and highly elastic properties. This article highlights these features on a selection of human membranes and links them to compositional, biomechanical, and structural profiles down to a molecular level. The role of water in modulating these attributes is also scrutinized and ultimately highlights that the performance of these materials derives from much more than only the sum of their parts.