Chromatin accessibility of genomic regions in human mesenchymal stem cells cultured in sliding hydrogels (SGs) and chemical hydrogels (CGs) undergoing chondrogenesis.

Cells can deform their local microenvironment by exerting forces through pushing and pulling. Such interactions result in behaviors such as cell spreading, cell migration, or cell volume expansion, which occur on timescales of hours to days. However, whether cells can deform local niches at shorter timescales and how such interactions impact long-term cell fates remain largely unknown. Here we report “cell dancing”- a previously unknown cell behavior characterized by seconds-to-minutes scale deformation of the pericellular niche and enhanced cytoskeletal and nuclear dynamics. Using hydrogels that allow cells to deform their local 3D niche and mesenchymal stem cell chondrogenesis as a model system, we identify early-stage cell dancing essential for enhancing stem cell differentiation in 3D. This is mediated through nuclear mechanotransduction pathways that repress global chromatin accessibility, which is necessary for cell dancing-enhanced differentiation. We further demonstrate that cell dancing induces nuclear deformations and phospholipase A2 (PLA2) signaling, and small molecules targeting this pathway can further boost stem cell chondrogenesis. Finally, we validate that cell dancing can enhance stem cell differentiation towards multiple lineages and occurs in other commonly used hydrogel systems. These results establish cell dancing as a novel cell behavior in 3D that may be broadly applied to promote desirable cell fates and tissue outcomes.