Dynamic matrices with DNA-encoded viscoelasticity for advanced cell and organoid culture

3D cell and organoid cultures, which allow in vitro studies of organogenesis and carcinogenesis, rely on the mechanical support of viscoelastic matrices. However, commonly used matrix materials lack rational design and control over key cell-instructive properties. Herein, we report a class of fully synthetic hydrogels based on novel DNA libraries that self-assemble with ultra-high molecular weight polymers, forming a dynamic DNA-crosslinked matrix (DyNAtrix). DyNAtrix enables, for the first time, computationally predictable, systematic, and independent control over critical viscoelasticity parameters by merely changing DNA sequence information without affecting the compositional features of the system. This approach enables: (1) thermodynamic and kinetic control over network formation; (2) adjustable heat-activation for the homogeneous embedding of mammalian cells; and (3) dynamic tuning of stress relaxation times over several orders of magnitude, recapitulating the mechanical characteristics of living tissues. DyNAtrix is self-healing, printable, exhibits high stability, cyto-and hemocompatibility, and controllable degradation. DyNAtrix-based 3D cultures of human mesenchymal stromal cells, pluripotent stem cells, canine kidney cysts, and human placental organoids exhibit high viability (on par or superior to reference matrices), proliferation, and morphogenesis over several days to weeks. DyNAtrix thus represents a programmable and versatile precision matrix, paving the way for advanced approaches to biomechanics, biophysics, and tissue engineering. ![Figure][1] ### Competing Interest Statement E.K., Y.-H.P., K.G., and S.K.H. have filed a patent application for various aspects of this work. * AA : Polyacrylamide CCL : Combinatorial crosslinker library CGC : Critical gelation concentration DyNAtrix : Dynamic DNA-crosslinked matrix ECM : Extracellular matrix F1+2 : Prothrombin fragment 1+2 FBS : Fetal bovine serum HAC : Heat-activated crosslinker hiPSC : Human induced pluripotent stem cell hTSC : Human trophoblast stem cell MDa : Megadalton MDCK : Madin-Darby canine kidney MSC : Mesenchymal stem cell nt : nucleotide PF4 : Platelet factor 4 RGD : Arginylglycylaspartic acid SRC : Stress-relaxation crosslinker UHMW : Ultra-high molecular weight w/v : weight to volume ratio [1]: pending:yes