Co-Localization-Gated Multivalent DNA Logic Gate for Programmable Cell Recognition.
TL;DR
This work presents a programmable molecular device that integrates Boolean logic computation with spatial confinement to overcome limitations in affinity, specificity, and off-target binding, and demonstrates a strategy for programming high-fidelity molecular interactions on interested cell surfaces.
Abstract
Achieving precise and robust cell-surface recognition in complex biological environments is challenging due to inherent trade-offs in affinity, specificity, and off-target binding. Herein, we present a programmable molecular device that integrates Boolean logic computation with spatial confinement to overcome these limitations. Our system employs valence-controllable, split DNAzyme modules assembled on a tetrahedral DNA nanostructure (TDN). The peroxidase-mimicking activity is stringently gated by a cell-surface AND logic, requiring the co-localization of two adjacent modules on target protein clusters for activation. This spatial constraint effectively eliminates stochastic or unintended signal leakage originating from solution-phase reactions or nontarget cells. Upon activation, the DNAzyme catalyzes the biotinylation of neighboring membrane protein clusters, generating stable multivalent adhesion sites. Quantitative dissociation kinetics reveal that the trivalent design of the DNAzyme modules promotes highly cooperative binding, resulting in uniform, long-lived complexes on target cells. We demonstrate that this approach enables specific recognition and highly efficient isolation of target cells from mixed cell populations and clinical samples, showcasing a strategy for programming high-fidelity molecular interactions on interested cell surfaces.