Amplification by Cyclic Extension (ACE): A Next-Generation DNA-Based Signal Amplification for Mass Cytometry

Amplification by Cyclic Extension (ACE) is an advanced DNA-based signal amplification strategy designed to enhance sensitivity in mass cytometry and single-cell analysis. In this method, antibodies are conjugated to short DNA oligonucleotides that serve as primers. Following antigen binding, these DNA tags undergo thermal cyclic extension directly in situ, generating elongated DNA strands that contain multiple hybridization sites for subsequent detector probes.

This cyclic extension process effectively transforms each antibody–antigen complex into a molecular amplification scaffold, allowing the binding of many signal reporters to a single recognition event. Unlike conventional enzymatic or fluorophore-based amplification, ACE offers precise and controllable amplification cycles, which can be optimized for linear or exponential signal increase without compromising spatial integrity.

The ACE approach enables ultra-sensitive single-cell detection, dramatically improving resolution for low-abundance protein targets in heterogeneous cell populations. Its compatibility with DNA-tagged antibodies and multiplexed detection systems positions ACE as a pioneering bridge between molecular biology and cytometric analysis. Furthermore, this DNA-based amplification principle holds promise for adaptation to fluorescence flow cytometry and imaging applications, potentially extending its impact beyond mass cytometry to broader high-resolution analytical platforms.