doi:10.1002/anie.202216142engCheng, ZhimingThompson, Emily JMendive-Tapia, LorenaScott, Jamie IBenson, SamKitamura, TakanoriSenan-Salinas, AnaSamarakoon, YouhaniRoberts, Edward WArias, Maykel APardo, JulianGalvez, Eva MVendrell, MarcFluorogenic Granzyme A Substrates Enable Real-Time Imaging of Adaptive Immune Cell ActivityART-2022-135428Cytotoxic immune cells, including T lymphocytes (CTLs) and natural killer (NK) cells, are essential components of the host response against tumors. CTLs and NK cells secrete granzyme A (GzmA) upon recognition of cancer cells; however, there are very few tools that can detect physiological levels of active GzmA with high spatiotemporal resolution. Herein, we report the rational design of the near‐infrared fluorogenic substrates for human GzmA and mouse GzmA. These activity‐based probes display very high catalytic efficiency and selectivity over other granzymes, as shown in tissue lysates from wild‐type and GzmA knock‐out mice. Furthermore, we demonstrate that the probes can image how adaptive immune cells respond to antigen‐driven recognition of cancer cells in real time.2022http://zaguan.unizar.es/record/12941110.1002/anie.202216142http://zaguan.unizar.es/record/129411oai:zaguan.unizar.es:129411info:eu-repo/grantAgreement/ES/AEI/PID2020-113963RB-I00info:eu-repo/grantAgreement/ES/DGA/B29-20Rinfo:eu-repo/grantAgreement/EC/H2020/859908/EU/Novel Applications in 19F Magnetic Resonance Imaging/NOVA-MRIThis project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 859908-NOVA-MRIinfo:eu-repo/grantAgreement/ES/MCIU-AEI/SAF2017-83120-C2-1-RANGEWANDTE CHEMIE-INTERNATIONAL EDITION 62, 8 (2022), e202216142 [7 pp.]byhttp://creativecommons.org/licenses/by/3.0/es/info:eu-repo/semantics/openAccess