biostudies-literatureUnknown14Ye J<h4>Objectives</h4>C1s activation is associated with the pathogenesis of various diseases, indicating the potential value of C1s activation detection in clinic. Here we aimed to establish fluorescence resonance energy transfer (FRET)-based immunoassay for the quantitative detection of activated C1s in serum.<h4>Methods</h4>FRET-based fluorogenic peptides, sensitive to the enzymatic activity of activated C1s, were prepared and labeled with the fluorophore ortho-aminobenzoic acid (Abz) and quencher 2,4-dinitrophenyl (Dnp), and then were further selected depending on its Kcat/Km value. C1s in the samples was captured and separated using anti-C1s-conjugated magnetic microbeads. Next, enzymatic activity of activated C1s in samples and standards was examined using fluorescent quenched substrate Frontiers in immunology1081793https://www.ebi.ac.uk/biostudies/studies/S-EPMC9904206biostudies-literatureQuantitative fluorescence resonance energy transfer-based immunoassay for activated complement C1s.PMC9904206Zhu LXia SZhang CXu JYe JfalseQuantitative fluorescence resonance energy transfer-based immunoassay for activated complement C1s.<h4>Objectives</h4>C1s activation is associated with the pathogenesis of various diseases, indicating the potential value of C1s activation detection in clinic. Here we aimed to establish fluorescence resonance energy transfer (FRET)-based immunoassay for the quantitative detection of activated C1s in serum.<h4>Methods</h4>FRET-based fluorogenic peptides, sensitive to the enzymatic activity of activated C1s, were prepared and labeled with the fluorophore ortho-aminobenzoic acid (Abz) and quencher 2,4-dinitrophenyl (Dnp), and then were further selected depending on its Kcat/Km value. C1s in the samples was captured and separated using anti-C1s-conjugated magnetic microbeads. Next, enzymatic activity of activated C1s in samples and standards was examined using fluorescent quenched substrate 2023-01-01T00:00:00Z20232025-04-04T18:43:46.888Z2025-04-04T18:43:46.888ZS-EPMC99042063676173210.3389/fimmu.2023.1081793