Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2021 Feb 9;21(4):1223.
doi: 10.3390/s21041223.

Recent Advances in Quenchbody, a Fluorescent Immunosensor

Jinhua Dong  1   2   3 , Hiroshi Ueda  1   2
Affiliations
Review

Recent Advances in Quenchbody, a Fluorescent Immunosensor

Jinhua Dong et al. Sensors (Basel). .

Abstract

The detection of viruses, disease biomarkers, physiologically active substances, drugs, and chemicals is of great significance in many areas of our lives. Immunodetection technology is based on the specificity and affinity of antigen-antibody reactions. Compared with other analytical methods such as liquid chromatography coupled with mass spectrometry, which requires a large and expensive instrument, immunodetection has the advantages of simplicity and good selectivity and is thus widely used in disease diagnosis and food/environmental monitoring. Quenchbody (Q-body), a new type of fluorescent immunosensor, is an antibody fragment labeled with fluorescent dyes. When the Q-body binds to its antigen, the fluorescence intensity increases. The detection of antigens by changes in fluorescence intensity is simple, easy to operate, and highly sensitive. This review comprehensively discusses the principle, construction, application, and current progress related to Q-bodies.

Keywords: antibody; biomarker; detection; fluorescence; immunoassay; quench.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
The working mechanism of Quenchbody. (a) The working model of Quenchbody. Trp residues are shown in light green.; (b) An ELISA to demonstrate the movement of the fluorescent dye on Quenchbody [5].
Figure 2
Figure 2
Quenchbody preparation. (a) Cell-free system for the scFv type. (b) Post labeling method to prepare an ultra-Q-body (UQ-body) with antigen-binding fragment (Fab) produced in E. coli. (c) Method based on transamination at the N-terminus. RS: Rapoport’s salt; p-PDA: p-phenylenediamine.
Figure 3
Figure 3
Quenchbody assays for analyte detection. (a) Schematic image for Quenchbody assay. (b) Detection of fluvoxamine. (c) Detection of deoxynivalenol (DON). (d) Detection of imidacloprid (ICP). (e) Detection of β-amyloid monomer and oligomer (ADDL)s. (f) Detection of claudin 4 (CL4) in PBS and PBS containing 0.05% Tween 20 (PBST). (g) Detection of human epidermal growth factor receptor 2 (HER2) extracellular domain.
Figure 4
Figure 4
Quenchbodies for imaging cells. (a) Bioimaging using Quenchbody; (b,c) Claudin-4 expressed on the membrane of transfected HT1080 cells (b) and LoVo colon cancer cells (c). Reprinted with permission from [38]. Copyright 2017 American Chemical Society. (d) Bone Gla protein produced by vitamin D3-induced U2OS osteosarcoma; (e) HER2 on cancer cells with different HER2 expression levels. Reprinted with permission from [47].
Figure 5
Figure 5
Mini Q-body (a) The scheme of methotrexate (MTX) therapeutic drug monitoring (TDM) based on mini Q-body. (b) Dose-response curves of three mini Q-bodies with a linker at different lengths. Reprinted with permission from [51]. Copyright 2020 American Chemical Society.
Figure 6
Figure 6
(a) Scheme of the structure and use of the PM Q-probe. (b) Results of small molecule detection using the IgG/PM Q-probe complex. The normal concentration range in blood for each dose-response is shown in parentheses. Modified with permission from [52].
See this image and copyright information in PMC

References

    1. Ekins R. More sensitive immunoassays. Nature. 1980;284:14–15. doi: 10.1038/284014a0. - DOI - PubMed
    1. de Picciotto S., Dickson P.M., Traxlmayr M.W., Marques B.S., Socher E., Zhao S., Cheung S., Kiefer J.D., Wand A.J., Griffith L.G., et al. Design Principles for SuCESsFul Biosensors: Specific Fluorophore/Analyte Binding and Minimization of Fluorophore/Scaffold Interactions. J. Mol. Biol. 2016;428:4228–4241. doi: 10.1016/j.jmb.2016.07.004. - DOI - PMC - PubMed
    1. Islam J., Riley B.T., Fercher C., Jones M.L., Buckle A.M., Howard C.B., Cox R.P., Bell T.D.M., Mahler S., Corrie S.R. Wavelength-Dependent Fluorescent Immunosensors via Incorporation of Polarity Indicators near the Binding Interface of Antibody Fragments. Anal. Chem. 2019;91:7631–7638. doi: 10.1021/acs.analchem.9b00445. - DOI - PubMed
    1. Abe R., Ohashi H., Iijima I., Ihara M., Takagi H., Hohsaka T., Ueda H. “Quenchbodies”: Quench-based antibody probes that show antigen-dependent fluorescence. J. Am. Chem. Soc. 2011;133:17386–17394. doi: 10.1021/ja205925j. - DOI - PubMed
    1. Ueda H., Dong J. From Fluorescence Polarization to Quenchbody: Recent Progress in Fluorescent Reagentless Biosensors Based on Antibody and Other Binding Proteins. Biochim. Biophys. Acta Proteins Proteom. 2014;1844:1951–1959. doi: 10.1016/j.bbapap.2014.06.005. - DOI - PubMed

LinkOut - more resources