β-Galactosidase-Catalyzed Fluorescent Reporter Labeling of Living Cells for Sensitive Detection of Cell Surface Antigens

Katsuya Noguchi, Takashi Shimomura, Yuya Ohuchi, Munetaka Ishiyama, Masanobu Shiga, Takeshi Mori, Yoshiki Katayama, Yuichiro Ueno

Research output: Contribution to journalArticle

Abstract

The ability to detect cell surface proteins using fluorescent-dye-labeled antibodies is crucial for the reliable identification of many cell types. However, the different types of cell surface proteins used to identify cells are currently limited in number because they need to be expressed at high levels to exceed background cellular autofluorescence, especially in the shorter-wavelength region. Herein we report on a new method, quinone methide-based catalyzed labeling for signal amplification (CLAMP), in which the fluorescence signal is amplified by an enzymatic reaction that strongly facilitates the detection of cell surface proteins on living cells. We used β-galactosidase as an amplification enzyme and designed a substrate for it, called MUGF, that contains a fluoromethyl group. Upon removal of the galactosyl group in MUGF by β-galactosidase labeling of the target cell surface proteins, the resulting product containing the quinone methide group was found to be both cell-membrane-permeable and reactive with intracellular nucleophiles, thereby providing fluorescent adducts. Using this method, we successfully detected several cell surface proteins, including programmed death ligand 1 protein, which is difficult to detect using conventional fluorescent-dye-labeled antibodies.

Original languageEnglish
Pages (from-to)1740-1744
Number of pages5
JournalBioconjugate Chemistry
Volume31
Issue number7
DOIs
Publication statusPublished - Jul 15 2020

All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Bioengineering
  • Biomedical Engineering
  • Pharmacology
  • Pharmaceutical Science
  • Organic Chemistry

Fingerprint Dive into the research topics of 'β-Galactosidase-Catalyzed Fluorescent Reporter Labeling of Living Cells for Sensitive Detection of Cell Surface Antigens'. Together they form a unique fingerprint.

  • Cite this