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Antibody-Linked Fluorogen-Activating Proteins for Antigen Detection and Cell Ablation.

ABSTRACT: We demonstrate selective labeling of cell surface proteins using fluorogen-activating proteins (FAPs) conjugated to standard immunoglobulins (IgGs). Conjugation was achieved with a polypeptide reagent comprised of an N-terminal photoactivatable Fc-binding domain and a C-terminal FAP domain. The resulting FAP-antibody conjugates were effective agents for protein detection and cell ablation in cultured mammalian cells and for visualizing cell-cell contacts using a tethered fluorogen assay. Because our approach allows FAP-antibody conjugates to be generated for most currently available IgGs, it should have broad utility for experimental and therapeutic applications.

SUBMITTER: Ackerman DS

PROVIDER: S-EPMC7067197 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Antibody-Linked Fluorogen-Activating Proteins for Antigen Detection and Cell Ablation.

Ackerman Daniel S DS Altun Burcin B Kolodieznyi Dmytro D Bruchez Marcel P MP Tsourkas Andrew A Jarvik Jonathan W JW

Bioconjugate chemistry 20181226 1

We demonstrate selective labeling of cell surface proteins using fluorogen-activating proteins (FAPs) conjugated to standard immunoglobulins (IgGs). Conjugation was achieved with a polypeptide reagent comprised of an N-terminal photoactivatable Fc-binding domain and a C-terminal FAP domain. The resulting FAP-antibody conjugates were effective agents for protein detection and cell ablation in cultured mammalian cells and for visualizing cell-cell contacts using a tethered fluorogen assay. Because ...[more]

PMID: 30543409

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