5 research outputs found
FRET Reagent Reveals the Intracellular Processing of Peptide-Linked Antibody–Drug Conjugates
Despite the recent success of antibody–drug
conjugates (ADCs)
in cancer therapy, a detailed understanding of their entry, trafficking,
and metabolism in cancer cells is limited. To gain further insight
into the activation mechanism of ADCs, we incorporated fluorescence
resonance energy transfer (FRET) reporter groups into the linker connecting
the antibody to the drug and studied various aspects of intracellular
ADC processing mechanisms. When comparing the trafficking of the antibody–FRET
drug conjugates in various different model cells, we found that the
cellular background plays an important role in how the antigen-mediated
antibody is processed. Certain tumor cells showed limited cytosolic
transport of the payload despite efficient linker cleavage. Our FRET
assay provides a facile and robust assessment of intracellular ADC
activation that may have significant implications for the future development
of ADCs
FRET Reagent Reveals the Intracellular Processing of Peptide-Linked Antibody–Drug Conjugates
Despite the recent success of antibody–drug
conjugates (ADCs)
in cancer therapy, a detailed understanding of their entry, trafficking,
and metabolism in cancer cells is limited. To gain further insight
into the activation mechanism of ADCs, we incorporated fluorescence
resonance energy transfer (FRET) reporter groups into the linker connecting
the antibody to the drug and studied various aspects of intracellular
ADC processing mechanisms. When comparing the trafficking of the antibody–FRET
drug conjugates in various different model cells, we found that the
cellular background plays an important role in how the antigen-mediated
antibody is processed. Certain tumor cells showed limited cytosolic
transport of the payload despite efficient linker cleavage. Our FRET
assay provides a facile and robust assessment of intracellular ADC
activation that may have significant implications for the future development
of ADCs
Discovery of Peptidomimetic Antibody–Drug Conjugate Linkers with Enhanced Protease Specificity
Antibody–drug
conjugates (ADCs) have become an important
therapeutic modality for oncology, with three approved by the FDA
and over 60 others in clinical trials. Despite the progress, improvements
in ADC therapeutic index are desired. Peptide-based ADC linkers that
are cleaved by lysosomal proteases have shown sufficient stability
in serum and effective payload-release in targeted cells. If the linker
can be preferentially hydrolyzed by tumor-specific proteases, safety
margin may improve. However, the use of peptide-based linkers limits
our ability to modulate protease specificity. Here we report the structure-guided
discovery of novel, nonpeptidic ADC linkers. We show that a cyclobutane-1,1-dicarboxamide-containing
linker is hydrolyzed predominantly by cathepsin B while the valine–citrulline
dipeptide linker is not. ADCs bearing the nonpeptidic linker are as
efficacious and stable in vivo as those with the dipeptide linker.
Our results strongly support the application of the peptidomimetic
linker and present new opportunities for improving the selectivity
of ADCs
Discovery of Peptidomimetic Antibody–Drug Conjugate Linkers with Enhanced Protease Specificity
Antibody–drug
conjugates (ADCs) have become an important
therapeutic modality for oncology, with three approved by the FDA
and over 60 others in clinical trials. Despite the progress, improvements
in ADC therapeutic index are desired. Peptide-based ADC linkers that
are cleaved by lysosomal proteases have shown sufficient stability
in serum and effective payload-release in targeted cells. If the linker
can be preferentially hydrolyzed by tumor-specific proteases, safety
margin may improve. However, the use of peptide-based linkers limits
our ability to modulate protease specificity. Here we report the structure-guided
discovery of novel, nonpeptidic ADC linkers. We show that a cyclobutane-1,1-dicarboxamide-containing
linker is hydrolyzed predominantly by cathepsin B while the valine–citrulline
dipeptide linker is not. ADCs bearing the nonpeptidic linker are as
efficacious and stable in vivo as those with the dipeptide linker.
Our results strongly support the application of the peptidomimetic
linker and present new opportunities for improving the selectivity
of ADCs
Discovery of Peptidomimetic Antibody–Drug Conjugate Linkers with Enhanced Protease Specificity
Antibody–drug
conjugates (ADCs) have become an important
therapeutic modality for oncology, with three approved by the FDA
and over 60 others in clinical trials. Despite the progress, improvements
in ADC therapeutic index are desired. Peptide-based ADC linkers that
are cleaved by lysosomal proteases have shown sufficient stability
in serum and effective payload-release in targeted cells. If the linker
can be preferentially hydrolyzed by tumor-specific proteases, safety
margin may improve. However, the use of peptide-based linkers limits
our ability to modulate protease specificity. Here we report the structure-guided
discovery of novel, nonpeptidic ADC linkers. We show that a cyclobutane-1,1-dicarboxamide-containing
linker is hydrolyzed predominantly by cathepsin B while the valine–citrulline
dipeptide linker is not. ADCs bearing the nonpeptidic linker are as
efficacious and stable in vivo as those with the dipeptide linker.
Our results strongly support the application of the peptidomimetic
linker and present new opportunities for improving the selectivity
of ADCs