Single cell imaging of Bruton's tyrosine kinase using an irreversible inhibitor

Sci Rep. 2014 Apr 24:4:4782. doi: 10.1038/srep04782.

Abstract

A number of Bruton's tyrosine kinase (BTK) inhibitors are currently in development, yet it has been difficult to visualize BTK expression and pharmacological inhibition in vivo in real time. We synthesized a fluorescent, irreversible BTK binder based on the drug Ibrutinib and characterized its behavior in cells and in vivo. We show a 200 nM affinity of the imaging agent, high selectivity, and irreversible binding to its target following initial washout, resulting in surprisingly high target-to-background ratios. In vivo, the imaging agent rapidly distributed to BTK expressing tumor cells, but also to BTK-positive tumor-associated host cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adenine / analogs & derivatives
  • Agammaglobulinaemia Tyrosine Kinase
  • Animals
  • Binding Sites
  • Cell Line, Tumor
  • Gene Expression
  • Genes, Reporter
  • Heterografts
  • Humans
  • Lymphoma / diagnosis
  • Lymphoma / metabolism
  • Mice
  • Models, Molecular
  • Molecular Conformation
  • Molecular Imaging*
  • Piperidines
  • Protein Binding
  • Protein Kinase Inhibitors / chemistry
  • Protein Kinase Inhibitors / metabolism*
  • Protein Kinase Inhibitors / pharmacology
  • Protein-Tyrosine Kinases / antagonists & inhibitors
  • Protein-Tyrosine Kinases / chemistry
  • Protein-Tyrosine Kinases / metabolism*
  • Pyrazoles / chemistry
  • Pyrazoles / metabolism
  • Pyrazoles / pharmacology
  • Pyrimidines / chemistry
  • Pyrimidines / metabolism
  • Pyrimidines / pharmacology
  • Single-Cell Analysis*

Substances

  • Piperidines
  • Protein Kinase Inhibitors
  • Pyrazoles
  • Pyrimidines
  • ibrutinib
  • Protein-Tyrosine Kinases
  • Agammaglobulinaemia Tyrosine Kinase
  • BTK protein, human
  • Btk protein, mouse
  • Adenine