Single cell imaging of Bruton's tyrosine kinase using an irreversible inhibitor.
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.
1] Center for Systems Biology, Massachusetts General Hospital, 185 Cambridge St, CPZN 5206, Boston, MA 02114 [2].
Anna
A
Turetsky
1] Center for Systems Biology, Massachusetts General Hospital, 185 Cambridge St, CPZN 5206, Boston, MA 02114 [2].
Eunha
E
Kim
Center for Systems Biology, Massachusetts General Hospital, 185 Cambridge St, CPZN 5206, Boston, MA 02114.
Rainer H
RH
Kohler
Center for Systems Biology, Massachusetts General Hospital, 185 Cambridge St, CPZN 5206, Boston, MA 02114.
Miles A
MA
Miller
1] Center for Systems Biology, Massachusetts General Hospital, 185 Cambridge St, CPZN 5206, Boston, MA 02114 [2] Department of Systems Biology, Harvard Medical School, 200 Longwood Ave, Boston, MA 02115.
Ralph
R
Weissleder
D000225:Adenine / Q000031:analogs & derivatives; D000077329:Agammaglobulinaemia Tyrosine Kinase; D000818:Animals; D001665:Binding Sites; D045744:Cell Line, Tumor; D015870:Gene Expression; D017930:Genes, Reporter; D064593:Heterografts; D006801:Humans; D008223:Lymphoma / Q000175:diagnosis / Q000378:metabolism; D051379:Mice; D008958:Models, Molecular; D008968:Molecular Conformation; D057054:Molecular Imaging; D010880:Piperidines; D011485:Protein Binding; D047428:Protein Kinase Inhibitors / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D011720:Pyrazoles / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D011743:Pyrimidines / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D059010:Single-Cell Analysis
D010880:Piperidines; D047428:Protein Kinase Inhibitors; D011720:Pyrazoles; D011743:Pyrimidines; C551803:ibrutinib; D011505:Protein-Tyrosine Kinases; D000077329:Agammaglobulinaemia Tyrosine Kinase; C000625949:BTK protein, human; C000625951:Btk protein, mouse; D000225:Adenine