title: Multiplexed mAbs: a new strategy in preclinical time-domain imaging of acute myeloid leukemia.
abstract: Antibodies play a fundamental role in diagnostic immunophenotyping of leukemias and in cell-targeting therapy. However, this versatility is not reflected in imaging diagnostics. In the present study, we labeled anti–human mAbs monochromatically against selected human myeloid markers expressed on acute myeloid leukemia (AML) cells, all with the same near-infrared fluorochrome. In a novel “multiplexing” strategy, we then combined these mAbs to overcome the limiting target-to-background ratio to image multiple xenografts of AML. Time-domain imaging was used to discriminate autofluorescence from the distinct fluorophore-conjugated antibodies. Imaging with multiplexed mAbs demonstrated superior imaging of AML to green fluorescent protein or bioluminescence and permitted evaluation of therapeutic efficacy with the standard combination of anthracycline and cytarabine in primary patient xenografts. Multiplexing mAbs against CD11b and CD11c provided surrogate imaging biomarkers of differentiation therapy in an acute promyelocytic leukemia model treated with all-trans retinoic acid combined with the histone-deacetylase inhibitor valproic acid. We present herein an optimizedapplication of multiplexed immunolabeling in vivo for optical imaging of AML cellxenografts that provides reproducible, highly accurate disease staging and monitoring of therapeutic effects.
authors.affiliation: Institute of Medicine, Hematology Section, University of Bergen, Bergen, Norway. emmet.mc.cormack@med.uib.no
authors.forename: Emmet
authors.initials: E
authors.lastname: McCormack
authors.forename: Maja
authors.initials: M
authors.lastname: Mujić
authors.forename: Tereza
authors.initials: T
authors.lastname: Osdal
authors.forename: Øystein
authors.initials: Ø
authors.lastname: Bruserud
authors.forename: Bjørn Tore
authors.initials: BT
authors.lastname: Gjertsen
mesh_terms: D000818:Animals; D018943:Anthracyclines / Q000008:administration & dosage; D000911:Antibodies, Monoclonal; D000971:Antineoplastic Combined Chemotherapy Protocols; D039481:CD11b Antigen / Q000378:metabolism; D039521:CD11c Antigen / Q000378:metabolism; D045744:Cell Line, Tumor; D003561:Cytarabine / Q000008:administration & dosage; D005456:Fluorescent Dyes; D049452:Green Fluorescent Proteins; D018922:HL-60 Cells; D006801:Humans; D016130:Immunophenotyping; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis* / Q000188:drug therapy / Q000276:immunology*; D015473:Leukemia, Promyelocytic, Acute / Q000175:diagnosis / Q000188:drug therapy / Q000276:immunology; D008163:Luminescent Measurements; D051379:Mice; D016688:Mice, Inbred NOD; D018345:Mice, Knockout; D016513:Mice, SCID; D061848:Optical Imaging / Q000379:methods; D014212:Tretinoin / Q000008:administration & dosage; D014635:Valproic Acid / Q000008:administration & dosage; D023041:Xenograft Model Antitumor Assays
chemical_list: D018943:Anthracyclines; D000911:Antibodies, Monoclonal; D039481:CD11b Antigen; D039521:CD11c Antigen; D005456:Fluorescent Dyes; C509295:ITGAM protein, human; D003561:Cytarabine; D049452:Green Fluorescent Proteins; D014212:Tretinoin; D014635:Valproic Acid