Journal: Molecular imaging and biology

Article Title: An analysis of isoclonal antibody formats suggests a role for measuring PD-L1 with low molecular weight PET radiotracers

doi: 10.1007/s11307-020-01527-3

Figure Lengend Snippet: A summary of the kinetic constants for the C4 minibody, scFv and their respective DFO-conjugates. The binding was assayed against the ectodomain of recombinant human PD-L1 using biolayer interferometry. The data are representative of two independent experiments. In the case of the K D and the K dis for the C4 minibody, the constants approached the limit of detection and the instrument was not capable of reporting error calculations.

Article Snippet: Kinetic constants for the minibody and scFv antibody against human and mouse PD-L1 (Sino Biological Inc.) were determined via biolayer interferometry with an Octet RED384 instrument (ForteBio) using a previously described approach[ 11 ].

Techniques: Binding Assay, Recombinant

Journal: Molecular imaging and biology

Article Title: An analysis of isoclonal antibody formats suggests a role for measuring PD-L1 with low molecular weight PET radiotracers

doi: 10.1007/s11307-020-01527-3

Figure Lengend Snippet: A. At left is shown a plot of the blood and tumor activity values for the radiolabeled C4 minibody at several time points after its injection into immunocompetent mice bearing implanted B16F10 tumor cells. Tumor uptake was statistically higher than blood starting from 1.5 hours post injection. Tumor uptake peaked at 1.5 hours and declined from 1.5 to 2.5 hours, which mirrors the behavior we observed with the 89Zr-C4 minibody or IgG1 over a longer window of time. At right are shown transaxial CT and PET/CT taken at 1.5 hours post injection. The tumor is on the left hindlimb. B. At left is shown a plot of the blood and tumor activity values for the radiolabeled C4 scFv at several time points after its injection into nu/nu mice bearing H1975 xenografts. Tumor uptake was statistically higher than blood starting from 0.5 hours post injection. At right are shown transaxial CT and PET/CT taken at 1.5 hours post injection. The tumor is on the left hindlimb. C. Biodistribution data from select normal tissues from C57Bl6/J mice. D. Biodistribution data from select normal tissues from nu/nu mice.

Article Snippet: Kinetic constants for the minibody and scFv antibody against human and mouse PD-L1 (Sino Biological Inc.) were determined via biolayer interferometry with an Octet RED384 instrument (ForteBio) using a previously described approach[ 11 ].

Techniques: Activity Assay, Injection, Positron Emission Tomography-Computed Tomography

Journal: Molecular imaging and biology

Article Title: An analysis of isoclonal antibody formats suggests a role for measuring PD-L1 with low molecular weight PET radiotracers

doi: 10.1007/s11307-020-01527-3

Figure Lengend Snippet: A. DAR and anti-PDL1 immunohistochemistry (co-stained with hematoxylin) of a liver section from a 1 year old female Alb Cre; MYCTg; KRASG12D genetically engineered mouse model of heptacellular carcinoma. Multiple tracer avid foci are detected against the background of normal liver. At right are shown the merged images with the PDL1 immunohistochemistry magnified at 40X in selected fields of view to show the concordance between radiotracer binding and PD-L1 expression in tumor. Additional fields of view and tumor slices are shown in Supplemental Figure 1. B. Biodistribution data showing the uptake of 89Zr-scFv in an orthotopic hepatocellular tumor established from a mouse cell line derived from the Alb Cre; MYCTg; KRASG12D GEM model.

Article Snippet: Kinetic constants for the minibody and scFv antibody against human and mouse PD-L1 (Sino Biological Inc.) were determined via biolayer interferometry with an Octet RED384 instrument (ForteBio) using a previously described approach[ 11 ].

Techniques: Immunohistochemistry, Staining, Binding Assay, Expressing, Derivative Assay