Additional file 6 of Targeted alpha therapy with astatine-211-labeled anti-PSCA A11 minibody shows antitumor efficacy in prostate cancer xenografts and bone microtumors

Additional file 6: Figure S6. (a) Comparison of bone marrow uptake at 1 hpi of 211At-labeled minibody A11 labeled with the m-Me-ATE-method (described in the paper) as compared to labeling with the B10 boron cage method [28]. (b) Bone marrow-to-Blood-ratio (BMBLR) at 1 hpi. Labeling procedure B-10 .Briefly, the B-10 derivative was conjugated to the antibody as follows: a 10 time excess of the B-10 derivative was added to the antibody at a concentration of 3-4 mg/ml in carbonate buffer pH 8.5. The reaction was allowed to proceed over night at gentle agitation. The conjugated antibody was isolated by passage over a NAP-5 column. The column was eluted with PBS. A dry residue of 211At was activated by 10 μl, 2 nmole NIS in methanol/1% acetic acid. To the At-211/ NIS was then 100 μg, 200 μl B-10-Antibody added under agitation. After 1 minute the reaction was stopped by adding 0.8 μmole sodium ascorbate. Finally, the labeled antibody was isolated by size exclusion chromatography on NAP-5 column. Radiochemical yields was in the range of 65-80% .