Fig. 2
Biodistribution of anti-PD-L1 monoclonal antibody panel. A WT MIH5 antibody and mouse (mIgG1) anti-PD-L1 antibodies were labeled non-site-specifically with DTPA. mIgG1 was labeled site-specifically with IH20 and IH18, where IH20 contains DTPA alone and IH18 contains an additional sulfo-Cy5. B SDS-PAGE analysis of purified site-specifically labeled antibodies. An analytical fraction of mIgG1-IH18 and mIgG1-IH20 was reacted with 5 kDa mPEG-DBCO to analyze purity and azide functionality. This resulted in the near-quantitative conversion to a product of higher molecular weight. (C) Mice bearing orthotopic 4T1 tumors were injected with one of four different 111In-labeled anti-PD-L1 antibodies. Biodistribution was determined ex vivo 24 h after injection. Values are presented as percentage injected dose per gram (%ID/g) and shown as mean ± SD, n = 5