FIGURE 1.

(A) ¹¹¹In-H10-TAT was synthesized by conjugation of activated 4-sulfo-2,3,5,6-tetrafluorophenyl ester of dibenzocyclooctyne to mAb, after which click chemistry was used to conjugate azide-DTPA to allow radiolabeling with ¹¹¹In, and azide-TAT peptide for cell penetration. Labeling with ¹¹¹InCl₃ allows detection through its γ-ray emissions and molecular SPECT imaging. (B) Comparison of native H10 with conjugated DTPA-H10-TAT’s ability to block binding of ¹¹¹In-H10 to p53 in fixed and permeabilized p53^R175H-overexpressing FAMPAC cells showed no significant differences. (C) Uptake of ¹¹¹In-H10-TAT was no different from that of ¹¹¹In-mIgG-TAT in 3 different cell lines but far higher than non–TAT-conjugated versions. ***P < 0.001. ****P < 0.0001. DBCO = dibenzocyclooctyne; STP = 4-sulfo-2,3,5,6-tetrafluorophenyl.