Fig. 4.

BC31M4 selectively accumulates in tumors and exhibits superior PK properties in C57-hCD47/hSIRPα mice. a Schematic diagram showing the tumor inoculation and antibody treatment of mice in (b, c). C57-hCD47/hSIRPα mice were s.c. inoculated with E.G7-hCD47 cells on the right lower flank. Mice were i.p. treated with Cy7-labeled antibodies or PBS. b Antibody distribution in mice, monitored by in vivo fluorescence imaging at the indicated time points after the maintenance dose (5 mg/kg). Hair on the back of mice was removed before imaging. Green circles indicate the location of tumors. c Antibody distribution in tumors and different organs of mice (n = 5 per group); tumors and organs were isolated for ex vivo fluorescence imaging at 3 h and 72 h after the maintenance dose. Representative images from one mouse in each group are shown. d Summary of the antibody distribution in tumors and organs of (c), the average quantified radiant efficiency is shown. e Summary of the tumor-to-organ fluorescence intensity ratio of (c). f PK analysis of antibodies in C57-hCD47/hSIRPα mice (n = 2–4 per group). Mice were treated i.p. with a priming dose of 1 mg/kg two days before delivery of a single dose of 20 mg/kg. The antibody concentration in serum was monitored, and the half-life of each antibody is indicated