Figure 3. Added atezo carrier substantially elevates 89Zr-atezo uptake in H1975 tumors in the T cell deficient nu/nu background.
A. A summary of the biodistribution values for 89Zr-atezo co-injected with 15x molar excess unlabeled atezo in nu/nu mice with subcutaneous H1975 tumors. As with the study in immunocompetent mice, radiotracer uptake was suppressed in PD-L1 rich normal tissues, and elevated in the tumor. The biodistribution data were collected 48 hours post injection. 89Zr-atezo was prepared at a specific activity of 2.5 μCi/μg prior to use with or without added atezo. *P<0.01 B. A bar graph representing the percent change in radiotracer uptake due to added carrier among the immunocompetent and immunocompromised mouse cohorts. Suppression of 89Zr-atezo uptake in normal mouse tissues by carrier atezo was substantial and equivalent among two mouse strains.