Figure 6.

Effects of PMA on ⁸⁹Zr-PD-1 IgG biodistribution and tumor PD-1 expression. (a) ⁸⁹Zr-PD-1 IgG uptake in organs of EL4 tumor-bearing mice treated with vehicle (control) or PMA. The blocking group was conjected with excess cold anti-PD-1 antibody. (b) Immunoblots of tumor tissue from the above animals for PD-1 protein and band intensities corrected by β-actin. All bars represent the mean ± SD of quadruple mice per group. ^∗P < 0.05 and ^†P < 0.005. (c) Correlation between tumor PD-1 content and tumor ⁸⁹Zr-PD-1 IgG uptake level. Data from two separate experiments include eight mice of the control group (empty circle), eight of the blocking group (filled circle), and four of the PMA group (red circle). The solid line denotes the linear regression, and dotted lines indicate the 95% confidence range.