Selectivity of TR66-LV in vivo. (A) Strategy for backgating of GFP⁺ cells generated in PBMC-NSG mice of Figure 5. All viable single GFP⁺ cells were assessed for expression of human CD45, CD3, and CD19. (B-D) Scatter plots for the percentages of GFP⁺ cells in the indicated fractions of peritoneum (B), blood (C), and spleen (D). Data are mean ± SD from n = 3 animals per group. ****P < .0001 by 1-way ANOVA with Sidak's correction.