Figure 4.

In vivo tracking of the migration of ⁸⁹Zr-oxine-labeled CAR-T to A549 and A549-CXCL13 tumors using micro-PET/CT scan

(A) EGFR expression in the A549 cell line stably expressing the CXCL13 gene (A549-CXCL13) after lentiviral transduction and selection. (B) Increased secretion of CXCL13 generated by A549-CXCL13 cells. ∗∗∗p < 0.001. (C) The effects of ⁸⁹Zr-oxine labeling on T cell proliferation. (D) Whole-body PET imaging, quantitative PET analysis, and biodistribution of ⁸⁹Zr-labeled T cells in tumor-bearing mice. ⁸⁹Zr-labeled mock T cells, ⁸⁹Zr-EGFR-CAR-T cells, or ⁸⁹Zr-EGFR-CXCR5-CAR-T cells were tail-vein injected into NSG mice inoculated with A549 tumor cells at the left and A549-CXCL13 tumor cells at the right side. Isotopic distribution of ⁸⁹Zr was quantified and plotted in a coronal horizon map at different time points of 2, 24, 72, and 168 h post-injection. The red and green circles represent the A549 tumor region and A549-CXCL13 tumor region, respectively. (E) Accumulated isotope signaling in A549 tumor region (green circle) and A549-CXCL13 tumor region (red circle). The percentage injection dose rate ([%ID]/g value) was calculated. Error bars represent mean ± SD for each group (n = 3).