Figure 5.

Treating spontaneous metastases with self-homing theranostic CTCs: Spontaneous metastases were visualized with RLuc BLI on day 19 and CTCs with FLuc BLI on days 14 and 20 (A). Mice receiving 4T1BR5-CD cells had significantly lower metastatic burden than 4T1 only mice at day 19 (A-B). In the two control mice (4T1BR5-Fluc) that reached endpoint, FLuc CTCs were visualized in the same location as RLucexpressing spontaneous metastases (yellow arrows) as well as at new sites throughout the body (A). We hypothesized that the reduced overlap in RLuc and FLuc signals in these experiments may be due to less RLuc tumor burden in this latter cohort of mice compared to mice in the previous experiment shown in Figure 2, leading to less established sites for the CTCs to home. Comparing the RLuc signal between the two cohorts of mice revealed a significantly lower signal in the latter group (D).