Fig. 11. VSVΔG-CHIKV infects distant brain tumors in metastasis model.
A. CB17 SCID mice (n = 5) received bilateral xenografts of rYUMAC melanoma cells expressing RFP. 8 days later, only the tumor on the right side was injected stereotactically with 1 μl (7 × 105 PFU) of VSVΔG-CHIKV. Brains were harvested 8 days later. B, C. Both red (tumor) and green (virus infection) fluorescence were detected in the injected right striatum (C) and in the non-injected left cortex (B). D, E. Analysis of expression of RFP (tumor) and virus immunofluorescence revealed strong viral fluorescence in the right injected striatal tumor (E) and also showed fluorescence associated with the left non-injected striatal tumor in the side of the brain contralateral to the virus injection (D). Scale bar, 0.1 mm. F–H. CB17 SCID mice (n = 3) received bilateral xenografts of rYUMAC melanoma cells expressing RFP. 10 days later, 0.5 μl VSVΔG-CHIKV (7 × 108 PFU) was stereotactically injected on the top of the tumor on both sides of the brain. Tumor (G) and control cerebellum (F) tissue samples were harvested and dissociated 2 and 10 days later and used to inoculate cultures of Vero cells. VSVΔG-CHIKV infection of Vero cells was determined by immunostaining (scale bar, 0.5 mm) and percentages of infected cells are shown in the bar graph (H). Only tumor tissue generated infection on the underlying cells. ***p < 0.001.