Figure 3.

Restricted infection by oncolytic virus in the absence of physical barriers. Intracranial syngeneic Balb/c mouse DBT gliomas (T) were injected into the same stereotactic coordinates with high-dose oncolytic Semliki Forest virus (SFV) vector VA7. Brains were sampled and stained for SFV antigens 24 h post virus injection (in brown), showing that SFV predominantly infects normal brain parenchymal cells rather than glioma cells. DBT tumors are homogeneous and void of thick extracellular matrix deposits, as seen in Figure 1, arguing that tumor cells resist virus infection by other intracellular means [60].