Migration of genetically labeled glioma cells after implantation into murine brain

Abstract
Murine RSV‐M glioma cells were genetically labeled with a retroviral BAG vector carrying the Escherichia coli β‐galactosidase gene. The X‐gal‐positive stable cell line RSV‐M/BAG was obtained by the FDG‐FACS method. To examine the behavior of glioma cells in the brain, we homografted RSV‐M/BAG cells into the brain of C3H/HeN mice as cell suspensions. Individual grafted glioma cells were easily detected by histochemical staining for B‐galactosidase (β‐gal). Three days after grafting, the β‐gal‐positive cells were mainly found in the subependymal zone of the lateral ventricle. In addition, some solitary labeled cells were found at locations distant from the injection sites. On the seventh day after implantation, tumor masses were observed and graft‐derived glioma cells were migrating bilaterally along the fibers in the corpus callosum. Other labeled cells extended into the brain parenchya via the perivascular (Virchow‐Robin) spaces. Rapid and extensive migration of individual glioma cells was thus clearly demonstrated by intracerebral transplantation of RSV‐M/BAG cells.