Motility of splenic cells from normal and fibrosarcoma-bearing mice in agarose assay

When nonadherent splenic cells from normal and tumor-bearing (mouse fibrosarcoma, MFS) Swiss mice were added to wells made in agarose layers in plastic petri dishes, subpopulations of cells from tumor-bearing mice were seen to migrate out of the wells, whereas those from normal mice did not. The proportion of migratory cells among the lower density (less than 1.057 to less than 1.069 g/ml) cells was larger than that of higher density (1.069 to less than 1.087 g/ml) cells. When the plastic surface underneath the agarose layer was covered with a monolayer of MFS cells, the splenic cells from normal mice also migrated out of the wells. About 20% dead MFS cells were observed in the zone of migration when the migratory cells were from normal mice, and about 30% when the migratory cells were from tumor bearing mice. Apart from revealing the differences between the migratory behavior of splenic cells, the present work also suggests a novel application of agarose methodology in the study of interaction of cytotoxic cells with malignant cells.