Assay for macrophage-mediated anti-tumor cytotoxicity

This unit describes a procedure for determining ability of mouse macrophages to lyse tumor cells in vitro. The Basic Protocol outlines a three-stage assay that includes: (1) culture of macrophages (freshly explanted from mice or grown from a cell line) with suspected activating reagents; (2) extensive washing of the cultured macrophages to remove residual reagents, followed by incubation with [(111)In]-labeled tumor cells to allow lysis to occur; and (3) collection of cell-free culture supernatants and measurement of cytolytic activity as a function of (111)In released from tumor cells destroyed by activated macrophages. The Support Protocol outlines a method for radiolabeling tumor cells with [(111)In]oxine.