Macrophage-like cells as research tools in transfer experiments.

Transfer experiments with macrophages are only possible to a limited extent in mice as this kind of experiment usually requires large numbers of macrophages. The usual source of macrophages is the peritoneal cavity, which yields on the average only 2-20 x 10(6) macrophages per mouse. Instead, we now use for transfer experiments macrophage-like cells, such as the macrophage tumors WEHI-3, J774A and P388D1. To prevent replication after transfer, the cells can be treated with mitomycin-C. Our data illustrate that these macrophage-like cells can co-operate with sensitized lymphocytes in the eradication of lymphosarcoma cells in a fashion similar to macrophages (1). The vast amount of available data on properties of these cells (2) will allow to correlate their macrophage properties with in-vivo function.