Effect of cisplatin and FK565 on the activation of tumor-associated and bone marrow-derived macrophages by Dalton's lymphoma.

The present investigations were undertaken to study the effect of Dalton's lymphoma (DL) in situ on the functions of DL-associated macrophages (DL-AM) and bone marrow-derived macrophages (BMDM) in C3H/He mice. DL-AM showed enhanced production of reactive nitrogen intermediates (RNI) and tumor necrosis factor (TNF) compared with normal peritoneal macrophages (NMO). BMDM of DL mice also showed enhanced production of RNI compared with BMDM of normal mice. These observations suggest that the presence of DL in situ creates an environment which favours the activation of both DL-AM and macrophage progenitors located at a distant site. The effect of in vivo administration of chemotherapeutic drugs cisplatin and FK565 on the activation of DL-AM by DL cells was also investigated. Both cisplatin and FK565 augmented RNI production of NMO but differed in their effect on DL-AM. The production of RNI by DL-AM of cisplatin-treated mice was inhibited, whereas in the FK565 group it was up-regulated.