[Synergistic activation of rat alveolar macrophages by cepharanthine and OK-432].

We studied the synergistic activation of rat alveolar macrophages (AM) by cepharanthine (Ceph.) and OK-432. Rat AM could be rendered much more tumoricidal against Walker-256 tumors in vitro after the i.v. injection of ceph. (5 mg/Kg) and OK-432 (5 KE/rat) thao of ceph. or OK-432 only. Radioactivity of 14C-acetate-OK-432 trapped in murine lung after the i.v. injection of mixed of ceph. was much higher than of 14C-acetate-OK-432 only. Rat AM could be rendered tumoricidal by incubation in vitro with OK-432, but not with ceph. This finding suggests that if OK-432 is injected intravenously with mixed of with ceph., of OK-432 is trapped much more up by the lung without mixture, therefore AM can be much more tumoricidal. Intravenous administration of OK-432 with ceph. may be useful for reduction of lung metastasis by tumoricidal AM.