Adjuvant and antitumor activities of Nocardia cell-wall skeletons.

The adjuvant activity of the cell-wall skeletons prepared from eight species (ten strains) of Nocardia was determined by Brunner's method using allogeneic cell-mediated cytotoxicity test. The antitumor activity of the cell-wall skeleton of N. rubra, which showed the most potent adjuvant activity, was examined using EL-4 leukemia and MH-134 hepatoma cells in syngeneic mice. Its results suggest that the cell-wall skeleton of N. rubra is more potent than BCG cell-wall skeleton as the immunotherapeutic agent for cancer immunotherapy in man. The chemical properties of the cell-wall skeleton of N. rubra were also described.