Abstract
The intraperioneal administration of β-subunit prepared from egg white ovomucin was found to suppress the growth of subcutaneously xenografted sarcoma-180 cells in mice and cure the tumor. In the present system, β-subunit (5 mg/kg of body weight) was injected to mice daily for 19 days after the 10th day when tumors had grown to 7 mm in diameter. The light and electron microscopic appearances of tumor portions on day 28 showed that β-subunit-treated tumor cells were in the states of degenerated and necrotic cells, and massive accumulations of neutrophils, macrophages and lymphocytes were found at the margin of the degenerated and necrotic tumor tissue area. These findings suggested that β-subunit brought about the regression of tumor, probably by activating the immune system.
