| Abstract: | In earlier experiments chemotactic responsiveness of peripheral blood monocytes obtained from patients with head and neck cancers was found to be markedly depressed. In an attempt to attribute this defect in migration to an influence excited by low molecular weight factors of less than 25,000 daltons, derived from the tumor, Amicon filtrates of head and neck cancer cells were administered sub-cutaneously to C3H mice 24 hrs. before the intraperitoneal injection of concanavelin A. Subsequent macrophage accumulation into the peritoneal cavity was quantified. A clear inhibition of macrophage infiltration was found, particularly when filtrates of poorly differentiated tumors were used. Injection of filtrates from healthy oral mucosa were negative, whereas mouse mammary carcinoma filtrates strongly inhibited accumulation. |
