Depression of monocyte-mediated cytotoxicity by renal carcinoma and restoration through therapy

The cytotoxic ability of freshly isolated monocytes against the tumor cell line K-562 was severely depressed in patients with renal cell carcinoma. The impaired cytotoxicity was partly restored 2 weeks after nephrectomy. Production of monocyte-activating lymphokine, measured as ability to activate tumor cytotoxicity in control monocytes, was depressed in lymphocytes from patients with tumor burden. The impaired lymphokine production seemed to be due to factors in patient serum. Patient monocytes showed an impaired ability to be activated by lymphokines. Products from patient lymphocytes were not able to activate the tumor cytotoxicity of patient monocytes.