Cytotoxic assays of sera of tumor-bearing patients and inhibition of monocyte and granulocyte spreading activities.

Sera of patients with solid tumors showed cytotoxic antibodies against a selected panel of lymphocyte and granulocyte donors, typed for HLA antigens. The same sera were also studied for soluble circulating immune complexes and for the capability of inhibiting granulocyte and monocyte spreading. The percentage of rosette forming cells was also measured in the majority of patients. Some alterations of these immunologic parameters were significantly correlated with the presence of granulocytotoxic antibodies. These results suggested that some unknown factors in sera from patients with neoplasms may interfere with host-defence mechanisms, but the role played by cytotoxins needs further clarification.