Antibody-dependent cellular cytotoxicity in critically ill surgical patients

A population of lymphocytes attacks nucleated target cells in the presence of antitarget cell antibody. The cells are known as "killer" (K) cells and the reaction is known as antibody-dependent cellular cytotoxicity. We determined K-cell activity in 70 critically ill surgical patients in order to determine its value in predicting death or survival. Lymphocytes were obtained from the peripheral blood of the patients; murine P-815 mastocytoma cells were used as target cells and antimastocytoma cell IgG antibody was prepared in the rabbit. The initial value of K-cell activity was decreased by 58% in patients who later died; the value was normal in survivors. In septic patients, the decrease was the same in those who lived and those who died. The final value was 64% lower than the initial value in those who died. Therefore, a low initial value and further decrease signified the likelihood of death. Peripheral nutritional alimentation had no effect on K-cell activity. Central alimentation produced a sixfold increase in patients who had > 50% decrease before treatment, but had no effect in those who had normal activity initially. It was concluded that K-cell activity of peripheral blood lymphocytes is a sensitive indicator of the immune status of surgical patients, that it is useful in monitoring the course of the disease, and that central alimentation causes an increase in immunosuppressed patients.