Human blood monocyte activation by Nocardia rubra cell wall skeleton for productions of interleukin 1 and tumor necrosis factor-alpha.

Human blood monocytes were obtained from peripheral blood of healthy donors by counter-flow centrifugal elutriation. Functional integrity of monocytes for production of interleukin 1 (IL-1) and tumor necrosis factor alpha (TNF-alpha) in response to Nocardia rubra cell wall skeleton (N-CWS) was examined by bioassay and enzyme immunoassay. Monocytes treated with N-CWS at more than 0.5 microgram/ml produced IL-1 and TNF-alpha extracellularly. Extracellular TNF activity appeared within 4 h, and maximally, 16 h after N-CWS stimulation, whereas longer time was needed for IL-1 activity to appear, the peak production being at 24 h. The neutralizing experiment also showed that anti TNF-alpha antibody did not affect IL-1 production by the monocytes treated with N-CWS, suggesting independency of IL-1 production of TNF-alpha. These results suggest that the therapeutic antitumor effect of N-CWS is due, in part at least, to the augmented production of these monokines.