Sixteen male and female patients with alcoholic cirrhosis and 13 healthy controls were included in the study. The level of interferon (IFN) and tumor necrosis factor (TNF) activity was examined in the sera and also in cultures in peripheral blood leukocytes (PBL) after in vitro stimulation with the cytokine inducers. In sera of patients with alcoholic cirrhosis higher IFN and TNF levels were detected than in controls. However, after induction with Newcastle disease virus (NDV), phytohemagglutinin M (PHA) and lipopolysaccharide from E. coli (LPS), PBL from cirrhotic patients produced lower IFN levels in comparison to controls. In contrast to depressed ability to produce IFNs, TNF production was higher in PBL of cirrhotic patients induced by PHA and a low dose of LPS (1 microgram/ml). NDV induced comparable levels of TNF in both groups. It appears likely that cells of cirrhotic patients were suppressed by an unknown factor or were hyporeactive for IFN production, but synthesis and release of TNF was enhanced, suggesting that cells producing TNF were preactivated in vivo. Mechanism of such preactivation is discussed.