Abstract

To evaluate the possibility that depressed natural killer (NK) cell activity observed in chronic liver diseases might be related to the development of primary hepatocellular carcinoma (PHC), we studied NK cell activity by using 4-hr 51Cr releasing assay in patients with chronic liver diseases caused by chronic B virus infection. The subjects were consisted of hepatitis B virus (HBV) healthy carrier (n=35), chronic active hepatitis (CAH, n=40), liver cirrhosis (LC, n=28), PHC (n=35) and normal control (n=40). The results were as follows: 1) NK cell activity obtained in patients with CAH (51.04+-10.42%,) was similar to that of control group (50.73+7.77%). 2) NK cell activity in HBV carrier (55.07+-11.35%) was some what higher than that of control, but there was no significant difference between the two groups. 3) NK cell act.ivity observed in both groups of patients with LC (40.60+-12.26%) and with PHC (41. 00+-12.20%) were significantly (p<0.005) depressed as compared to those of CAH and control. There was no significant difference in NK cell activity between groups of LC and PHC. These findings might be a suggestion that depressed natural immune surveillance as measured by NK cell activity might be one of several factors which may enhance the development of PHC form cirrhotic liver.