[Functional activity of natural killers in viral hepatitis A].

The direct cytotoxic test with the use of C and neoplastic cells of human myeloleukemia K-562 was employed to examine the activity of natural killers (NK) in 234 patients with viral hepatitis and in 51 healthy subjects as control. It was ascertained that in viral hepatitis, the functional activity of NK was appreciably altered. At the disease onset it tended toward lowering, whereas before the recovery it consistently increased. In cyclic hepatitis, the cytotoxicity rose considerably 2 to 3 weeks after the disease onset. In a mild disease, the growth of the cytotoxicity started much earlier and was pronounced to a greater degree than in conditions of medium severity or in grave states. In lingering hepatitis, the growth of NK cytotoxicity started considerably later than in a cyclic disease. During the first 2-3 weeks of the illness, the patients with lingering hepatitis manifested the enhancement of NK suppression, particularly in conditions of medium severity and in grave states. The correlation between the clinical course of viral hepatitis and the functional activity of NK suggests that NK together with the other factors may play an important role in the pathogenesis of viral hepatitis.