Effect of human adenovirus on natural killer cell activity in mice

The influence of human adenovirus type 6 on the natural killer cell activity in mice has been investigated. The cytotoxic effect of splenic mononuclear cells of different mouse strains (Balb/c, CBA and BlO) against YAC-1 cells was estimated using a 51Cr release system assay. The effector cells responsible for cytotoxicity were identified by Percoll density gradient fractionation as LGL cells. A single intraperitoneal injection of the virus enhanced the natural killer activity in all three strains of mice. The cytotoxicity was enhanced 24 to 48 h after the virus injection, depending on the host strains, but it then decreased and the preinjection level was reached after 72 h. A good correlation was found between the augmented cytotoxicity and interferon induction.