Study on the Natural History of Hepatitis B Virus-infected Rats, and its Relationship with Chemical and Physical Injury of the Liver

ABSTRACT

Normal, hepatectomied(partial) or CCI4 injected rats are infected intraperitoneally with human HBV-infected serum, and histopathological examination of major organs, and serologically HBV markers are checked. In the latter groups, the relationship between the regenerating hepatocytes and their infectivity toward HBV are investigated. 1) There are no specific histological changes in the liver which might suggest HBV infection of hepatocytes. 2) There is a tendency to increase basophilic mononuclear cells in the lymphoid organs. At the same time, HBcAb are positive in the rat's serum suggesting that these cells are immunologically oriented effector cells in the defense system. In the groups which received hepatic injury, the number of these cells are decreased. 3) HBcAb are positive in the groups of 5th day, 1 week, and 2 weeks' post-HBV injection. All groups with hepatic injury show trace in the 2 weeks post-HBV injection which corresponds to the concomitant decreased number of basophilic mononuclear cells in the lymphoid organs. 4) Above findings suggest that HBV will promote a proliferative reaction of the mononuclear cells in the lymphoid organs in the early stage of HBV infection. It appears that the infection stops there, and there would be no activation of the mechanism of antibody-dependent cellular cytotoxicity followed by injury of hepatocytes due to the attack of T-lymphocytes manifesting the clinical hepatitis.