Viral DNA In Liver Research Articles

In vitro and in vivo biology of recombinant adenovirus vectors with E1, E1/E2A, or E1/E4 deleted.

Isogenic, E3-deleted adenovirus vectors defective in E1, E1 and E2A, or E1 and E4 were generated in complementation cell lines expressing E1, E1 and E2A, or E1 and E4 and characterized in vitro and in vivo. In the absence of complementation, deletion of both E1 and E2A completely abolished expression of early and late viral genes, while deletion of E1 and E4 impaired expression of viral genes, although at a lower level than the E1/E2A deletion. The in vivo persistence of these three types of vectors was monitored in selected strains of mice with viral genomes devoid of transgenes to exclude any interference by immunogenic transgene-encoded products. Our studies showed no significant differences among the vectors in the short-term maintenance and long-term (4-month) persistence of viral DNA in liver and lung cells of immunocompetent and immunodeficient mice. Furthermore, all vectors induced similar antibody responses and comparable levels of adenovirus-specific cytotoxic T lymphocytes. These results suggest that in the absence of transgenes, the progressive deletion of the adenovirus genome does not extend the in vivo persistence of the transduced cells and does not reduce the antivirus immune response. In addition, our data confirm that, in the absence of transgene expression, mouse cellular immunity to viral antigens plays a minor role in the progressive elimination of the virus genome.

Hepatitis B viral DNA in liver and serum of asymptomatic carriers

Hepatitis B viral DNA in liver and serum of asymptomatic carriers

Hepatitis B viral DNA in liver and serum of asymptomatic carriers.

Cloned DNA probes were used to test for hepatitis B virus (HBV) DNA in the liver and serum of 14 asymptomatic hepatitis B surface antigen (HBsAg) carriers and two former carriers. The results were compared with serological markers of HBV infection and liver histopathology. Three groups of carriers were distinguished. In group I, HBV DNA was present in both liver and serum. Hepatitis B e antigen (HBeAg), a marker of viral replication, was uniformly positive in serum. In one individual in this group, viral DNA was also integrated into liver genomic DNA. In group II, lower levels of nonintegrated HBV DNA were detected in the liver, but no HBV DNA was found in the serum. HBeAg was negative and with one exception there were antibodies to HBeAg. Integrated viral DNA was present in each case. In group III, there was no detectable nonintegrated viral DNA in serum or liver, but one individual had integrated sequences. All carriers lacked antibodies to HBsAg and had antibodies to hepatitis B core antigen and demonstrated nonspecific histological abnormalities in the liver. These findings indicate significant quantitative and qualitative differences among asymptomatic HBsAg carriers and suggest that their infectivity may be highly variable.