Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ADENOVIRUS INFECTIONS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 559 records · Page 31Linked to original sources
PubMed1985

Increase in DNA polymerase alpha in nuclei of chicken kidney cells after avian adenovirus infection.

DNA polymerase activity which sedimented at about 7s in the presence of 0.5M KC1 increased in cultured kidney cells after infection with a chicken embryo lethal orphan virus, an avian adenovirus. Elevated levels of antigenic material to a monoclonal antibody specific for the large subunit of chicken DNA polymerase alpha were also detected in nuclei of virus-infected cells by an immunofluorescence method. Since the elevations of DNA polymerase activity and of nuclear immunofluorescence was not inhibited with 1-beta-D-arabinofuranosylcytosine, the early viral gene(s) seems to be responsible for the induction of the synthesis and nuclear accumulation of DNA polymerase alpha.

Adenoviridae Infections↗
PubMed1989

E2F from adenovirus-infected cells binds cooperatively to DNA containing two properly oriented and spaced recognition sites.

E2F is a sequence-specific DNA-binding factor which binds to sites that occur in pairs upstream of the adenovirus E1A and E2 early transcriptional start sites. Substantial quantities of E2F activity were found in uninfected-cell extracts, and there was a modest increase in E2F activity during an adenovirus type 5 (Ad5) infection. In uninfected cells, E2F was found to exist in multiple forms that could be separated chromatographically. Extracts prepared at 24 h after Ad5 infection contained a new form of E2F. This infection-specific form may have been a modified version of one of the forms present in uninfected cells. The infection-specific E2F was shown to bind cooperatively to a pair of E2F sites found upstream of the Ad2 early region 2 mRNA cap site. This binding was sensitive to the spacing between the sites and their relative orientation. In contrast, E2F binding in uninfected-cell extracts was unaffected by changes in orientation and spacing, consistent with very low cooperativity or independent binding.

Adenovirus Early Proteins↗
PubMed1992

Effects of fowl adenovirus infection on the immune system of chickens.

A virulent strain of serotype 8 fowl adenovirus (FAV) was isolated from an outbreak of inclusion body hepatitis (IBH) in broiler flocks. Post-mortem changes included characteristic liver lesions with intranuclear inclusion bodies in the hepatocytes and severe lymphocytic depletion in the bursa, thymus and spleen. The packed cell volume was reduced by 50 per cent or more and varying amounts of cell depletion were observed in the bone marrow. Typical IBH was reproduced in specific pathogen-free chickens inoculated orally with the FAV isolated from the natural infection. There was severe depletion of lymphocytes in the bursa, thymus and spleen of the experimentally infected birds and FAV antigens were detected by ELISA and immunocytochemical staining in various lymphoid tissues. Humoral antibody responses against sheep red blood cells, detected by the haemagglutination test, were decreased in the chickens infected with FAV. These findings suggest that the damage caused by replication of this virulent strain of FAV in lymphoid tissues compromises the immunological capabilities of infected chickens.

Adenoviridae Infections↗
PubMed1981

Protein kinase activity immunoprecipitated from adenovirus infected cells by sera from tumor-bearing hamsters.

Earlier, we reported (N. J. Lassam, S. T. Bayley, F. L. Graham, and P. E. Branton, Nature (London) 277:241-243, 1979) detecting protein kinase activity when cytoplasmic extracts of human adenovirus type 5 (Ad5)-infected KB cells immunoprecipitated with 14b antitumor serum directed against the transforming proteins of Ad5, were incubated with [gamma-32P]ATP. Here we show that in the in vitro assay this kinase phosphorylated both the heavy chain of immunoglobulin G and polypeptide than comigrated on sodium dodecyl sulfate gels with the 58,000-dalton Ad5 antigen. It also phosphorylated added histone H3. Evidence is presented that the protein kinase activity found with extracts from Ad5-infected cells is not due to nonspecific trapping of cellular enzymes in immune complexes, but to an enzyme which is distinct from kinases detected at background levels in controls. Serine and threonine were the major phosphorylated amino acids, and essentially no phosphotyrosine was detected. Protein kinase activity detected in Ad12-infected cells immunoprecipitated by an antiserum derived from hamsters bearing Ad12-induced tumors appeared to be immunologically distinct from that immunoprecipitated from Ad5-infected cells by 14b serum.

Adenoviruses, Human↗
PubMed2005

Substrate-dependent differences in U2AF requirement for splicing in adenovirus-infected cell extracts.

U2AF has been characterized as an essential splicing factor required for efficient recruitment of U2 small nuclear ribonucleoprotein to the 3'-splice site in a pre-mRNA. The U2AF65 subunit binds to the pyrimidine tract of the pre-mRNA, whereas the U2AF(35) subunit contacts the 3'-splice site AG. Here we show that U2AF35 appears to be completely dispensable for splicing in nuclear extracts prepared from adenovirus late-infected cells (Ad-NE). As a consequence, the viral IIIa and cellular IgM introns, which both have suboptimal 3'-splice sites and require U2AF35 for splicing in nuclear extracts from uninfected cells, are transformed to U2AF35-independent introns in Ad-NE. Furthermore, we present evidence that two parallel pathways of 3'-splice site recognition exist in Ad-NE. We show that the viral 52,55K intron, which has an extended pyrimidine tract, requires U2AF for activity in Ad-NE. In contrast, the IgM intron, which has a weak 3'-splice site sequence context, undergoes the first catalytic step of splicing in U2AF-depleted Ad-NE, suggesting that spliceosome assembly occurs through a novel U2AF-independent pathway in Ad-NE.

Adenoviridae↗
PubMed2002

Adenovirus infection induces microglial activation: involvement of mitogen-activated protein kinase pathways.

Non-replicating adenovirus vectors (AdV) represent effective tools for long-term gene expression in the central nervous system (CNS), but they also elicit inflammation. The cellular and molecular mechanisms of such a response are not understood. In the present study, we show that infection with AdV causes activation of microglial cells, the key cells involved in inflammatory and immune-regulatory functions in the brain. Exposure of cultured rat brain microglia to AdV resulted in an induced production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS) and the pro-inflammatory cytokine, TNFalpha. The roles of signal transduction pathways believed to be involved in microglial activation in particular, mitogen-activated protein kinases (MAPKs) and nuclear factor kappaB (NFkappaB) were explored by determining their activation in response to AdV infection and by testing the effects of specific pharmacological inhibitors. It was found that AdV strongly activates extracellular signal-regulated kinase (ERK) and to a lesser extent, p38 MAPK but not NFkappaB. Addition of the kinase inhibitor, i.e. PD98059 (specific for the ERK pathway), inhibits and, in combination with the p38 MAPK inhibitor, SB203580, drastically suppresses AdV-induced expression of iNOS and TNFalpha. The results suggest that AdV uses cellular signal transduction machinery, in particular the MAPK pathways, to elicit microglial activation and that increased production by these cells of inflammatory mediators may primarily contribute to CNS inflammatory responses commonly seen in models of gene therapy using AdV vectors.

Adenoviridae Infections↗