Establishment of infection by spleen necrosis virus: inhibition in stationary cells and the role of secondary infection

Chen, I S; Temin, Howard M.

doi:10.1128/jvi.41.1.183-191.1982

Cited by 44 publications

(17 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This value is in the same range of copy numbers determined previously for simian foamy virus type 3-infected cells (36). However, it is 10 to 100 times more than the amounts of unintegrated DNA reported for other retroviruses of avian, feline, and human origins (5,16,27,43).…”

Section: Resultssupporting

confidence: 79%

Human foamy virus reverse transcription that occurs late in the viral replication cycle

Moebes

Enssle

Bieniasz

et al. 1997

J Virol

146

View full text Add to dashboard Cite

Foamy viruses (FVs) are retroid viruses which use a replication strategy unlike those of other retroviruses and hepadnaviruses (S. F. Yu, D. N. Baldwin, S. R. Gwynn, S. Yendapilli, and M. L. Linial, Science 271:1579-1582, 1996). One of the striking differences between FVs and retroviruses is the presence of large amounts of linear genome-length DNA in FV-infected cells and in virions. We report here that large quantities of genome-length linear FV DNA accumulate in cells infected with FV, as determined by Southern blotting. To determine whether these unintegrated virus DNAs result solely from superinfection, we analyzed the occurrence of virus cDNA of the so-called human FV isolate (HFV) in cells transfected with a virus mutant deficient in the envelope gene and in cells which are resistant to superinfection due to stable expression of the envelope protein. We show that the synthesis of viral cDNA is independent of superinfection and that HFV synthesizes cDNA intracellularly as a late event in the replication cycle. To further confirm this finding, we performed inhibition studies with the reverse transcriptase inhibitor zidovudine (AZT). While AZT had no effect or only a minor effect on virus titers when added to cells prior to virus infection, viral titers were reduced by 3 or 4 orders of magnitude when the virus was produced from cells in the presence of AZT. Our results are most compatible with the hypothesis that the functional nucleic acid of the extracellular HFV consists of largely double-stranded linear DNA.

show abstract

Section: Resultssupporting

confidence: 79%

Human foamy virus reverse transcription that occurs late in the viral replication cycle

Moebes

Enssle

Bieniasz

et al. 1997

J Virol

146

View full text Add to dashboard Cite

show abstract

“…Multiple copies of unintegrated proviral DNA per cell have been demonstrated in tissue culture infections with cytopathic animal retroviruses. Examples include equine infectious anemia virus [Rasty et al, 1990], visna virus [Brahic et al, 1981], feline leukemia virus [Mullins et al, 1986], spleen necrosis virus [Chen and Temin, 1982], avian leukosis virus [Weller and Temin, 1981], and reticuloendotheliosis virus [Temin et al, 1980]. Similarly, unintegrated human immunodeficiency virus type-1 (HIV-1) proviral DNA has been demonstrated in acute in vitro infections of lymphocytes [Pauza et al, 1990;Robinson and Zinkus, 1990], monocytes [Besansky et al, 1991], and chronically infected cell lines [Chowdhury et al, 1992].…”

Section: Introductionmentioning

confidence: 99%

Unintegrated HIV-1 circular 2-LTR proviral DNA as a marker of recently infected cells: Relative effect of recombinant CD4, zidovudine, and saquinavir in vitro

Panther¹,

Coombs²,

Aung³

et al. 1999

J. Med. Virol.

View full text Add to dashboard Cite

Unintegrated HIV-1 proviral DNA is one of the earliest detectable forms of HIV-1, and the influence of an antiretroviral drug on its appearance may reflect the efficacy of that agent in preventing infection of new cells. We characterized the dynamics of HIV-1 p24 (p24) antigen production, HIV-1 gag DNA, tandem long-terminal-repeat circular unintegrated proviral (2-LTR) HIV-1 DNA, HIV-1 tat mRNA, and cell viability in the presence of three antiretroviral agents: recombinant soluble CD4 (rsCD4), zidovudine, and saquinavir. Interference with HIV-1 entry by rsCD4 decreased p24 antigen levels modestly, decreased HIV-1 gag by twofold, and 2-LTR was detectable at the end of the culture period. Inhibition of reverse transcription by zidovudine decreased p24 antigen levels modestly, decreased HIV-1 gag by 19-fold, and inhibited detection of 2-LTR HIV-1 DNA. The protease inhibitor, saquinavir, had the greatest overall effect, with the lowest levels of p24 antigen and HIV-1 gag, and inhibition of 2-LTR. There was no detection of tat mRNA in the saquinavir-treated cultures. In addition, cell viability was significantly higher in cultures treated with saquinavir. In these experiments, 2-LTR HIV-1 DNA was indicative of the relative inhibitory effects of three antiretroviral agents acting at different steps of the HIV-1 replication cycle. We demonstrated in vitro that 2-LTR HIV-1 DNA was a useful indicator of an antiretroviral drug in preventing new cell infection and could be utilized as a dynamic marker of drug efficacy in HIV-1-infected patients.

show abstract

“…Recombinant retroviruses are currently the vehicle of choice for the transfer of genes into mammalian cells (Anderson, 1992;Crystal, 1995;Hodgson, 1995;Miller, 1992;Mulligan, 1993). It is generally believed that cell division is a requirement for successful replication of oncoretroviruses (Bukrinsky et al, 1992;Chen and Temin, 1982;Fritsch and Temin, 1977;Harel, 1981;Roe et al, 1993;Springett et al, 1989;Varmus et al, 1977;Yoshikura, 1970), but not of lentiviruses such as HIV-1 (Bukrinsky et al, 1992;Lewis and Emerman, 1994). Studies with replication-defective retrovirus have shown that gene transfer was inhibited 100-fold in nonreplicating (confluent) vs. replicating cells (Miller et al, 1990).…”

Section: Introductionmentioning

confidence: 99%

Cell cycle dependence of retroviral transduction: An issue of overlapping time scales

Andreadis

Fuller

Palsson

1998

Biotechnol. Bioeng.

View full text Add to dashboard Cite

Recombinant retroviruses are currently used as gene delivery vehicles for the purpose of gene therapy. It is generally believed that the efficiency of retroviral transduction depends on the cell cycle status of the target cells. However, it has been reported that this is not the case for the transduction of human and murine fibroblasts, in contrast to other cell types such as lymphocytes. The predictions of a mathematical model that we constructed, offer an explanation of this contradiction, based on the dynamics of the underlying processes of target cell growth and the intracellular decay of retroviral vectors. The model suggests that the utility of synchronization experiments, that are usually employed to study cell cycle specificity, is severely limited when the time scales of the above kinetic events are comparable to each other. The predictions of the model also suggest the use of retroviral vectors as cell cycle markers, as an alternative way to detect cell cycle dependence of retroviral transduction. This method obviates the need for cell synchronization and therefore, it does not perturb the cell cycle or interfere with the life cycle of retroviral vectors. Moreover, it does not depend on the intracellular stability of retroviral vectors. Our results show that in contrast to previously reported results, transduction of murine fibroblasts is cell cycle dependent, and they are consistent with the current notion that mitosis is the phase that confers transduction susceptibility. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 58:272–281, 1998.

show abstract

Establishment of infection by spleen necrosis virus: inhibition in stationary cells and the role of secondary infection

Abstract: investigated by studying the kinetics of synthesis of viral DNA after secondary infection. MATERIALS AND METHODS Cells and virus. The general sources and procedures for obtaining and propagating avian fibroblast cells have been previously described (21).

Cited by 44 publications

References 26 publications

Human foamy virus reverse transcription that occurs late in the viral replication cycle

Human foamy virus reverse transcription that occurs late in the viral replication cycle

Unintegrated HIV-1 circular 2-LTR proviral DNA as a marker of recently infected cells: Relative effect of recombinant CD4, zidovudine, and saquinavir in vitro

Cell cycle dependence of retroviral transduction: An issue of overlapping time scales

Contact Info

Product

Resources

About