44 research outputs found

    Truncated forms of human and simian immunodeficiency virus in infected individuals and rhesus macaques are unique or rare quasispecies

    Get PDF
    AbstractTruncated proviruses of variable sizes are present in peripheral blood mononuclear cells (PBMC) of human immunodeficiency virus type 1 (HIV-1)-infected persons and simian immunodeficiency virus (SIV)-infected rhesus macaques. Here, we investigated whether the highly deleted HIV and SIV proviruses are present in infected organisms as multiple copies or whether each truncated provirus is unique. Using end-point dilution, multiple long-distance (LD) DNA PCR assays were run in parallel using DNA extracted from PBMC of seropositive, treatment-naive persons and from lymph nodes of a rhesus monkey inoculated with cloned, full-length SIVmac239 DNA. The PCR products were titrated and mapped. Most truncated proviruses were present in the DNA samples tested as single, nonintegrated molecules that differed from one another in size and/or nucleotide sequence. These results indicate that truncated primate lentiviral sequences found in infected tissues are unique or rare quasispecies that do not replicate significantly

    Acute Schistosoma mansoni Infection Increases Susceptibility to Systemic SHIV Clade C Infection in Rhesus Macaques after Mucosal Virus Exposure

    Get PDF
    To test the hypothesis that infection with helmiths may increase host susceptibility to infection with HIV-1, we quantified the amount of a clade C simian-human immunodeficiency virus needed to infect rhesus macaques that had acute Schistosoma mansoni infections. Compared to control animals exposed to virus alone, monkeys with schistosomiasis required exposure to 17-fold lower levels of virus to become infected. The schistosome-infected monkeys also had significantly higher levels of initial virus replication and loss of a certain subset of memory T cells, both predictors of a more rapid progression to immune dysfunction. These results suggest that worm infections may increase the risk of becoming infected with HIV-1 among individuals with viral exposures. Furthermore, they support the idea that control programs for schistosomiasis and perhaps other parasitic worm infections may also be useful in helping to reduce the spread of HIV/AIDS in developing countries where helminths are endemic

    Etude de l'infection de l'épithélium intestinal par VIH-1

    No full text
    AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocPARIS-BIUM (751062103) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF

    Long-Term Productive Human Immunodeficiency Virus Infection of CD1a-Sorted Myeloid Dendritic Cells

    No full text
    Myeloid, CD1a-sorted dendritic cells (MDC) productively replicated human immunodeficiency virus strains encoding envelope genes of either primary X4R5 or R5 strains for up to 45 days. Cell-free supernatant collected from long-term infected MDC, which had been exposed to an X4R5 virus 45 days earlier, was still infectious when placed over activated T cells. These data imply that DC can act as a persistent reservoir of infectious virus

    Older Rhesus Macaque Infants Are More Susceptible to Oral Infection with Simian-Human Immunodeficiency Virus 89.6P than Neonates

    No full text
    Earlier primate studies revealed that oral transmission of immunodeficiency viruses can occur at all ages [R. M. Ruprecht et al., J. Infect. Dis. 179(Suppl. 3):S408-S412, 1999]. Using a stock of pathogenic simian-human immunodeficiency virus, SHIV89.6P, we compared the 50% animal infectious dose needed to achieve systemic infection after oral challenge in newborn and older infant or juvenile rhesus macaques. Unexpectedly, the older monkeys required a 150-fold-lower virus challenge dose than the neonates (P = 3.3 × 10(−5)). In addition, at least 60,000 times more virus was needed to achieve systemic infection in neonates by the oral route than by the intravenous route (P < 1 × 10(−5)). Thus, route of inoculation and age are important determinants of SHIV89.6P infectivity in rhesus macaques

    Extensively deleted simian immunodeficiency virus (SIV) DNA in macaques inoculated with supercoiled plasmid DNA encoding full-length SIVmac239

    Get PDF
    Using long-distance DNA PCR, we prospectively followed rhesus monkeys that had been inoculated intramuscularly with supercoiled plasmid DNA encoding intact simian immunodeficiency virus (SIV). From 4 to 10 weeks postinoculation onward, we detected extensively deleted proviral genomes along with full-length viral genomes in peripheral blood mononuclear cells (PBMC) in adult macaques. During their chronic asymptomatic phase of infection, the frequency of deleted proviral genomes was similar in PBMC and lymph nodes. The latter, however, harbored significantly more full-length proviral DNA than PBMC, consistent with the lack of effective antiviral cytotoxic T-cell activity in lymph nodes described by others during human immunodeficiency virus infection. After the macaques progressed to AIDS, full-length proviral DNA became equally abundant in lymph nodes and in PBMC. We have demonstrated that although a single molecular species of proviral DNA was inoculated, genomic diversity was detected within a short time, thus confirming the genetic instability of the SIV genome in vivo

    Live attenuated, nef-deleted SIV is pathogenic in most adult macaques after prolonged observation

    Full text link
    OBJECTIVE: A live attenuated SIV vaccine strain, termed SIVmac239Delta3 and containing large deletions in, and the negative regulatory element, was previously shown to cause AIDS mostly in monkeys vaccinated as infants. In the present study, we demonstrate that SIVmac239Delta3 is pathogenic in most vaccinated adult monkeys, given enough time. METHODS: Eleven rhesus macaques vaccinated as adults with SIVmac239Delta3 were followed for extended periods (up to 6.8 years). RESULTS: We found signs of immune dysregulation in all 11 adult vaccinees. All animals developed persistently inverted CD4 : CD8 T-cell ratios, seven (64%) had persistent recurrent viremia, and six (55%) had decreased CD4 T-cell counts ( or = 10 copies/ml and cytoviremia was a poor prognostic sign. CONCLUSION: Our data demonstrate that with time, a live attenuated, multiply deleted SIV vaccine can cause immune dysregulation in most vaccine recipients, even in initially immune competent, healthy adults. Immune dysfunction can progress to full AIDS. However, pathogenic effects became evident only several years after vaccination. Thus, mass vaccination of humans with similarly constructed live attenuated HIV vaccines, recently suggested for countries with high HIV-1 transmission rates, seems contraindicated

    Infectious Molecular Clone of a Recently Transmitted Pediatric Human Immunodeficiency Virus Clade C Isolate from Africa: Evidence of Intraclade Recombination

    Get PDF
    Although human immunodeficiency virus type 1 (HIV-1) clade C continues to dominate the pandemic, only two infectious clade C proviral DNA clones have been described (N. Mochizuki, N. Otsuka, K. Matsuo, T. Shiino, A. Kojima, T. Kurata, K. Sakai, N. Yamamoto, S. Isomura, T. N. Dhole, Y. Takebe, M. Matsuda, and M. Tatsumi, AIDS Res. Hum. Retrovir. 15:1321-1324, 1999; T. Ndung'u, B. Renjifo, and M. Essex, J. Virol. 75:4964-4972, 2001). We have generated an infectious molecular clone of a pediatric clade C strain, HIV1084i, which was isolated from a Zambian infant infected either intrapartum or through breastfeeding. HIV1084i is an R5, non-syncytium-inducing isolate that bears all known clade C signatures; gag, pol, and env consistently mapped within clade C. Interestingly, gag resembled Asian isolates, whereas pol and env resembled African isolates, indicating that HIV1084i probably arose from an intraclade recombination. As a recently transmitted clade C strain, HIV1084i will be a useful vaccine development tool

    Quantitation of Simian Cytokine andβ-Chemokine mRNAs, using real-time reverse transcriptase-polymerase chain reaction: variations in expression during chronic primate lentivirus infection

    Full text link
    Cytokines and β-chemokines are important mediators of the immune system and are expressed in many infectious diseases. To study cytokine and β-chemokine profiles during pathogenesis of lentiviral infection and progression to AIDS in rhesus macaques, we established new quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assays based on TaqMan chemistry. Using synthetic RNA standards, we quantified mRNAs of IL-2, IL-4, IL-6, IL-10, IL-12 p40, interferon γ (IFN-γ), tumor necrosis factor α (TNF-α), RANTES, macrophage inflammatory protein 1α (MIP-1α), and MIP-1β in unstimulated peripheral blood mononuclear cells (PBMCs) and lymph nodes from macaques chronically infected with SIV or SHIV. Viremic monkeys with decreased CD4+ T cell counts (<500 cells/μl) had significantly higher IL-10 mRNA expression than uninfected controls, which parallels the findings in HIV-1-infected humans. In addition, MIP-1α, MIP-1β, and RANTES mRNA expression increased in viremic monkeys with decreased CD4+ T cell counts; gene expression was inversely correlated with CD4+ T cell counts, but not viral load. The newly established quantitative real-time RT-PCR assays will allow the determination of cytokine and β-chemokine patterns in rhesus macaques in studies of microbial pathogenesis or vaccine development

    Molecular Evolution of Human Immunodeficiency Virus env in Humans and Monkeys: Similar Patterns Occur during Natural Disease Progression or Rapid Virus Passage

    Get PDF
    Neonatal rhesus macaque 95-3 was inoculated with nonpassaged simian-human immunodeficiency virus strain SHIV-vpu(+), which encodes env of the laboratory-adapted human immunodeficiency virus (HIV) strain IIIB and is considered nonpathogenic. CD4(+) T-cell counts dropped to <200 cells/μl within 4.6 years, and monkey 95-3 died with opportunistic infections 5.9 years postinoculation. Transfer of blood from 95-3 to two naive adult macaques resulted in high peak viral loads and rapid, persistent T-cell depletion. Progeny virus evolved in 95-3 despite high SHIV-vpu(+) neutralizing antibody titers and still used CXCR4 but, in contrast to parental SHIV-vpu(+), productively infected macrophages and resisted neutralization. Sequence analysis revealed three new potential glycosylation sites in gp120; another two were lost. Strikingly similar mutations were detected in a laboratory worker who progressed to AIDS after accidental HIV-IIIB infection (T. Beaumont et al., J. Virol. 75:2246-2252, 2001), thus supporting the SHIV-vpu(+)/rhesus macaque system as a relevant model. Similar mutations were also described after rapid passage of chimeric viruses encoding IIIB env in rhesus and pig-tailed macaques (M. Cayabyab et al., J. Virol. 73:976-984, 1999; Z. Q. Liu et al., Virology 260:295-307, 1999; S. V. Narayan et al., Virology 256:54-63, 1999; R. Raghavan et al., Brain Pathol. 7:851-861, 1997; E. B. Stephens et al., Virology 231:313-321, 1997). Thus, HIV-IIIB env evolved similarly in three different species; this selection occurred in chronically infected individuals during disease progression as well as after rapid virus passage. We postulate that evolutionary pressure led to the outgrowth of more aggressive viral variants in all three species
    corecore