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David J. Volsky - One of the best experts on this subject based on the ideXlab platform.

  • The macrophage response to HIV-1: Intracellular control of X4 virus replication accompanied by activation of chemokine and cytokine synthesis
    Journal of NeuroVirology, 2002
    Co-Authors: Iqbal H. Chowdhury, Mary Jane Potash, Galina Bentsman, Wonkyu Choe, David J. Volsky
    Abstract:

    During human immunodeficiency virus (HIV)-1 infection, T lymphocytes and macrophages play dual roles. They are the primary targets for virus replication, but they are also primary effector cells in acquired and innate immunity, respectively. The authors are now investigating how these roles come together in the response of human monocyte-derived macrophages (MDM) to certain HIV-1. The authors and others have previously shown that MDM permit entry of some X4 virus strains, but control viral replication intracellularly. In the present study, viral DNA synthesis, entry into the nucleus, and transcription to RNA were all observed in X4 virus-infected MDM. MDM arrested HIV-1 replication prior to expression of mature capsid Antigen P24 and production of cell-free infectious viral particles. Cell-associated transmissible HIV-1 was detected by cocultivation of infected MDM and susceptible T lymphocytes. A second protective response of MDM to specific R5 as well as X4 HIV-1 was identified in rapid and extensive secretion of tumor necrosis factor-α, macrophage inflammatory protein-1α, and RANTES. These findings support the view that MDM act aggressively to control HIV-1 replication: X4 strains by severely limiting the progeny virus production and R5 strains by producing β-chemokines competent to block virus entry into target cells. Optimizing these innate immune responses offers another means to control HIV-1 infection in the human host.

  • Prolonged Infection of Peripheral Blood Lymphocytes by Vif-Negative HIV Type 1 Induces Resistance to Productive HIV Type 1 Infection through Soluble Factors
    AIDS research and human retroviruses, 2000
    Co-Authors: Malgorzata Simm, Olga Pekarskaya, Mary Jane Potash, David J. Volsky
    Abstract:

    The auxiliary protein Vif is essential for productive HIV-1 infection of primary lymphocytes and macrophages. Vif is required for the synthesis of infectious progeny virus and infection of peripheral blood lymphocytes (PBLs) by Vif-negative HIV-1 was thought to be confined to a single cycle. Here we define conditions for the maintenance of Vif-negative HIV-1 in PBLs during multiple rounds of viral infection. PBLs were infected with Vif-negative HIV-1 and then were serially cocultivated with uninfected PBLs. As determined by measurement of viral DNA, viral burdens declined but then rebounded and reached 1 copy per 30 cells after 7 weeks of culture. Viral core Antigen P24 levels dropped and remained below detection limits after three cocultivations with no observed cytotoxicity. Viral RNA was also undetectable in cocultivated cells. The incapacitating deletion in vif was maintained during cocultivation as shown by the size of the vif amplicon. The presence of viral DNA in the absence of viral P24 RNA or pro...

S. Geier - One of the best experts on this subject based on the ideXlab platform.

  • HIV-1 and tears. Results of virus isolation and polymerase chain reaction (PCR)
    Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft, 1994
    Co-Authors: A. J. Mueller, S. Geier, L. Gürtler, V. Klauss
    Abstract:

    Beside the threat of infection via HIV-containing blood, the ophthalmologist is especially interested in the possibility of HIV infection via the tears of HIV-positive persons. In a first step, we tried to isolate HIV-1 from the peripheral blood lymphocytes (PBL) of 50 HIV-1-antibody-positive persons in different stages of disease and to detect reverse transcriptase (RT) and P24 Antigen (P24-Ag) in the supernatant. Simultaneously we carried out the same tests on tears of these patients. In 10 persons tears were collected using Schirmer strips, in 40 persons by means of microcapillaries. In a second step 10 sample pairs (PBL and tears) were tested with the polymerase chain reaction to detect proviral sequences of HIV-1 (gag, pol, env). In the first step it was not possible to isolate HIV-1 from tears, nor was it possible to detect RT or P24-Ag from the supernatant. In contrast, this was successful in 32 of the 50 examined cases for the PBL. In the second step, it was possible to detect gag, pol and env in all 10 PBL samples, while gag and pol could be detected only in one tear sample and env not at all. Our results show that the tears of HIV-positive persons contain extremely low quantities of tissue-infectious units of HIV. In addition, proviral sequences seem to occur in much lower frequency in tears than in PBL. Infection with HIV via tears therefore appears very unlikely. These findings make it possible to assign tears a place in a semiquantitative ranking of different body fluids by HIV-1 concentration.

  • Infrequent detection of HIV-1 components in tears compared to blood of HIV-1-infected persons
    Infection, 1992
    Co-Authors: A. J. Mueller, V. Klauss, S. Geier, L. Gürtler
    Abstract:

    Beside the risk of infection via HIV-1-contaminated blood, ophthalmologists are especially interested in the possibility of HIV-1 infection via tears. Therefore we tried to isolate HIV-1 from tears of 50 HIV-1-infected persons in different stages of disease by reverse transcriptase (RT) and by P24-Antigen (P24-AG) in the cultures. Simultaneously we tried to isolate HIV-1 in the supernatant from peripheral blood lymphocytes (PBL), which was successful in 32 of the 50 examined specimens. HIV-1 could not be isolated from the tears of these persons. In addition, polymerasechain-reaction (PCR) was performed to detect proviral sequences (gag, pol, env) of HIV-1 in tears and blood of ten HIV-1-infected patients. While in all the examined patients gag, pol and env could be detected in the blood samples, only one tear sample was found positive for gag and pol DNA fragments. These results indicate that tears of HIV-1-positives contain extremely low quantities of tissue culture infectious doses (TCID) of HIV-1 in contrast to PBL. HIV-1 infection via tears therefore appears to be unlikely. Neben der Infektionsgefahr durch HIV-haltiges Blut interessiert Ophthalmologen vor allem auch die Möglichkeit einer Infektion über die Tränenflüssigkeit. Wir haben deshalb versucht, HIV-1 aus der Tränenflüssigkeit von 50 HIV-1-infizierten Personen in unterschiedlichem Stadium der Erkrankung zu isolieren und über Reverse Transkriptase (RT) sowie P24-Antigen (P24-AG) im Kulturüberstand nachzuweisen. Parallel hierzu wurde aus dem Kulturüberstand peripherer Blutlymphozyten (PBL) der jeweiligen Personen eine Virusisolierung versucht. Dies gelang in 32 der 50 Fälle. Dagegen konnte in keinem Fall HIV-1 aus den Tränen der entsprechenden Personen isoliert werden. Zusätzlich wurde versucht, bei 10 HIV-1-infizierten Patienten in Tränenflüssigkeit und PBL provirale Sequenzen (gag, pol, env) von HIV-1 mittels der Polymerase-Ketten-Reaktion (PCR) nachzuweisen. Während dies in allen 10 Fällen mit PBL gelang, konnte nur in einem Fall HIV-DNA über gag- und pol-Amplifikate in der Tränenflüssigkeit nachgewiesen werden. Diese Ergebnisse sprechen für einen niedrigen Gehalt der Tränenflüssigkeit an gewebeinfektiösen Einheiten von HIV-1 im Vergleich mit dem Blut HIV-1-infizierter Personen. Damit scheint eine Infektion über den Kontakt mit Tränenflüssigkeit HIV-1-Infizierter weiter unwahrscheinlich.

  • Infrequent detection of HIV-1 components in tears compared to blood of HIV-1-infected persons.
    Infection, 1992
    Co-Authors: A. J. Mueller, V. Klauss, Lutz G. Gürtler, S. Geier
    Abstract:

    Beside the risk of infection via HIV-1-contaminated blood, ophthalmologists are especially interested in the possibility of HIV-1 infection via tears. Therefore we tried to isolate HIV-1 from tears of 50 HIV-1-infected persons in different stages of disease by reverse transcriptase (RT) and by P24-Antigen (P24-AG) in the cultures. Simultaneously we tried to isolate HIV-1 in the supernatant from peripheral blood lymphocytes (PBL), which was successful in 32 of the 50 examined specimens. HIV-1 could not be isolated from the tears of these persons. In addition, polymerasechain-reaction (PCR) was performed to detect proviral sequences (gag, pol, env) of HIV-1 in tears and blood of ten HIV-1-infected patients. While in all the examined patients gag, pol and env could be detected in the blood samples, only one tear sample was found positive for gag and pol DNA fragments. These results indicate that tears of HIV-1-positives contain extremely low quantities of tissue culture infectious doses (TCID) of HIV-1 in contrast to PBL. HIV-1 infection via tears therefore appears to be unlikely.

Hervé Fleury - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of HIV-1 expression in vivo with in situ hybridization and the polymerase chain reaction.
    Molecular and cellular probes, 1992
    Co-Authors: B. Delord, M. Ottmann, M.-h. Schrive, J.-m. Ragnaud, J.-m. Seigneurin, Hervé Fleury
    Abstract:

    Abstract The objective of the present study was to compare the data of in situ hybridization (ISH), RNA polymerase chain reaction (PCR/RNA) and P24 core Antigen (P24 Ag) enzyme immunoassay (EIA) for the detection of HIV-1 expression in peripheral blood mononuclear cells (PBMCs) and in plasma of infected patients at various CDC stages. PBMCs of 24 patients mostly of CDC stage II were obtained from heparinized blood samples, cytocentrifuged and hybridized with a ( 35 S) labelled single-stranded RNA probe specific for gag-pol of LAV Bru HIV-1 allowing the detection of genomic and/or messenger RNA. The corresponding plasma samples were used for the determination of P24 Ag by EIA and detection of HIV-1 genomic RNA by RT-PCR using specific primers in the LTR, gag and env regions. Whereas P24 was detected in only six out of 24 patients, both ISH and PCR/RNA enabled the detection of viral RNAs in more than 60% of the patients; cumulation of positive results of ISH and RT-PCR showed that 100% of patients at stage IV and 83% of patients at stages II/III have molecular signs of HIV expression therefore indicating that transcription of the provirus is a highly frequent event, even in the early stages of the disease, and, pleading for undertaking a very early antiviral chemotherapy.

  • In vitro assays show a dissociation of reverse transcriptase activity and core Antigen (P24) production in two HIV-1 isolates from a patient receiving long-term treatment with zidovudine (ZDV).
    Journal of acquired immune deficiency syndromes, 1991
    Co-Authors: Bernard Masquelier, T. Combeau, J.-d. Poveda, B. Delord, Jean-luc Pellegrin, M.-l. Sallafranque-andreola, L. Tarrago-litvak, Hervé Fleury
    Abstract:

    Two HIV-1 isolates were obtained from a patient receiving long-term treatment with zidovudine (ZDV). The in vitro sensitivity to ZDV triphosphate of the reverse transcriptase (RT) from both isolates appeared to be unchanged compared to that of the LAV-Bru HIV-1 reference strain. When isolates were grown in CEM cells (a T-lymphoblastoid tumor cell line) and their RT activity and core Antigen (P24) production were determined, the level of P24 production compared to RT activity was high; in infected CEM cells treated with ZDV, RT activity was at background level while the P24 production was still significant, thus indicating a dissociation of RT activity and core Antigen production.

A. J. Mueller - One of the best experts on this subject based on the ideXlab platform.

  • HIV-1 and tears. Results of virus isolation and polymerase chain reaction (PCR)
    Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft, 1994
    Co-Authors: A. J. Mueller, S. Geier, L. Gürtler, V. Klauss
    Abstract:

    Beside the threat of infection via HIV-containing blood, the ophthalmologist is especially interested in the possibility of HIV infection via the tears of HIV-positive persons. In a first step, we tried to isolate HIV-1 from the peripheral blood lymphocytes (PBL) of 50 HIV-1-antibody-positive persons in different stages of disease and to detect reverse transcriptase (RT) and P24 Antigen (P24-Ag) in the supernatant. Simultaneously we carried out the same tests on tears of these patients. In 10 persons tears were collected using Schirmer strips, in 40 persons by means of microcapillaries. In a second step 10 sample pairs (PBL and tears) were tested with the polymerase chain reaction to detect proviral sequences of HIV-1 (gag, pol, env). In the first step it was not possible to isolate HIV-1 from tears, nor was it possible to detect RT or P24-Ag from the supernatant. In contrast, this was successful in 32 of the 50 examined cases for the PBL. In the second step, it was possible to detect gag, pol and env in all 10 PBL samples, while gag and pol could be detected only in one tear sample and env not at all. Our results show that the tears of HIV-positive persons contain extremely low quantities of tissue-infectious units of HIV. In addition, proviral sequences seem to occur in much lower frequency in tears than in PBL. Infection with HIV via tears therefore appears very unlikely. These findings make it possible to assign tears a place in a semiquantitative ranking of different body fluids by HIV-1 concentration.

  • Infrequent detection of HIV-1 components in tears compared to blood of HIV-1-infected persons
    Infection, 1992
    Co-Authors: A. J. Mueller, V. Klauss, S. Geier, L. Gürtler
    Abstract:

    Beside the risk of infection via HIV-1-contaminated blood, ophthalmologists are especially interested in the possibility of HIV-1 infection via tears. Therefore we tried to isolate HIV-1 from tears of 50 HIV-1-infected persons in different stages of disease by reverse transcriptase (RT) and by P24-Antigen (P24-AG) in the cultures. Simultaneously we tried to isolate HIV-1 in the supernatant from peripheral blood lymphocytes (PBL), which was successful in 32 of the 50 examined specimens. HIV-1 could not be isolated from the tears of these persons. In addition, polymerasechain-reaction (PCR) was performed to detect proviral sequences (gag, pol, env) of HIV-1 in tears and blood of ten HIV-1-infected patients. While in all the examined patients gag, pol and env could be detected in the blood samples, only one tear sample was found positive for gag and pol DNA fragments. These results indicate that tears of HIV-1-positives contain extremely low quantities of tissue culture infectious doses (TCID) of HIV-1 in contrast to PBL. HIV-1 infection via tears therefore appears to be unlikely. Neben der Infektionsgefahr durch HIV-haltiges Blut interessiert Ophthalmologen vor allem auch die Möglichkeit einer Infektion über die Tränenflüssigkeit. Wir haben deshalb versucht, HIV-1 aus der Tränenflüssigkeit von 50 HIV-1-infizierten Personen in unterschiedlichem Stadium der Erkrankung zu isolieren und über Reverse Transkriptase (RT) sowie P24-Antigen (P24-AG) im Kulturüberstand nachzuweisen. Parallel hierzu wurde aus dem Kulturüberstand peripherer Blutlymphozyten (PBL) der jeweiligen Personen eine Virusisolierung versucht. Dies gelang in 32 der 50 Fälle. Dagegen konnte in keinem Fall HIV-1 aus den Tränen der entsprechenden Personen isoliert werden. Zusätzlich wurde versucht, bei 10 HIV-1-infizierten Patienten in Tränenflüssigkeit und PBL provirale Sequenzen (gag, pol, env) von HIV-1 mittels der Polymerase-Ketten-Reaktion (PCR) nachzuweisen. Während dies in allen 10 Fällen mit PBL gelang, konnte nur in einem Fall HIV-DNA über gag- und pol-Amplifikate in der Tränenflüssigkeit nachgewiesen werden. Diese Ergebnisse sprechen für einen niedrigen Gehalt der Tränenflüssigkeit an gewebeinfektiösen Einheiten von HIV-1 im Vergleich mit dem Blut HIV-1-infizierter Personen. Damit scheint eine Infektion über den Kontakt mit Tränenflüssigkeit HIV-1-Infizierter weiter unwahrscheinlich.

  • Infrequent detection of HIV-1 components in tears compared to blood of HIV-1-infected persons.
    Infection, 1992
    Co-Authors: A. J. Mueller, V. Klauss, Lutz G. Gürtler, S. Geier
    Abstract:

    Beside the risk of infection via HIV-1-contaminated blood, ophthalmologists are especially interested in the possibility of HIV-1 infection via tears. Therefore we tried to isolate HIV-1 from tears of 50 HIV-1-infected persons in different stages of disease by reverse transcriptase (RT) and by P24-Antigen (P24-AG) in the cultures. Simultaneously we tried to isolate HIV-1 in the supernatant from peripheral blood lymphocytes (PBL), which was successful in 32 of the 50 examined specimens. HIV-1 could not be isolated from the tears of these persons. In addition, polymerasechain-reaction (PCR) was performed to detect proviral sequences (gag, pol, env) of HIV-1 in tears and blood of ten HIV-1-infected patients. While in all the examined patients gag, pol and env could be detected in the blood samples, only one tear sample was found positive for gag and pol DNA fragments. These results indicate that tears of HIV-1-positives contain extremely low quantities of tissue culture infectious doses (TCID) of HIV-1 in contrast to PBL. HIV-1 infection via tears therefore appears to be unlikely.

Ramon Cisterna - One of the best experts on this subject based on the ideXlab platform.

  • Correlative Detection of Human Immunodeficiency Virus (HIV) Antigen P24 and Epstein-Barr Virus DNA In Vitro : Clinical Influence on HIV Infection
    Microbiology and Immunology, 1992
    Co-Authors: Pilar Lardelli, Diego Manzano, Antón I, Lucila Madariaga, Seth M Steinberg, Ramon Cisterna
    Abstract:

    The existence of molecular transactivations between EBV and HIV-1, as well as reactivations of EBV latent infections in AIDS patients, have been recently documented. In order to shed more light on the putative association between EBV and HIV, and its role in the evolution to AIDS, we have determined simultaneously P24 protein and EBV DNA in culture supernatants of peripheral blood mononuclear cells from 47 individuals suspected of having HIV infection. The results of the in vitro assays were correlated with the clinical stage of the individuals and their serologic status to EBV. Statistical analysis showed a concordance between HIV infection and in vitro detection of EBV DNA (P < 0.002); particularly, a strong correlation between the presence of EBV DNA and P24 in culture was observed (P < 0.001). These results are consistent with the occurrence of viral interactions, manifested in vitro. However, in our series, the appearance of EBV DNA in culture was not concomitant with an elevation of anti-VCA IgG titers, anti-EA titers or the development of symptomatology, suggestive of a reactivation of a latent EBV infection or a progression of HIV infection. Therefore we conclude that, although interaction between both viruses may take place at the molecular level, there is no clear evidence of the repercussion that this event may have on the clinical course of HIV infection.

  • Evidence of an in vitro association between human immunodeficiency virus Antigen P24 and Epstein-Barr virus DNA
    European Journal of Clinical Microbiology and Infectious Diseases, 1992
    Co-Authors: Pilar Lardelli, Seth M Steinberg, C. Campelo, A. F. Aranguiz, L. Sarría, M. T. Gorriño, Ramon Cisterna
    Abstract:

    To investigate the association between human immunodeficiency virus (HIV) and Epstein-Barr virus (EBV), simultaneous determinations of HIV Antigen (HIV Ag) P24 and EBV DNA were performed in lymphocyte culture supernatants from 63 individuals at risk of HIV infection. In vitro data, together with HIV immune status results, were subjected to a statistical analysis. HIV infection was identified in 49 patients (78 %); of these, in vitro EBV DNA was found in 44 individuals (90 %), while in only 3 of the 14 non-infected ones (21 %). Statistical analysis demonstrated a close relationship between evidence of HIV infection and in vitro detection of EBV DNA (87.3 % concordant with 95 % confidence interval: 76.5 %–94.5 %). Furthermore, a strong dependence was revealed between the presence of EBV DNA and HIV Ag in culture (p