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Grivel JC, Shattock RJ, Margolis LB. Selective transmission of R5 HIV-1 variants: where is the gatekeeper? J Transl Med 2011; 9 Suppl 1:S6. [PMID: 21284905 PMCID: PMC3105506 DOI: 10.1186/1479-5876-9-s1-s6] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
To enter target cells HIV-1 uses CD4 and a coreceptor. In vivo the coreceptor function is provided either by CCR5 (for R5) or CXCR4 (for X4 HIV-1). Although both R5 and X4 HIV-1 variants are present in body fluids (semen, blood, cervicovaginal and rectal secretions), R5 HIV-1 appears to transmit infection and dominates early stages of HIV disease. Moreover, recent sequence analysis of virus in acute infection shows that, in the majority of cases of transmission, infection is initiated by a single virus. Therefore, the existence of a "gatekeeper" that selects R5 over X4 HIV-1 and that operates among R5 HIV-1 variants has been suggested. In the present review we consider various routes of HIV-transmission and discuss potential gatekeeping mechanisms associated with each of these routes. Although many mechanisms have been identified none of them explains the almost perfect selection of R5 over X4 in HIV-1 transmission. We suggest that instead of one strong gatekeeper there are multiple functional gatekeepers and that their superimposition is sufficient to protect against X4 HIV-1 infection and potentially select among R5 HIV-1 variants. In conclusion, we propose that the principle of multiple barriers is more general and not restricted to protection against X4 HIV-1 but rather can be applied to other phenomena when one factor has a selective advantage over the other(s). In the case of gatekeepers for HIV-1 transmission, the task is to identify them and to decipher their molecular mechanisms. Knowledge of the gatekeepers' localization and function may enable us to enhance existing barriers against R5 transmission and to erect the new ones against all HIV-1 variants.
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Affiliation(s)
- Jean-Charles Grivel
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, USA
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2
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Drachman DA. Commentary on “Diagnosis of Alzheimer's disease: Two decades of progress.” Alzheimer's Disease: Years of Progress, and an Army of Researchers Recruited; AD Remains an Elusive Adversary. Alzheimers Dement 2005; 1:109-11. [DOI: 10.1016/j.jalz.2005.09.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2005] [Accepted: 09/28/2005] [Indexed: 10/25/2022]
Affiliation(s)
- David A. Drachman
- Department of NeurologyUniversity of Massachusetts Medical Center55 Lake Ave NWorcesterMA01655USA
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3
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4
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Gibbons C, Kollmann TR, Pettoello-Mantovani M, Kim A, Goldstein H. Thy/Liv-SCID-Hu mice implanted with human intestine: an in vivo model for investigation of mucosal transmission of HIV. AIDS Res Hum Retroviruses 1997; 13:1453-60. [PMID: 9390744 DOI: 10.1089/aid.1997.13.1453] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Mucosal transmission is a major route by which individuals become infected with HIV. Investigation into the mechanism by which mucosal transmission of HIV occurs would be greatly facilitated by the development of a small animal model infectible with HIV by the mucosal route. We have previously described a SCID-hu mouse model, in which human thymic and liver tissues are implanted under both kidney capsules (thy/liv-SCID-hu mice), which are populated in the periphery with high numbers of human T cells and that develop disseminated HIV-1 infection after intraperitoneal injection. To expand further the usefulness of the thy/liv-SCID-hu mouse as a model for studying mucosal transmission of HIV, thy/liv-SCID-hu mice were subcutaneously implanted with human intestinal tissue in a manner that maintained the lumen. Four months later, the histological appearance of the implanted intestine resembled that of normal human bowel tissue and the lamina propria was populated with human T cells. Six weeks after introduction of HIV into the lumen of the intestinal implant, the mice developed disseminated HIV infection. Scattered HIV-infected cells were detected in the lamina propria of the implant, indicating that HIV infection in these mice was mediated by transmission of the virus across the mucosa of the human intestinal implant. Thus, our modified thy/liv-SCID-hu mice transplanted with human bowel tissue should provide a novel model for investigating mucosal transmission of HIV.
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Affiliation(s)
- C Gibbons
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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5
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Mosier DE. Human immunodeficiency virus infection of human cells transplanted to severe combined immunodeficient mice. Adv Immunol 1996; 63:79-125. [PMID: 8787630 DOI: 10.1016/s0065-2776(08)60855-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- D E Mosier
- Department of Immunology, The Scripps Research Institute, La Jolla, California 92037, USA
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6
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Sieburg HB. Methods in the Virtual Wetlab I: rule-based reasoning driven by nearest-neighbor lattice dynamics. Artif Intell Med 1994; 6:301-19. [PMID: 7812425 DOI: 10.1016/0933-3657(94)90035-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We describe a discrete dynamical systems approach to exploring the hypothesis-trees associated with wetlab experiments. On-going applications of the method to experimental research using a genetically engineered mouse animal model with severe combined immune deficiency (SCID) in the area of HIV infection are outlined as an example. In conclusion, we survey how this method can be used to engineer an informational murine, called Cybermouse [Mus Cyberspacea], that can be experimented upon using current immersion technologies.
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Affiliation(s)
- H B Sieburg
- Laboratory for Biological Informatics & Theoretical Medicine, University of California, San Diego, La Jolla 92093-0603
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7
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Stamatatos L, Cheng-Mayer C. Evidence that the structural conformation of envelope gp120 affects human immunodeficiency virus type 1 infectivity, host range, and syncytium-forming ability. J Virol 1993; 67:5635-9. [PMID: 8350416 PMCID: PMC237967 DOI: 10.1128/jvi.67.9.5635-5639.1993] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
We investigated how amino acid changes within and outside the V3 loop of the envelope glycoprotein of human immunodeficiency virus type 1 influence the infectivity, host range, and syncytium-forming ability of the virus. Our studies show that on the genomic backgrounds of the human immunodeficiency virus type 1 strains SF2 and SF13, a reciprocal exchange of full-loop sequences does not alter the syncytium-forming ability of the viruses, indicating that a determinant(s) for this biological property maps outside the loop. However, specific amino acid substitutions, both within and outside the V3 loop, resulted in loss of infectivity, host range, and syncytium-forming potential of the virus. Furthermore, it appears that a functional interaction of the V3 loop with regions in the C2 domain of envelope gp120 plays a role in determining these biological properties. Structural studies of mutant glycoproteins show that the mutations introduced affect the proper association of gp120 with the transmembrane glycoprotein gp41. Our results suggest that mutations that alter the structure of the V3 loop can affect the overall conformation of gp120 and that, reciprocally, the structure of the V3 loop is influenced by the conformation of other regions of gp120. Since the changes in the replicative potential, host range, and fusogenic ability of the mutant viruses correlate well with the changes in gp120 conformation, as monitored by the association of gp120 with gp41, our results support a close relationship between envelope gp120 structural conformation and the biological phenotype of the virus.
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Affiliation(s)
- L Stamatatos
- Cancer Research Institute, School of Medicine, University of California, San Francisco 94143-0128
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8
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Affiliation(s)
- J A Levy
- Department of Medicine, University of California, School of Medicine, San Francisco 94143-0128
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9
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Abstract
There are several theories of the pathogenesis of HIV that attempt to explain the long and variable delay between infection and disease. Here, each theory is reviewed within the context of a simple mathematical model of the interactions between HIV and the immune system. From this model, a theoretical index of progression has been derived that combines elements from each proposed mechanism.
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10
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Davis BR. Cell tropism and HIV infection. J Clin Apher 1993; 8:13-8. [PMID: 8505277 DOI: 10.1002/jca.2920080105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- B R Davis
- Geraldine Brush Cancer Research Institute, San Francisco, CA 94115
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11
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Koken SE, van Wamel JL, Goudsmit J, Berkhout B, Geelen JL. Natural variants of the HIV-1 long terminal repeat: analysis of promoters with duplicated DNA regulatory motifs. Virology 1992; 191:968-72. [PMID: 1448931 DOI: 10.1016/0042-6822(92)90274-s] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Sequence variation in the long terminal repeat (LTR) region of HIV-1 was analyzed in viral isolates of 17 infected individuals. Two classes of LTR size variants were found. One HIV-1 variant was detected containing an additional binding site for the transcription factor Sp1. Another LTR size variation was observed in four patients in a region just upstream of the NF-kappa B enhancer. This variation was the result of a duplication of a short DNA sequence (CTG-motif). Cell culture experiments demonstrated that the natural variant with four Sp1 sites had a slightly higher promoter activity and viral replication rate than the isogenic control LTR with three Sp1 sites. No positive effect of the duplicated CTG-motif could be detected. In order to measure small differences in virus production more accurately, equal amounts of a size variant and the wild-type plasmid were cotransfected into T-cells. The virus with four Sp1 sites did outgrow the three Sp1 virus in 35 days of culture and CTG-monomer virus outcompeted the CTG-dimer virus in 42 days. Based on these results we estimate a 5-10% difference in virus production of the LTR variants when compared to that of wild-type.
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Affiliation(s)
- S E Koken
- Department of Virology, University of Amsterdam, The Netherlands
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12
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Boyer V, Delibrias C, Noraz N, Fischer E, Kazatchkine MD, Desgranges C. Complement receptor type 2 mediates infection of the human CD4-negative Raji B-cell line with opsonized HIV. Scand J Immunol 1992; 36:879-83. [PMID: 1281336 DOI: 10.1111/j.1365-3083.1992.tb03150.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Opsonization of the HTLV-RF and HTLV-IIIB strains of HIV-1 with normal human HIV seronegative serum under conditions that allow complement activation resulted in the productive infection of cells of the Raji B lymphoblastoid cell line. Under the same experimental conditions, no infection of Raji cells was observed with unopsonized virus. Infection of Raji cells with complement-opsonized HIV-1 was totally suppressed by preblocking the function of CR2 (the C3dg receptor, CD21) on the cells with a monoclonal anti-CR2 antibody cross-linked with rabbit F(ab')2 anti-mouse immunoglobulin antibodies. Infection of Raji cells occurred independently of CD4 since the cells lacked the expression of CD4 antigen and of CD4 transcripts. Thus, Raji cells may be infected with complement-opsonized HIV independently of CD4 and in the absence of antibodies. By mediating and/or enhancing HIV infection, complement and complement receptors contribute to extend the range of target cells to the virus and may increase infection in patients with a low viral load.
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13
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Shoeman RL, Höner B, Mothes E, Traub P. Potential role of the viral protease in human immunodeficiency virus type 1 associated pathogenesis. Med Hypotheses 1992; 37:137-50. [PMID: 1584103 DOI: 10.1016/0306-9877(92)90071-j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Infection with the human immunodeficiency virus type 1 (HIV-1) results in a variety of pathological changes culminating in the acquired immune deficiency syndrome (AIDS). While most of these changes can readily be accounted for either by direct effects of HIV-1 on the immune system or by indirect effects of secondary infectious agents as a result of faulty immune surveillance, the direct cause for a number of disease states, including some neuropathies, myopathies, nephropathy, thrombocytopenia, wasting syndromes and increased incidence of cancers (primarily lymphoma) has remained an enigma. We have recently shown that the HIV-1 protease, a viral encoded enzyme necessary for virus maturation and infectivity, can cleave a variety of host cell cytoskeletal proteins in vitro. Potential substrates for the HIV-1 protease are found in all of the cell types affected in these unexplained diseases. Recent proposals suggest that elements of the cytoskeleton may play an important role in the regulation of large scale genetic regulation. We propose that some of the degenerative changes associated with infection by HIV-1 are a direct consequence of cleavage of host cell cytoskeletal proteins, which in turn may be responsible for the increased incidence of cancer in HIV-1 infected individuals as a result of the perturbation of the regulation of gene expression by cytoskeletal components.
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Affiliation(s)
- R L Shoeman
- Max-Planck-Institut für Zellbiologie, Ladenburg, Federal Republic of Germany
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14
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Le Guern M, Levy JA. Human immunodeficiency virus (HIV) type 1 can superinfect HIV-2-infected cells: pseudotype virions produced with expanded cellular host range. Proc Natl Acad Sci U S A 1992; 89:363-7. [PMID: 1346069 PMCID: PMC48237 DOI: 10.1073/pnas.89.1.363] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In studies on viral interference, cloned T-cell lines chronically infected with human immunodeficiency virus (HIV) type 1 or HIV-2 were inoculated with several strains of these two AIDS retrovirus subtypes. HIV-2UC1-infected cells, which still express the CD4 receptor, could be superinfected with a variety of HIV-1 and HIV-2 strains. This event was accompanied by cytopathic effects in the cells and production of pseudotype virions with an expanded cellular host range. HIV-1- or HIV-2-infected clonal cell lines, which did not express CD4, could not be superinfected by any HIV strains but were coinfected after transfection of molecular clones into the persistently infected cells. These observations indicate that viral interference with HIV occurs at the cell surface and involves a down-modulation of the CD4 molecule. If the CD4 protein is expressed, superinfection can take place, and phenotypically mixed virus particles are produced. Since HIV-1 and HIV-2 dually infected individuals have been detected, these in vitro observations may have relevance to the in vivo state.
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Affiliation(s)
- M Le Guern
- Cancer Research Institute, University of California, School of Medicine, San Francisco 94143-0128
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15
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Cheng-Mayer C, Shioda T, Levy JA. Host range, replicative, and cytopathic properties of human immunodeficiency virus type 1 are determined by very few amino acid changes in tat and gp120. J Virol 1991; 65:6931-41. [PMID: 1658383 PMCID: PMC250799 DOI: 10.1128/jvi.65.12.6931-6941.1991] [Citation(s) in RCA: 120] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) isolates display differences in a variety of in vitro biological properties, including the ability to infect different cell types, the kinetics of replication, and cytopathicity in the infected cells. Studies with isolates obtained from the same individual over time have shown that these in vitro properties of the viral isolates correlate with pathogenicity in the host. The later isolates, recovered when disease has developed, display a wider cellular host range, replicate rapidly and to high titers in the infected cells, and induce syncytia in these cells. In the present studies, the genomic determinants of these biological properties were defined with recombinant viruses generated between two HIV-1 isolates recovered sequentially from the same individual. The results show that the rate of HIV-1 replication in the HUT 78 T-cell line is controlled by the first coding exon of tat. Infection of T-cell and monocytic cell lines is determined by two specific regions in the envelope gp120, one of which also confers the ability of an isolate to induce syncytia. Amino acid sequence comparison of the regions identified revealed minor differences between the two viral isolates: 2 amino acids in the tat gene product and 10 and 12 amino acids in the two regions of envelope gp120. These data suggest that small changes in the tat and env proteins can have dramatic effects on the pathogenic potential of HIV-1.
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Affiliation(s)
- C Cheng-Mayer
- Cancer Research Institute, University of California School of Medicine, San Francisco 94143-0128
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16
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Tang SB, Levy JA. Inactivation of HIV-1 by trypsin and its use in demonstrating specific virus infection of cells. J Virol Methods 1991; 33:39-46. [PMID: 1682337 DOI: 10.1016/0166-0934(91)90005-k] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
HIV-1 was found sensitive to inactivation by low concentrations of trypsin. The use of trypsin was valuable for assessing non-specific binding of HIV virions to CD4+ cells. This effect was also helpful for eliminating input virus in experiments studying HIV infection of cells in vitro.
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Affiliation(s)
- S B Tang
- Cancer Research Institute, University of California, School of Medicine, San Francisco 94143-0128
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17
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Chehimi J, Bandyopadhyay S, Prakash K, Perussia B, Hassan NF, Kawashima H, Campbell D, Kornbluth J, Starr SE. In vitro infection of natural killer cells with different human immunodeficiency virus type 1 isolates. J Virol 1991; 65:1812-22. [PMID: 1672164 PMCID: PMC239989 DOI: 10.1128/jvi.65.4.1812-1822.1991] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Natural killer (NK) cells are a discrete subset of leukocytes, distinct from T and B lymphocytes. NK cells mediate spontaneous non-MHC-restricted killing of a wide variety of target cells without prior sensitization and appear to be involved in initial protection against certain viral infections. Depressed NK cell-mediated cytotoxicity, one of the many immunological defects observed in AIDS patients, may contribute to secondary virus infections. Here we report that clonal and purified polyclonal populations of NK cells, which expressed neither surface CD4 nor CD4 mRNA, were susceptible to infection with various isolates of human immunodeficiency virus type 1 (HIV-1). Viral replication was demonstrated by detection of p24 antigen intracellularly and in culture supernatants, by the presence of HIV DNA within infected cells, and by the ability of supernatants derived from HIV-infected NK cells to infect peripheral blood mononuclear cells or CD4+ cell lines. Infection of NK cells was not blocked by anti-CD4 or anti-Fc gamma RIII monoclonal antibodies. NK cells from HIV-infected and uninfected cultures were similar in their ability to lyse three different target cells. Considerable numbers of cells died in HIV-infected NK cell cultures. These results suggest that loss of NK cells in AIDS patients is a direct effect of HIV infection but that reduced NK cell function involves another mechanism. The possibility that NK cells serve as a potential reservoir for HIV-1 must be considered.
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MESH Headings
- Acquired Immunodeficiency Syndrome/genetics
- Acquired Immunodeficiency Syndrome/immunology
- Acquired Immunodeficiency Syndrome/pathology
- Antibodies, Monoclonal/immunology
- Antigens, Differentiation/immunology
- CD4 Antigens/genetics
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/microbiology
- Cells, Cultured
- DNA, Viral/analysis
- Gene Products, gag/immunology
- HIV Core Protein p24
- HIV-1/genetics
- HIV-1/growth & development
- HIV-1/immunology
- Humans
- In Vitro Techniques
- Killer Cells, Natural/immunology
- Killer Cells, Natural/microbiology
- Kinetics
- Phenotype
- RNA, Messenger/analysis
- Receptors, Fc/immunology
- Receptors, IgG
- Viral Core Proteins/immunology
- Virus Replication
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Affiliation(s)
- J Chehimi
- Division of Infectious Diseases and Immunology, Joseph Stokes, Jr. Research Institute, Chiildren's Hospital of Philadelphia, Pennsylvania
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18
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Cheng-Mayer C, Seto D, Levy JA. Altered host range of HIV-1 after passage through various human cell types. Virology 1991; 181:288-94. [PMID: 1994578 DOI: 10.1016/0042-6822(91)90494-v] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
HIV-1 strains, including a molecularly cloned isolate, that had been passaged through different cell types adapted to faster growth in the same cell type and displayed a different host cell tropism. The only change in viral proteins revealed by immunoblot analyses was the molecular size of the envelope glycoprotein gp120 that varied for viruses recovered from the different infected cells. The alteration in size was most likely the result of modification of gp120. Host range differences were also observed for a molecularly cloned HIV-1 strain when passed through the peripheral white blood cells from different individuals. Thus, this phenomenon could have clinical relevance in HIV pathogenesis.
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Affiliation(s)
- C Cheng-Mayer
- Cancer Research Institute, University of California, San Francisco 94143
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19
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Affiliation(s)
- W C Greene
- Department of Medicine, Howard Hughes Medical Institute, Durham, NC
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20
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Macrophage and T cell-line tropisms of HIV-1 are determined by specific regions of the envelope gp120 gene. Nature 1991; 349:167-9. [PMID: 1986308 DOI: 10.1038/349167a0] [Citation(s) in RCA: 449] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Strains of human immunodeficiency virus type 1 (HIV-1) display a high degree of biological heterogeneity which may be linked to certain clinical manifestation of AIDS. They vary in their ability to infect different cell types, to replicate rapidly and to high titre in culture, to down-modulate the CD4 receptor, and to cause cytopathic changes in infected cells. Some of these in vitro properties correlate with pathogenicity of the virus in vivo. To map the viral determinants of the cellular host range of HIV-1, recombinant viruses were generated between biologically active molecular clones of HIV-1 isolates showing differences in infection of primary peripheral blood macrophages and established T-cell lines. We report here that a specific region of the envelope gp120 gene representing 159 amino-acid residues of glycoprotein gp120 seems to determine macrophage tropism, whereas an overlapping region representing 321 amino-acid residues determines T cell-line tropism. These studies provide a basis for relating functional domains of the HIV-1 env gene to pathogenic potential.
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21
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Levy JA. Viral and cellular factors influencing HIV tropism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1991; 300:1-15. [PMID: 1685854 DOI: 10.1007/978-1-4684-5976-0_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- J A Levy
- Department of Medicine, University of California, School of Medicine, San Francisco 94143-0128
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22
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Fiore JR, Calabró ML, Angarano G, De Rossi A, Fico C, Pastore G, Bianchi LC. HIV-1 variability and progression to AIDS: a longitudinal study. J Med Virol 1990; 32:252-6. [PMID: 1982010 DOI: 10.1002/jmv.1890320411] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
HIV-1 replicative activity and its relation to the clinical and immunological evolution of infection was studied in a group of 150 HIV-1 seropositive Italian i.v. drug abusers over a 1 year period. HIV-1 was isolated from 90 (60%) subjects; two groups of isolates were distinguished, according to replicative activity "in vitro" and ability to induce cytopathic effects in cell cultures, and were termed "rapid-high" and "slow-low" viruses, in agreement with other workers. Rapid-high viruses were recovered more frequently from patients with ARC/AIDS, while slow-low viruses seemed related to the asymptomatic period of infection. The replicative properties of HIV-1 seem to affect strongly the course of disease. In fact, an important CD4 cell decline occurred in asymptomatic subjects with rapid-high virus infection; asymptomatic subjects with negative viral cultures or with slow-low viruses showed no such decline. Asymptomatic subjects with negative viral cultures had no signs of disease during the observation period, while 9% with slow-low virus and 45% with rapid-high virus progressed to AIDS.
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Affiliation(s)
- J R Fiore
- Clinic of Infectious Diseases, University of Bari, Italy
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23
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Cheng-Mayer C, Quiroga M, Tung JW, Dina D, Levy JA. Viral determinants of human immunodeficiency virus type 1 T-cell or macrophage tropism, cytopathogenicity, and CD4 antigen modulation. J Virol 1990; 64:4390-8. [PMID: 2384920 PMCID: PMC247907 DOI: 10.1128/jvi.64.9.4390-4398.1990] [Citation(s) in RCA: 216] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The genome of the human immunodeficiency virus type 1 (HIV-1) is highly heterogeneous. Some of this genomic variability is reflected in the biologic and serologic differences observed among various strains of HIV-1. To map the viral determinants that correlate with pathogenicity of the virus, recombinant viruses were generated between biologically active molecular clones of HIV-1 strains that show differences in T-cell or macrophage tropism, cytopathogenicity, CD4 antigen modulation, and susceptibility to serum neutralization. The results of these studies indicate that the envelope region contains the major determinants of these viral features. Further studies with sequence exchanges within this region should help identify specific domains that contribute to HIV pathogenesis.
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Affiliation(s)
- C Cheng-Mayer
- Cancer Research Institute, University of California, San Francisco 94143
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24
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Velpandi A, Monken CE, Srinivasan A. Development of RD-tat cell lines: use in HIV recombination studies. J Virol Methods 1990; 29:291-302. [PMID: 2125054 DOI: 10.1016/0166-0934(90)90056-l] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The transactivator (tat) gene of human immunodeficiency virus (HIV) plays an essential role in the replication cycle of HIV. Previous studies have evaluated the extent and mechanistic aspects of tat-mediated transactivation using lymphoid and adherent non-lymphoid cells. We have exploited the transactivation property of the tat gene to achieve high levels of hybrid HIV resulting from recombination between HIV DNAs. For this purpose, we have generated stably transformed human rhabdomyosarcoma (RD) cell lines expressing tat gene product of HIV-1. Functional analysis of the cell lines for the presence of tat protein by transfecting HIV-long terminal repeat (LTR) linked to chloramphenicol acetyl transferase (CAT) revealed low, moderate, and high tat producer cell lines. RD-tat cell lines also showed enhanced virus production upon transfection of HIV-1 proviral DNA. Further, tat producer cell lines showed a high amount of hybrid virus in comparison to the control RD cells upon transfection of truncated viral DNAs. Thus, RD-tat cell lines would be valuable target cells for generating homogeneous viruses upon transfection of viral DNA.
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Affiliation(s)
- A Velpandi
- Wistar Institute of Anatomy and Biology, Philadelphia, Pennsylvania 19104
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Sattentau QJ. Interactions of HIV gp120 with the CD4 molecule on lymphocytes and in the nervous system. Ann N Y Acad Sci 1990; 594:355-61. [PMID: 2198840 DOI: 10.1111/j.1749-6632.1990.tb40494.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Q J Sattentau
- Howard Hughes Medical Institute, College of Physicians and Surgeons, Columbia University, New York, New York 10032
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Abstract
Human T-helper cells express membrane-bound CD4 antigen whose many epitopes are recognized by different monoclonal antibodies. The epitope recognized by Leu-3a and similar clones has been shown to be the location for human immunodeficiency virus (HIV) receptor. We have found a unique blood donor whose CD4+ T-helper lymphocytes were lacking Leu-3a epitope. CD4+ T-helper cells lacking Leu-3a epitope might be resistant to HIV infection.
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Affiliation(s)
- C V Angadi
- Department of Pathology, Nassau County Medical Center, Stony Brook, East Meadow, New York
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Abstract
Surveillance for AIDS/HIV infection is essential for planning, implementing and evaluating AIDS control programs. Each of the different methods used, AIDS surveillance, surveillance for HIV infection and HIV seroprevalence, sero-incidence studies in selected populations, have advantages and disadvantages. A combination of these methods is generally needed to accurately monitor the HIV epidemic, and the methods used will depend on the objectives of the surveillance system. Surveillance data need to be adequately analyzed and made available to the public, public health planners, health care professionals and politicians. Most importantly, surveillance data need to be used for preventive action.
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