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Gong K, Lai Y. Development trends of immune activation during HIV infection in recent three decades: a bibliometric analysis based on CiteSpace. Arch Microbiol 2023; 205:283. [PMID: 37432538 DOI: 10.1007/s00203-023-03624-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 06/18/2023] [Accepted: 07/02/2023] [Indexed: 07/12/2023]
Abstract
This study aimed to evaluate and pinpoint the status, hot areas, and frontiers of immune activation during HIV infection utilizing CiteSpace. From 1990 to 2022, we searched for studies on immune activation during HIV infection in the Web of Science Core Collection. CiteSpace was used to visually analyze the publications to identify the research status and pertinent research hotspots and frontiers in terms of the countries, institutions, authors, references, journals, and keywords. The Web of Science Core Collection yielded 5321 articles on immune activation during HIV infection. With 2854 and 364 articles, the United States and the University of California, San Francisco were the leading nation and institution in this domain. Steven G. Deeks has published 95 papers and is the most published author. The top cited articles on microbial translocation as a significant factor during HIV infection were published by Brenchley et al. Research on molecular/biology/genetics is often referenced in publications in the journals of molecular/biology/immunology. Inflammation, risk, mortality, cardiovascular disease, persistence, and biomarkers will be high-frequency words that are hot topics of research. According to the results, there was a strong collaboration between countries and organizations but little collaboration among authors. Molecular biology, immunology, and medicine are the main study subjects. The current hot topics in research are inflammation, risk, mortality, cardiovascular disease, persistence, and biomarkers. Future studies should concentrate on reducing the pathological changes caused by inflammation and altering the mechanisms of immune activation to reduce the size of the viral reservoir.
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Affiliation(s)
- Kang Gong
- School of Clinical Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Yu Lai
- School of Basic Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
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Keating SM, Heitman JW, Wu S, Deng X, Stacey AR, Zahn RC, de la Rosa M, Finstad SL, Lifson JD, Piatak M, Gauduin MC, Kessler BM, Ternette N, Carville A, Johnson RP, Desrosiers RC, Letvin NL, Borrow P, Norris PJ, Schmitz JE. Magnitude and Quality of Cytokine and Chemokine Storm during Acute Infection Distinguish Nonprogressive and Progressive Simian Immunodeficiency Virus Infections of Nonhuman Primates. J Virol 2016; 90:10339-10350. [PMID: 27630228 PMCID: PMC5105668 DOI: 10.1128/jvi.01061-16] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 08/24/2016] [Indexed: 12/23/2022] Open
Abstract
Acute human immunodeficiency virus (HIV) infection represents a period of intense immune perturbation and activation of the host immune system. Study of the eclipse and viral expansion phases of infection is difficult in humans, but studies in nonprogressive and progressive nonhuman primate (NHP) infection models can provide significant insight into critical events occurring during this time. Cytokines, chemokines, and other soluble immune factors were measured in longitudinal samples from rhesus macaques infected with either SIVmac251 (progressive infection) or SIVmac239Δnef (attenuated/nonprogressive infection) and from African green monkeys infected with SIVsab9315BR (nonpathogenic infection). Levels of acute-phase peak viral replication were highest in SIVmac251 infection but correlated positively with viremia at 3 months postinfection in all three infection models. SIVmac251 infection was associated with stronger corresponding acute-phase cytokine/chemokine responses than the nonprogressive infections. The production of interleukin 15 (IL-15), IL-18, gamma interferon (IFN-γ), granulocyte colony-stimulating factor (G-CSF), monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein 1β (MIP-1β), and serum amyloid A protein (SAA) during acute SIVmac251 infection, but not during SIVmac239Δnef or SIVsab9315BR infection, correlated positively with chronic viremia at 3 months postinfection. Acute-phase production of MCP-1 correlated with viremia at 3 months postinfection in both nonprogressive infections. Finally, a positive correlation between the acute-phase area under the curve (AUC) for IL-6 and soluble CD40 ligand (sCD40L) and chronic viremia was observed only for the nonprogressive infection models. While we observed dynamic acute inflammatory immune responses in both progressive and nonprogressive SIV infections, the responses in the nonprogressive infections were not only lower in magnitude but also qualitatively different biomarkers of disease progression. IMPORTANCE NHP models of HIV infection constitute a powerful tool with which to study viral pathogenesis in order to gain critical information for a better understanding of HIV infection in humans. Here we studied progressive and nonprogressive simian immunodeficiency virus (SIV) infection models in both natural and nonnatural host NHP species. Regardless of the pathogenicity of the virus infection and regardless of the NHP species studied, the magnitude of viremia, as measured by area under the curve, during the first 4 weeks of infection correlated positively with viremia in chronic infection. The magnitude of cytokine and chemokine responses during primary infection also correlated positively with both acute-phase and chronic viremia. However, the pattern and levels of specific cytokines and chemokines produced differed between nonprogressive and progressive SIV infection models. The qualitative differences in the early immune response in pathogenic and nonpathogenic infections identified here may be important determinants of the subsequent disease course.
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Affiliation(s)
- Sheila M Keating
- Blood Systems Research Institute, San Francisco, California, USA
- Department of Laboratory Medicine, University of California, San Francisco, California, USA
| | - John W Heitman
- Blood Systems Research Institute, San Francisco, California, USA
| | - Shiquan Wu
- Blood Systems Research Institute, San Francisco, California, USA
| | - Xutao Deng
- Blood Systems Research Institute, San Francisco, California, USA
| | - Andrea R Stacey
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Roland C Zahn
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA
| | - Maurus de la Rosa
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA
| | - Samantha L Finstad
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Michael Piatak
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Marie-Claire Gauduin
- Texas Biomedical Research Institute, Department of Virology and Immunology and Southwest National Primate Research Center, San Antonio, Texas, USA
| | - Benedikt M Kessler
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
- Target Discovery Institute, University of Oxford, Oxford, United Kingdom
| | - Nicola Ternette
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
- Target Discovery Institute, University of Oxford, Oxford, United Kingdom
| | - Angela Carville
- Department of Primate Resources, New England Primate Research Center, Southborough, Massachusetts, USA
| | - R Paul Johnson
- Department of Immunology, New England Primate Research Center, Southborough, Massachusetts, USA
| | - Ronald C Desrosiers
- Department of Microbiology, New England Primate Research Center, Southborough, Massachusetts, USA
| | - Norman L Letvin
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA
| | - Persephone Borrow
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Philip J Norris
- Blood Systems Research Institute, San Francisco, California, USA
- Department of Laboratory Medicine, University of California, San Francisco, California, USA
- Department of Medicine, University of California, San Francisco, California, USA
| | - Joern E Schmitz
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA
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Kroidl I, Saathoff E, Maganga L, Makunde WH, Hoerauf A, Geldmacher C, Clowes P, Maboko L, Hoelscher M. Effect of Wuchereria bancrofti infection on HIV incidence in southwest Tanzania: a prospective cohort study. Lancet 2016; 388:1912-1920. [PMID: 27495354 DOI: 10.1016/s0140-6736(16)31252-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 07/08/2016] [Accepted: 07/13/2016] [Indexed: 12/20/2022]
Abstract
BACKGROUND The past decades have seen an ongoing controversial debate about whether the immune activation induced by helminths has an effect on the susceptibility of individuals to HIV. In view of this, we assessed the effect of lymphatic filariasis, a chronic helminth disease elicited by Wuchereria bancrofti, on HIV incidence in southwest Tanzania. METHODS In this population-based cohort study, we enrolled a geographically stratified randomly chosen sample of about 10% of the households in nine distinct sites in southwest Tanzania. All household members present were followed up and tested for HIV and circulating filarial antigen, an indicator of W bancrofti adult worm burden. Our main outcome of interest was HIV incidence in participants with or without lymphatic filariasis. FINDINGS Between May 29, 2006, and June 16, 2011, we enrolled 4283 households with roughly 18 000 participants. Of these, 2699 individuals from Kyela district participated in at least one round of the EMINI study. In the 1055 initially HIV-negative adolescents and adults with clearly defined lymphatic filariasis status, 32 new HIV infections were observed in 2626 person-years. HIV incidence in lymphatic filariasis-positive participants (1·91 cases per 100 person-years) was significantly higher than the incidence in lymphatic filariasis-negative participants (0·80 cases per 100 person-years). The age-adjusted and sex-adjusted incidence rate ratio was 2·17 (95% CI 1·08-4·37, p=0·0300). Lymphatic filariasis status remained an independent and significantly relevant risk factor for HIV infection when controlled for other known risk factors such as sexual behaviour and socioeconomic factors. INTERPRETATION To our knowledge, this is the first prospective study demonstrating a significantly increased risk of acquiring HIV for lymphatic filariasis-infected individuals. Immunological studies and interventional treatment studies that eliminate the adult worms and not only the microfilariae are needed to follow up on the results presented. FUNDING European Union as part of EuropAid; German Federal Ministry of Education and Research; German Center for Infection Research.
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Affiliation(s)
- Inge Kroidl
- Division of Infectious Diseases and Tropical Medicine, Medical Center of the University of Munich, Munich, Germany; National Institute of Medical Research, Mbeya Medical Research Centre, Mbeya, Tanzania; German Center for Infection Research (DZIF), partner site Munich, Munich, Germany.
| | - Elmar Saathoff
- Division of Infectious Diseases and Tropical Medicine, Medical Center of the University of Munich, Munich, Germany; German Center for Infection Research (DZIF), partner site Munich, Munich, Germany
| | - Lucas Maganga
- National Institute of Medical Research, Mbeya Medical Research Centre, Mbeya, Tanzania
| | | | - Achim Hoerauf
- Institute of Medical Microbiology, Immunology and Parasitology, University Hospital of Bonn, Bonn, Germany; German Center for Infection Research (DZIF), partner site Bonn-Cologne, Bonn-Cologne, Germany
| | - Christof Geldmacher
- Division of Infectious Diseases and Tropical Medicine, Medical Center of the University of Munich, Munich, Germany; German Center for Infection Research (DZIF), partner site Munich, Munich, Germany
| | - Petra Clowes
- National Institute of Medical Research, Mbeya Medical Research Centre, Mbeya, Tanzania
| | - Leonard Maboko
- National Institute of Medical Research, Mbeya Medical Research Centre, Mbeya, Tanzania
| | - Michael Hoelscher
- Division of Infectious Diseases and Tropical Medicine, Medical Center of the University of Munich, Munich, Germany; National Institute of Medical Research, Mbeya Medical Research Centre, Mbeya, Tanzania; German Center for Infection Research (DZIF), partner site Munich, Munich, Germany
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Kinchington D, Ng T, Mathews N, Tisdale M, Devine D, Ayuko WO. T Cell Costimulation by Derivatives of Benzoic Acid. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/095632029700800206] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A number of analogues of benzoic acid were evaluated in a T cell costimulation assay. One compound, the sodium salt of 2-chloro-5-nitrobenzoic acid (CNBA-Na) was chosen for further study and was found to be a potent costimulator of anti-CD3-induced proliferation of both H9 lymphoblastoid cells ( P<0.001) and human peripheral blood mononuclear cells ( P=0.001) in a dose-dependent manner. The costimulatory effect of CNBA-Na on CD3-triggered DNA synthesis did not enhance human immunodeficiency virus replication in infected cells. Studies with blocking monoclonal antibodies against B7-1 or B7-2 indicated that the immunopotentiatory effect of CNBA-Na required a macromolecular interaction between CD28 (a costimulatory receptor on T cells) and its counter receptor B7 expressed on antigen-presenting cells. The discovery that this low molecular weight compound causes T cell proliferation highlights a potentially novel therapeutic approach to immunodeficiency diseases.
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Affiliation(s)
- D Kinchington
- Department of Virology, St Bartholomew's and the Royal London School of Medicine and Dentistry, 51-53 Bartholomew Place, West Smithfield, London EC1A 7BE, UK
| | - T Ng
- Department of Immunology, St Bartholomew's and the Royal London School of Medicine and Dentistry, 38 Little Britain, West Smithfield, London EC1A 7BE, UK
| | - N Mathews
- Department of Virology, St Bartholomew's and the Royal London School of Medicine and Dentistry, 51-53 Bartholomew Place, West Smithfield, London EC1A 7BE, UK
| | - M Tisdale
- Pharmaceutical Sciences Institute, Aston University, Aston Triangle, Birmingham B4 7ET, UK
| | - D Devine
- Department of Virology, St Bartholomew's and the Royal London School of Medicine and Dentistry, 51-53 Bartholomew Place, West Smithfield, London EC1A 7BE, UK
| | - WO Ayuko
- Pharmaceutical Sciences Institute, Aston University, Aston Triangle, Birmingham B4 7ET, UK
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Mahmud MA, Bezabih AM, Gebru RB. Risk factors for intestinal parasitosis among antiretroviral-treated HIV/AIDS patients in Ethiopia. Int J STD AIDS 2014; 25:778-84. [PMID: 24554001 DOI: 10.1177/0956462414520803] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Summary A cross-sectional survey was conducted to determine the risk factors associated with intestinal parasitosis in HIV/AIDS patients receiving antiretroviral therapy (ART). Socio-demographic information was collected and faecal samples were analysed from 384 randomly selected patients on ART. Data on CD4+ T-cell counts and World Health Organization clinical staging were obtained from the medical records at the hospital. The overall prevalence of intestinal parasitosis was 56% (95% confidence interval [CI]: 51% to 61%). No opportunistic intestinal parasites or Schistosoma haematobium eggs were detected. Unavailability of latrine and lack of hand washing with soap were associated with Entamoeba histolytica/dispar (adjusted odds ratio [AOR], 2.75; 95% CI: 1.77 to 4.27 and AOR, 2.67; 95% CI: 1.60 to 4.44, respectively) and Giardia lamblia (AOR, 2.08; 95% CI: 1.08 to 3.99 and AOR, 2.46; 95% CI: 1.06 to 5.75, respectively) infections. Intestinal parasitosis was significantly associated with low CD4 cell count (p = 0.002). In contrast, intestinal parasitic infections were not associated (p > 0.05) with the World Health Organization disease staging. In summary, poor personal hygiene and sanitation practice contributed to the high prevalence of intestinal parasitosis. Routine diagnosis for intestinal parasitic infections should be performed in patients attending ART clinics in this setting.
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Affiliation(s)
- Mahmud Abdulkader Mahmud
- Mahmud Abdulkader Mahmud, Department of Microbiology and Immunology, College of Health Sciences, Mekelle University, Mekelle, Ethiopia
| | | | - Rezene Berhe Gebru
- Department of Internal Medicine, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
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Manches O, Frleta D, Bhardwaj N. Dendritic cells in progression and pathology of HIV infection. Trends Immunol 2013; 35:114-22. [PMID: 24246474 DOI: 10.1016/j.it.2013.10.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 09/24/2013] [Accepted: 10/09/2013] [Indexed: 01/08/2023]
Abstract
Although the major targets of HIV infection are CD4⁺ T cells, dendritic cells (DCs) represent a crucial subset in HIV infection because they influence viral transmission and target cell infection and presentation of HIV antigens. DCs are potent antigen-presenting cells that can modulate antiviral immune responses. Through secretion of inflammatory cytokines and interferons (IFNs), DCs also alter T cell proliferation and differentiation, participating in the immune dysregulation characteristic of chronic HIV infection. Their wide distribution in close proximity with the mucosal epithelia makes them one of the first cell types to encounter HIV during sexual transmission. We discuss here the multiple roles that DCs play at different stages of HIV infection, emphasizing their relevance to HIV pathology and progression.
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Affiliation(s)
- Olivier Manches
- Division of Hematology and Oncology, Hess Center for Science and Medicine, Mount Sinai Hospital, New York, USA
| | - Davor Frleta
- Division of Hematology and Oncology, Hess Center for Science and Medicine, Mount Sinai Hospital, New York, USA
| | - Nina Bhardwaj
- Division of Hematology and Oncology, Hess Center for Science and Medicine, Mount Sinai Hospital, New York, USA.
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Alemu A, Shiferaw Y, Addis Z, Mathewos B, Birhan W. Effect of malaria on HIV/AIDS transmission and progression. Parasit Vectors 2013; 6:18. [PMID: 23327493 PMCID: PMC3564906 DOI: 10.1186/1756-3305-6-18] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Accepted: 01/14/2013] [Indexed: 11/10/2022] Open
Abstract
Malaria and HIV are among the two most important global health problems of developing countries. They cause more than 4 million deaths a year. These two infections interact bidirectionally and synergistically with each other. HIV infection increases the risk of an increase in the severity of malaria infection and burdens of malaria, which in turn facilitates the rate of malaria transmission. Malaria infection is also associated with strong CD4+ cell activation and up-regulation of proinflammatory cytokines and it provides an ideal microenvironment for the spread of the virus among the CD4+ cells and for rapid HIV-1 replication. Additionally, malaria increases blood viral burden by different mechanisms. Therefore, high concentrations of HIV-1 RNA in the blood are predictive of disease progression, and correlate with the risk of blood-borne, vertical, and sexual transmission of the virus. Therefore, this article aims to review information about HIV malaria interactions, the effect of malaria on HIV transmission and progression and the implications related to prevention and treatment of coinfection.
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Affiliation(s)
- Abebe Alemu
- Department of Medical Parasitology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Yitayal Shiferaw
- Department of Medical Microbiology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Zelalem Addis
- Department of Medical Microbiology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Biniam Mathewos
- Department of Immunology and Molecular Biology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Wubet Birhan
- Department of Immunology and Molecular Biology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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Ormsby CE, Sengupta D, Tandon R, Deeks SG, Martin JN, Jones RB, Ostrowski MA, Garrison KE, Vázquez-Pérez JA, Reyes-Terán G, Nixon DF. Human endogenous retrovirus expression is inversely associated with chronic immune activation in HIV-1 infection. PLoS One 2012; 7:e41021. [PMID: 22879884 PMCID: PMC3413683 DOI: 10.1371/journal.pone.0041021] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Accepted: 06/16/2012] [Indexed: 01/06/2023] Open
Abstract
Human endogenous retroviruses (HERV) are remnants of ancestral retroviral infections integrated into the germ line, and constitute approximately 8% of the genome. Several autoimmune disorders, malignancies, and infectious diseases such as HIV-1 are associated with higher HERV expression. The degree to which HERV expression in vivo results in persistent inflammation is not known. We studied the association of immune activation and HERV-K expression in 20 subjects with chronic, untreated progressive HIV-1 infection and 10 HIV-1 negative controls. The mean HERV-K gag and env RNA expression level in the HIV-1 infected cohort was higher than in the control group (p = 0.0003), and was negatively correlated with the frequency of activated CD38+HLA-DR+CD4+ T cells (Rho = -0.61; p = 0.01) and activated CD38+HLA-DR+CD8+ T cells (Rho = -0.51; p = 0.03). Although HIV-infected persons had higher levels of HERV-K RNA expression (as expected), the level of RNA expression was negatively associated with level of T cell activation. The mechanism for this unexpected association remains to be defined.
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Affiliation(s)
- Christopher E Ormsby
- Center for Research in Infectious Diseases, National Institute of Respiratory Diseases, Mexico City, Federal District, Mexico.
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Ahmed Z, Czubala M, Blanchet F, Piguet V. HIV impairment of immune responses in dendritic cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 762:201-38. [PMID: 22975877 DOI: 10.1007/978-1-4614-4433-6_8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Dendritic cells and their subsets are diverse populations of immune cells in the skin and mucous membranes that possess the ability to sense the presence of microbes and orchestrate an efficient and adapted immune response. Dendritic cells (DC) have the unique ability to act as a bridge between the innate and adaptive immune responses. These cells are composed of a number of subsets behaving with preferential and specific features depending on their location and surrounding environment. Langerhans cells (LC) or dermal DC (dDC) are readily present in mucosal areas. Other DC subsets such as plasmacytoid DC (pDC), myeloid DC (myDC), or monocyte-derived DC (MDDC) are thought to be recruited or differentiated in sites of pathogenic challenge. Upon HIV infection, DC and their subsets are likely among the very first immune cells to encounter incoming pathogens and initiate innate and adaptive immune responses. However, as evidenced during HIV infection, some pathogens have evolved subtle strategies to hijack key cellular machineries essential to generate efficient antiviral responses and subvert immune responses for spread and survival.In this chapter, we review recent research aimed at investigating the involvement of DC subtypes in HIV transmission at mucosal sites, concentrating on HIV impact on cellular signalling and trafficking pathways in DC leading to DC-mediated immune response alterations and viral immune evasion. We also address some aspects of DC functions during the chronic immune pathogenesis and conclude with an overview of the current and novel therapeutic and prophylactic strategies aimed at improving DC-mediated immune responses, thus to potentially tackle the early events of mucosal HIV infection and spread.
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Affiliation(s)
- Zahra Ahmed
- Department of Dermatology and Wound Healing, Cardiff University School of Medicine, Cardiff, Wales, UK
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Katsikis PD, Mueller YM, Villinger F. The cytokine network of acute HIV infection: a promising target for vaccines and therapy to reduce viral set-point? PLoS Pathog 2011; 7:e1002055. [PMID: 21852945 PMCID: PMC3154847 DOI: 10.1371/journal.ppat.1002055] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Cytokines play a central role in the pathogenesis of many diseases, including HIV infection. However, the role of the cytokine network in early HIV infection is only now starting to be elucidated. A number of studies conducted in recent years have indicated that cytokines of the acute/early stages of HIV and SIV infection can impact viral set-point months later, and this is of critical importance since viral set-point during chronic HIV infection affects virus transmission and disease progression. This raises the question whether modulating the cytokine environment during acute/early HIV infection can be a target for novel approaches to develop a vaccine and therapeutics. In this review we focus on the kinetics and function of cytokines during acute HIV and SIV infection and how these may impact viral set-point. We also discuss unresolved questions that are essential for our understanding of the role of acute infection cytokines in HIV infection and that, if answered, may suggest novel therapeutic and vaccine strategies to control the worldwide HIV pandemic.
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Affiliation(s)
- Peter D. Katsikis
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Yvonne M. Mueller
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - François Villinger
- Department of Pathology and Laboratory Medicine, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, United States of America
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Evans VA, Lal L, Akkina R, Solomon A, Wright E, Lewin SR, Cameron PU. Thymic plasmacytoid dendritic cells are susceptible to productive HIV-1 infection and efficiently transfer R5 HIV-1 to thymocytes in vitro. Retrovirology 2011; 8:43. [PMID: 21639903 PMCID: PMC3118182 DOI: 10.1186/1742-4690-8-43] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Accepted: 06/03/2011] [Indexed: 01/28/2023] Open
Abstract
Background HIV-1 infection of the thymus contributes to the defective regeneration and loss of CD4+ T cells in HIV-1-infected individuals. As thymic dendritic cells (DC) are permissive to infection by HIV-1, we examined the ability of thymic DC to enhance infection of thymocytes which may contribute to the overall depletion of CD4+ T cells. We compared productive infection in isolated human thymic and blood CD11c+ myeloid DC (mDC) and CD123+ plasmacytoid DC (pDC) using enhanced green fluorescent protein (EGFP) CCR5 (R5)-tropic NL(AD8) and CXCR4 (X4)-tropic NL4-3 HIV-1 reporter viruses. Transfer of productive HIV-1 infection from thymic mDC and pDC was determined by culturing these DC subsets either alone or with sorted thymocytes. Results Productive infection was observed in both thymic pDC and mDC following exposure to R5 HIV-1 and X4 HIV-1. Thymic pDC were more frequently productively infected by both R5 and X4 HIV-1 than thymic mDC (p = 0.03; n = 6). Thymic pDC efficiently transferred productive R5 HIV-1 infection to both CD3hi (p = 0.01; mean fold increase of 6.5; n = 6) and CD3lo thymocytes (mean fold increase of 1.6; n = 2). In comparison, transfer of productive infection by thymic mDC was not observed for either X4 or R5 HIV-1. Conclusions The capacity of thymic pDC to efficiently transfer R5 HIV-1 to both mature and immature thymocytes that are otherwise refractory to R5 virus may represent a pathway to early infection and impaired production of thymocytes and CD4+ T cells in HIV-1-infected individuals.
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Affiliation(s)
- Vanessa A Evans
- Monash University, Department of Medicine, Central and Eastern Clinical School, Alfred Campus, Commercial Rd., Melbourne, Victoria 3004, Australia
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Modjarrad K, Vermund SH. Effect of treating co-infections on HIV-1 viral load: a systematic review. THE LANCET. INFECTIOUS DISEASES 2010; 10:455-63. [PMID: 20610327 DOI: 10.1016/s1473-3099(10)70093-1] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Co-infections contribute to HIV-related pathogenesis and often increase viral load in HIV-infected people. We did a systematic review to assess the effect of treating key co-infections on plasma HIV-1-RNA concentrations in low-income countries. We identified 18 eligible studies for review: two on tuberculosis, two on malaria, six on helminths, and eight on sexually transmitted infections, excluding untreatable or non-pathogenic infections. Standardised mean plasma viral load decreased after the treatment of co-infecting pathogens in all 18 studies. The standardised mean HIV viral-load difference ranged from -0.04 log(10) copies per mL (95% CI -0.24 to 0.16) after syphilis treatment to -3.47 log(10) copies per mL (95% CI -3.78 to -3.16) after tuberculosis treatment. Of 14 studies with variance data available, 12 reported significant HIV viral-load differences before and after treatment. Although many of the viral-load reductions were 1.0 log(10) copies per mL or less, even small changes in plasma HIV-RNA concentrations have been shown to slow HIV progression and could translate into population-level benefits in lowering HIV transmission risk.
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Affiliation(s)
- Kayvon Modjarrad
- Department of Medicine, Vanderbilt University School of Medicine, Medical Center, 2525 West End Avenue, Nashville, TN, USA.
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Dendritic cell-mediated HIV-1 infection of T cells demonstrates a direct relationship to plasma viral RNA levels. J Acquir Immune Defic Syndr 2010; 54:115-21. [PMID: 20386455 DOI: 10.1097/qai.0b013e3181daaf98] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To examine the relationship between infectivity of HIV-1 variants in dendritic cell (DC)-mediated in trans infection of T cells and plasma viral RNA levels in infected subjects. METHODS HIV-1 was isolated from peripheral blood mononuclear cells of chronically infected individuals, typed for coreceptor usage, and viral replication were examined in monocyte-derived DCs-peripheral blood lymphocytes cocultures. The rate of p24 antigen production during the logarithmic phase of viral replication was determined by enzyme-linked immunosorbent assay. Additionally, nef variants were cloned and expressed in trans with a HIV luciferase vector and CCR5-tropic HIV-1 envelope, and infectivity was measured in DC-mediated capture-transfer assays. RESULTS Replication capacity of HIV-1 viral CCR5-tropic isolates in monocyte-derived dendritic cells-peripheral blood lymphocytes cocultures was linearly associated with the plasma viral RNA levels in a cohort of HIV-1-infected individuals exhibiting an inverse relationship between plasma viral RNA and CD4 cell count. Furthermore, infectivity activity of nef variants in context of DC-mediated enhanced infection of T cells also showed a linear relationship to plasma viral RNA levels. CONCLUSIONS These results illustrate that replication capacity of HIV-1 in DC T-cell cultures is a significant determinant of plasma viral RNA level. The data suggest that adaptation of HIV-1 to DC interactions with T cells influences the level of viral replication in the host.
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Martin-Blondel G, Soumah M, Camara B, Chabrol A, Porte L, Delobel P, Cuzin L, Berry A, Massip P, Marchou B. [Impact of malaria on HIV infection]. Med Mal Infect 2009; 40:256-67. [PMID: 19951829 DOI: 10.1016/j.medmal.2009.10.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Revised: 09/15/2009] [Accepted: 10/28/2009] [Indexed: 10/20/2022]
Abstract
Malaria and HIV are two major public health issues, especially in sub-Saharan Africa. HIV infection increases the incidence of clinical malaria, inversely correlated with the degree of immunodepression. The effect of malaria on HIV infection is not as well established. Malaria, when fever and parasitemia are high, may be associated with transient increases in HIV viral load. The effect of subclinical malaria on HIV viral load is uncertain. During pregnancy, placental malaria is associated with higher plasma and placental HIV viral loads, independently of the severity of immunodeficiency. However, the clinical impact of these transient increases of HIV viral load remains unknown. Although some data suggests that malaria might enhance sexual and mother-to-child transmissions, no clinical study has confirmed this. Nevertheless pregnant women and children with malaria-induced anemia are also exposed to HIV through blood transfusions. Integrated HIV and malaria control programs in the regions where both infections overlap are necessary.
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Affiliation(s)
- G Martin-Blondel
- Service des maladies infectieuses et tropicales, hôpital Purpan, place du Docteur-Baylac, TSA 40031, 31059 Toulouse cedex 9, France
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Structural basis of HIV-1 activation by NF-kappaB--a higher-order complex of p50:RelA bound to the HIV-1 LTR. J Mol Biol 2009; 393:98-112. [PMID: 19683540 DOI: 10.1016/j.jmb.2009.08.023] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 08/04/2009] [Accepted: 08/05/2009] [Indexed: 12/22/2022]
Abstract
The activation and latency of human immunodeficiency virus type 1 (HIV-1) are tightly controlled by the transcriptional activity of its long terminal repeat (LTR) region. The LTR is regulated by viral proteins as well as host factors, including the nuclear factor kappaB (NF-kappaB) that becomes activated in virus-infected cells. The two tandem NF-kappaB sites of the LTR are among the most highly conserved sequence elements of the HIV-1 genome. Puzzlingly, these sites are arranged in a manner that seems to preclude simultaneous binding of both sites by NF-kappaB, although previous biochemical work suggests otherwise. Here, we have determined the crystal structure of p50:RelA bound to the tandem kappaB element of the HIV-1 LTR as a dimeric dimer, providing direct structural evidence that NF-kappaB can occupy both sites simultaneously. The two p50:RelA dimers bind the adjacent kappaB sites and interact through a protein contact that is accommodated by DNA bending. The two dimers clamp DNA from opposite faces of the double helix and form a topological trap of the bound DNA. Consistent with these structural features, our biochemical analyses indicate that p50:RelA binds the HIV-1 LTR tandem kappaB sites with an apparent anti-cooperativity but enhanced kinetic stability. The slow on and off rates we observe may be relevant to viral latency because viral activation requires sustained NF-kappaB activation. Furthermore, our work demonstrates that the specific arrangement of the two kappaB sites on the HIV-1 LTR can modulate the assembly kinetics of the higher-order NF-kappaB complex on the viral promoter. This phenomenon is unlikely restricted to the HIV-1 LTR but probably represents a general mechanism for the function of composite DNA elements in transcription.
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Yu L, Mohanram V, Simonson OE, Smith CIE, Spetz AL, Mohamed AJ. Proteasome inhibitors block HIV-1 replication by affecting both cellular and viral targets. Biochem Biophys Res Commun 2009; 385:100-5. [PMID: 19426715 DOI: 10.1016/j.bbrc.2009.04.156] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Accepted: 04/27/2009] [Indexed: 12/17/2022]
Abstract
HIV-1 has proved to be notoriously difficult to tackle despite the availability of more than 20 clinically approved drugs. The majority of these drugs, however, target viral genes and their continued use will select for drug-resistant strains. Since NF-kappaB signaling is critical for viral replication, we wanted to investigate the effect of proteasome inhibitors on viral gene expression. We herein demonstrate that proteasome and NF-kappaB inhibitors effectively shut down transcription from the HIV-1 LTR-promoter. We further show that replication of HIV-1 in PBMC was severely compromised following treatment with proteasome inhibitors alone or in combination with other antiretroviral drugs. Finally, incubation of PBMC with these drugs reduced expression of IL-2 inducible T cell kinase (Itk), a Tec-family kinase, recently shown to be required for HIV-1 replication. These results suggest that proteasome inhibitors suppress LTR-promoter activity by interfering with cellular targets required for viral replication.
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Affiliation(s)
- Liang Yu
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden.
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Biphasic decay kinetics suggest progressive slowing in turnover of latently HIV-1 infected cells during antiretroviral therapy. Retrovirology 2008; 5:107. [PMID: 19036147 PMCID: PMC2630982 DOI: 10.1186/1742-4690-5-107] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Accepted: 11/26/2008] [Indexed: 01/22/2023] Open
Abstract
Background Mathematical models based on kinetics of HIV-1 plasma viremia after initiation of combination antiretroviral therapy (cART) inferred HIV-infected cells to decay exponentially with constant rates correlated to their strength of virus production. To further define in vivo decay kinetics of HIV-1 infected cells experimentally, we assessed infected cell-classes of distinct viral transcriptional activity in peripheral blood mononuclear cells (PBMC) of five patients during 1 year after initiation of cART Results In a novel analytical approach patient-matched PCR for unspliced and multiply spliced viral RNAs was combined with limiting dilution analysis at the single cell level. This revealed that HIV-RNA+ PBMC can be stratified into four distinct viral transcriptional classes. Two overlapping cell-classes of high viral transcriptional activity, suggestive of a virion producing phenotype, rapidly declined to undetectable levels. Two cell classes expressing HIV-RNA at low and intermediate levels, presumably insufficient for virus production and occurring at frequencies exceeding those of productively infected cells matched definitions of HIV-latency. These cells persisted during cART. Nevertheless, during the first four weeks of therapy their kinetics resembled that of productively infected cells. Conclusion We have observed biphasic decays of latently HIV-infected cells of low and intermediate viral transcriptional activity with marked decreases in cell numbers shortly after initiation of therapy and complete persistence in later phases. A similar decay pattern was shared by cells with greatly enhanced viral transcriptional activity which showed a certain grade of levelling off before their disappearance. Thus it is conceivable that turnover/decay rates of HIV-infected PBMC may be intrinsically variable. In particular they might be accelerated by HIV-induced activation and reactivation of the viral life cycle and slowed down by the disappearance of such feedback-loops after initiation of cART.
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Bates DL, Barthel KKB, Wu Y, Kalhor R, Stroud JC, Giffin MJ, Chen L. Crystal structure of NFAT bound to the HIV-1 LTR tandem kappaB enhancer element. Structure 2008; 16:684-94. [PMID: 18462673 DOI: 10.1016/j.str.2008.01.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Revised: 01/24/2008] [Accepted: 01/24/2008] [Indexed: 10/22/2022]
Abstract
The host factor, nuclear factor of activated T-cells (NFAT), regulates the transcription and replication of HIV-1. Here, we have determined the crystal structure of the DNA binding domain of NFAT bound to the HIV-1 long terminal repeat (LTR) tandem kappaB enhancer element at 3.05 A resolution. NFAT binds as a dimer to the upstream kappaB site (Core II), but as a monomer to the 3' end of the downstream kappaB site (Core I). The DNA shows a significant bend near the 5' end of Core I, where a lysine residue from NFAT bound to the 3' end of Core II inserts into the minor groove and seems to cause DNA bases to flip out. Consistent with this structural feature, the 5' end of Core I become hypersensitive to dimethylsulfate in the in vivo footprinting upon transcriptional activation of the HIV-1 LTR. Our studies provide a basis for further investigating the functional mechanisms of NFAT in HIV-1 transcription and replication.
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Affiliation(s)
- Darren L Bates
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO 80309-0215, USA
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Carreño AD, Mergia A, Novak J, Gengozian N, Johnson CM. Loss of naïve (CD45RA+) CD4+ lymphocytes during pediatric infection with feline immunodeficiency virus. Vet Immunol Immunopathol 2008; 121:161-8. [PMID: 17964661 DOI: 10.1016/j.vetimm.2007.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2007] [Revised: 08/14/2007] [Accepted: 09/05/2007] [Indexed: 11/24/2022]
Abstract
Feline immunodeficiency virus (FIV) infection of cats is an animal model for the pathogenesis of CD4+ lymphopenia and thymus dysfunction in HIV-infected humans. Recently, a monoclonal antibody (755) was reported to recognize the feline homologue to CD45RA, allowing the enumeration of naïve T cells in cats. We tested the hypothesis that pediatric FIV infection would be associated with a selective loss of naïve CD4+ lymphocytes by inoculating newborn cats with a pathogenic clone of FIV (JSY3) or a related clone with an inactive ORF-A gene (JSY3-DeltaORFA), and compared the data to age-matched uninfected control cats. Both FIV inocula were associated with a reduction in the CD4-CD8 ratio (p=0.01), which was attributable to a disproportionate loss of naïve CD4+ cells (p=0.01) vs. naïve CD8+ cells. Therefore, the reduced CD4:CD8 ratio in FIV-infected juvenile cats is associated with a selective depletion of naïve CD4+ cells from the blood.
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Affiliation(s)
- Abigail D Carreño
- Department of Pathobiology, Auburn University, Auburn, AL 36849, United States
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Evans VA, Cameron PU, Lewin SR. Human thymic dendritic cells: Regulators of T cell development in health and HIV-1 infection. Clin Immunol 2008; 126:1-12. [DOI: 10.1016/j.clim.2007.08.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2007] [Revised: 08/20/2007] [Accepted: 08/20/2007] [Indexed: 12/12/2022]
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Hsue PY, Hunt PW, Sinclair E, Bredt B, Franklin A, Killian M, Hoh R, Martin JN, McCune JM, Waters DD, Deeks SG. Increased carotid intima-media thickness in HIV patients is associated with increased cytomegalovirus-specific T-cell responses. AIDS 2006; 20:2275-83. [PMID: 17117013 DOI: 10.1097/qad.0b013e3280108704] [Citation(s) in RCA: 213] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES HIV-infected subjects are at increased risk for myocardial infarction. The mechanism of this increased risk remains unclear. Since cytomegalovirus (CMV) infection has been associated with accelerated atherosclerosis in the transplant population and immune responses against CMV may be altered by HIV disease, we hypothesized that enhanced T-cell responses against CMV would be associated with increased atherosclerosis in subjects with HIV. METHODS We measured high-sensitivity C-reactive protein (hs-CRP), T-cell activation, CMV-specific T-cell responses, and carotid artery intima-media thickness (IMT) in 93 HIV-infected subjects and in 37 uninfected controls. RESULTS The mean age of the HIV-infected subjects was 48 years and 85 (91%) were male. The median carotid IMT was higher in the HIV-infected group compared to the uninfected group (0.95 mm versus 0.68 mm, P < 0.001). This difference remained significant after controlling for all traditional risk factors. Compared to HIV-negative controls, HIV-infected subjects had higher median levels of hs-CRP (P = 0.05), higher levels of CD4 and CD8 T-cell activation (P < 0.0001) and higher CMV-specific interferon-gamma CD8 T-cell responses (P < 0.0001). CMV-specific T-cell responses, but not hs-CRP and T-cell activation, were independently associated with higher carotid IMT (P = 0.001). CONCLUSIONS HIV-infected subjects had thicker carotid IMT compared to controls. While HIV patients also had higher T-cell activation, hs-CRP levels, and CMV-specific T-cell responses, only CMV-specific T-cell responses were independently associated with IMT. Accelerated atherosclerosis in HIV patients may be mediated by heightened CMV-induced immune responses.
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Affiliation(s)
- Priscilla Y Hsue
- Divisions of Cardiology, San Francisco General Hospital, University of California, San Francisco, USA.
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Abstract
Although vaccine-preventable diseases are common in HIV, concerns about vaccine safety and lack of efficacy in this patient population often lead to missed opportunities for vaccination. In this article, we review the literature regarding vaccine risks and benefits and offer recommendations regarding their use and timing in patients with HIV infection.
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Affiliation(s)
- Todd D Gleeson
- Department of Infectious Diseases, National Naval Medical Center, 8901 Wisconsin Avenue, Bethesda, MD 20889, USA
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Benito JM, López M, Lozano S, Ballesteros C, Martinez P, González-Lahoz J, Soriano V. Differential Upregulation of CD38 on Different T-Cell Subsets May Influence the Ability to Reconstitute CD4+ T Cells Under Successful Highly Active Antiretroviral Therapy. J Acquir Immune Defic Syndr 2005; 38:373-81. [PMID: 15764953 DOI: 10.1097/01.qai.0000153105.42455.c2] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Immune activation is an independent surrogate marker of CD4 T-cell depletion in HIV-infected patients. Highly active antiretroviral therapy (HAART) reduces disease progression as a direct consequence of suppressing HIV replication. Immune function does not normalize completely in most subjects on HAART, however, perhaps reflecting residual HIV replication. So far, it is unclear to what extent immune activation may influence the evolution of CD4 T-cell counts in patients on HAART. PATIENTS AND METHODS The expression of CD38 on naive and memory subsets of CD4+ and CD8+ T cells was measured quantitatively by flow cytometry in 62 drug-naive HIV-positive and 30 HIV-uninfected controls. In addition, the evolution of this marker as well as that of some virologic parameters (plasma viremia and proviral load) and CD4 counts were assessed in 25 HIV-infected individuals who initiated HAART and were followed for 12 months. RESULTS The mean level of CD38 on memory CD4+ and CD8+ T cells as well as in naive CD8+ cells was significantly higher in drug-naive HIV-positive subjects than in HIV-negative controls. Moreover, it was highly correlated with viral load titers. In patients on successful HAART, immune activation declined in all T-cell subsets, particularly among memory CD8+ cells. It remained elevated with respect to HIV-negative controls, however, even after 12 months of HAART. There was a significant correlation between the CD8+ T-cell activation decay and the increase of CD4+ T cells on HAART. Patients with the highest decline in CD8 activation were those showing the highest CD4 T-cell gains after 12 months of therapy. CONCLUSIONS The level of CD38 expression on different T-cell subsets is differentially upregulated in drug-naive HIV-infected patients. After successful HAART, immune activation decreases in all T-cell subsets, although it still remains elevated in most cases after 12 months of HAART. The extent of immune deactivation under successful HAART correlates with the ability to reconstitute CD4 counts.
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Mermin J, Lule J, Ekwaru JP, Malamba S, Downing R, Ransom R, Kaharuza F, Culver D, Kizito F, Bunnell R, Kigozi A, Nakanjako D, Wafula W, Quick R. Effect of co-trimoxazole prophylaxis on morbidity, mortality, CD4-cell count, and viral load in HIV infection in rural Uganda. Lancet 2004; 364:1428-34. [PMID: 15488218 DOI: 10.1016/s0140-6736(04)17225-5] [Citation(s) in RCA: 258] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Prophylaxis with co-trimoxazole (trimethoprim-sulphamethoxazole) is recommended for people with HIV infection or AIDS but is rarely used in Africa. We assessed the effect of such prophylaxis on morbidity, mortality, CD4-cell count, and viral load among people with HIV infection living in rural Uganda, an area with high rates of bacterial resistance to co-trimoxazole. METHODS Between April, 2001, and March, 2003, we enrolled, and followed up with weekly home visits, 509 individuals with HIV-1 infection and their 1522 HIV-negative household members. After 5 months of follow-up, HIV-positive participants were offered daily co-trimoxazole prophylaxis (800 mg trimethoprim, 160 mg sulphamethoxazole) and followed up for a further 1.5 years. We assessed rates of malaria, diarrhoea, hospital admission, and death. FINDINGS Co-trimoxazole was well tolerated with rare (<2% per person-year) adverse reactions. Even though rates of resistance in diarrhoeal pathogens were high (76%), co-trimoxazole prophylaxis was associated with a 46% reduction in mortality (hazard ratio 0.54 [95% CI 0.35-0.84], p=0.006) and lower rates of malaria (multivariate incidence rate ratio 0.28 [0.19-0.40], p<0.0001), diarrhoea (0.65 [0.53-0.81], p<0.0001), and hospital admission (0.69 [0.48-0.98], p=0.04). The annual rate of decline in CD4-cell count was less during prophylaxis than before (77 vs 203 cells per microL, p<0.0001), and the annual rate of increase in viral load was lower (0.08 vs 0.90 log(10) copies per mL, p=0.01). INTERPRETATION Daily co-trimoxazole prophylaxis was associated with reduced morbidity and mortality and had beneficial effects on CD4-cell count and viral load. Co-trimoxazole prophylaxis is a readily available, effective intervention for people with HIV infection in Africa.
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Affiliation(s)
- Jonathan Mermin
- CDC-Uganda, Global AIDS Program, National Center for HIV, STD and TB Prevention, National Center for Infectious Diseases; Centers for Disease Control and Prevention, Atlanta, GA, USA.
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Kimata JT, Wilson JM, Patel PG. The increased replicative capacity of a late-stage simian immunodeficiency virus mne variant is evident in macrophage- or dendritic cell-T-cell cocultures. Virology 2004; 327:307-17. [PMID: 15351218 DOI: 10.1016/j.virol.2004.07.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2004] [Revised: 06/10/2004] [Accepted: 07/13/2004] [Indexed: 10/26/2022]
Abstract
Human and simian immunodeficiency virus (HIV and SIV) may co-opt antigen capture and presentation functions of antigen presenting cells (APCs) to facilitate infection of CD4+ T-cells. To address whether the replicative capacity of SIV in the host may be associated with the extent of viral replication in response to APC-T-cell interactions, we compared the replicative phenotypes of cloned early and late-stage SIVmne variants of known pathogenicity. Here, we show that the highly pathogenic late variant SIVmne027 replicates more efficiently in both macrophage- and dendritic cell (DC)-T-cell cocultures than the minimally pathogenic early virus SIVmneCl8. Contact between either macrophages or DC and T-cells increases replication of SIVmne027. Our analysis also demonstrates that mutations in pol and nef contribute to the greater replicative capacity of SIVmne027 in DC- or macrophage-T-cell cocultures. Together, these data suggest that variant viruses that evolve to replicate vigorously in response to APC-T-cell interactions may have increased replicative capacity in vivo.
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Affiliation(s)
- Jason T Kimata
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA
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van Asten L, Danisman F, Otto SA, Borghans JAM, Hazenberg MD, Coutinho RA, Prins M, Miedema F. Pre-seroconversion immune status predicts the rate of CD4 T cell decline following HIV infection. AIDS 2004; 18:1885-93. [PMID: 15353974 DOI: 10.1097/00002030-200409240-00004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To study whether immune status prior to HIV seroconversion predicts CD4 T cell decline during HIV infection. DESIGN Prospective cohort study including 51 injecting drug users (IDU) who were HIV negative at study entry and seroconverted for HIV during follow-up. METHODS Cryopreserved peripheral blood mononuclear cells obtained before HIV seroconversion were used to measure naive (CD45RO-CD27+), memory (CD45RO+CD27+), and total CD4 T cell numbers, the fraction of dividing Ki67+CD4+ T cells, and CD4 T cell receptor excision circles (TREC). The effect of pre-seroconversion immune status, as defined by these markers, on the rate of CD4 T cell decline during HIV infection was assessed using linear regression for repeated measurements. RESULTS IDU with low pre-seroconversion CD4 T cell TREC contents lost CD4 T cells at a significantly faster rate during HIV infection than those with a high CD4 T cell TREC content. IDU with higher pre-seroconversion CD4 T cell numbers had a significantly steeper CD4 T cell decline in the first 3 months of HIV infection, but their CD4 T cell counts remained higher throughout HIV infection. Intermediate levels of pre-seroconversion dividing Ki67+CD4+ T cells were associated with a significantly steeper CD4 cell decline than high levels. IDU with the highest pre-seroconversion drug-injecting frequencies showed slower CD4 T cell decline than those who injected less. No correlation was present between pre-seroconversion immune markers and the pre-seroconversion duration or intensity of drug use. CONCLUSION Among IDU, immune status prior to HIV infection as measured by TREC content affects the disease course after HIV seroconversion.
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Affiliation(s)
- Liselotte van Asten
- Municipal Health Service, Sanquin Research at CLB and Academic Medical Centre and the Department of Human Retrovirology, Academic Medical Centre, Amsterdam, the Netherlands
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Shinya E, Owaki A, Shimizu M, Takeuchi J, Kawashima T, Hidaka C, Satomi M, Watari E, Sugita M, Takahashi H. Endogenously expressed HIV-1 nef down-regulates antigen-presenting molecules, not only class I MHC but also CD1a, in immature dendritic cells. Virology 2004; 326:79-89. [PMID: 15262497 DOI: 10.1016/j.virol.2004.06.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2004] [Accepted: 06/02/2004] [Indexed: 01/30/2023]
Abstract
The effects of Nef molecules on immature dendritic cells (iDCs) were analyzed using recombinant human immunodeficiency virus type 1 (HIV-1) with intact nef gene, pseudotyped with vesicular stomatitis virus glycoprotein, HIV/VSV-G/+Nef. When iDCs were infected with HIV/VSV-G/+Nef, the surface expression of CD1a, a molecule for presenting glycolipid/lipid antigens, was selectively down-regulated among CD1 molecules (CD1a, -b, -c, and -d) as well as class I MHC. Moreover, the CD1a molecules were also down-modulated and co-localized with DsRed2-tagged-Nef in CD1a-transfected cells. Their co-localization was dependent upon CD1a cytoplasmic tail and the CD1a was redistributed from cell surface to LAMP-1+ late endosomal/lysosomal compartment. These findings reveal that the HIV-1-Nef interferes with the intracellular trafficking of CD1a, and suggest the involvement of CD1a-restricted immune effectors in the protective immunity against HIV-1 infection, which implicates the feasibility of virus-derived glycolipid/lipid antigens together with epitope peptides for the vaccine development.
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Affiliation(s)
- Eiji Shinya
- Department of Microbiology and Immunology, Nippon Medical School, Bunkyo, Tokyo 113-8602, Japan
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Fincham JE, Markus MB, Adams VJ. Could control of soil-transmitted helminthic infection influence the HIV/AIDS pandemic. Acta Trop 2003; 86:315-33. [PMID: 12745148 DOI: 10.1016/s0001-706x(03)00063-9] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In May 2001, the World Health Assembly (WHA) estimated that two billion people were infected by soil-transmitted helminths (S-THs) and schistosomiasis, worldwide. The WHA urged member states to recognise that there can be synergy between public health control programmes for S-THs, schistosomiasis and other diseases. This is particularly relevant to the new dimension created by the HIV/AIDS epidemics in the same impoverished communities and countries where helminthiasis is hyperendemic. Immunological adaptation between humans and parasitic helminths has developed during evolution. Review of 109 research papers, 76% (83/109) of which, were published between 1995 and February 2002, revealed increasing evidence that this relationship may have created an opportunity for more rapid infection by the human immunodeficiency virus (HIV), as well as quicker progression to AIDS. Moreover, the efficacy of some vaccines against HIV is likely to be impaired by chronic helminthiasis. For this, there is strong, indirect evidence. There is an urgent need for parasitologists, epidemiologists, immunologists and virologists to undertake comprehensive, transdisciplinary research. On the other hand, there is no current evidence that immunosuppression by HIV facilitates helminthic infection. The situation in regard to strongyloidiasis, however, is not yet clear.
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Affiliation(s)
- John E Fincham
- Amoebiasis Research Unit, Infection and Immunity Programme, South African Medical Research Council, PO Box 19070, Tygerberg 7505, South Africa.
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Rowland-Jones SL. Timeline: AIDS pathogenesis: what have two decades of HIV research taught us? Nat Rev Immunol 2003; 3:343-8. [PMID: 12669024 DOI: 10.1038/nri1058] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
22 years ago, the first cases of an acquired immunodeficiency syndrome afflicting young, homosexual American men were reported, heralding what we now know to be the beginning of the HIV epidemic. Since then, billions of US dollars have been invested in HIV research in the hope of gaining a better understanding of this infection and how to prevent and treat it. What are the landmarks in HIV research over the past two decades, and what questions still remain to be answered? What has the intense study of HIV infection taught us about other virus infections and how our immune system responds to them?
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Affiliation(s)
- Sarah L Rowland-Jones
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford OX3 0DW, UK.
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Jones LE, Perelson AS. Modeling the effects of vaccination on chronically infected HIV-positive patients. J Acquir Immune Defic Syndr 2002; 31:369-77. [PMID: 12447006 DOI: 10.1097/00126334-200212010-00001] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
T-cell activation plays a critical role in the initiation and propagation of HIV-1 infection and yet transient activation of the immune system is a normal response to immunization. While it is now considered wise to vaccinate HIV-1-positive patients, it is crucial to anticipate any lasting effects of vaccination on plasma HIV-1 RNA levels and on infected T-cell populations. We extend a simple dynamic model of HIV infection to include T-cell activation by vaccination. We show that the model can reproduce many but not all of the features of the post-tetanus immunization rise in viral load observed and reported on by Stanley et al. in 1966 ( 334:1222-1230). Amplitudes and approximate timing of postimmunization peak viral loads were matched in 10 of 12 cases; in patients with double postimmunization peaks of nearly equal amplitude the later peaks were matched. Furthermore, our simulations suggest that productively infected cell populations track postvaccination increases in plasma viral load, rising and falling in concert over a period of about 4 weeks, whereas chronically infected cells peak later and remain elevated over baseline levels for up to 6 weeks postvaccination.
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Affiliation(s)
- Laura E Jones
- Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, USA
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Rowland-Jones SL, Lohman B. Interactions between malaria and HIV infection-an emerging public health problem? Microbes Infect 2002; 4:1265-70. [PMID: 12467769 DOI: 10.1016/s1286-4579(02)01655-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recent evidence demonstrates interactions between malaria and HIV infection. HIV-infected people are more likely to experience clinical malaria, and acute malaria can up-regulate HIV replication, leading to higher plasma viral loads. This is most serious in pregnant women, where HIV infection increases the risk of placental malaria, leading to increased infant morbidity and mortality.
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Affiliation(s)
- Sarah L Rowland-Jones
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, OX3 0DW, Oxford, UK.
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Seage GR, Losina E, Goldie SJ, Paltiel AD, Kimmel AD, Freedberg KA. The relationship of preventable opportunistic infections, HIV-1 RNA, and CD4 Cell counts to chronic mortality. J Acquir Immune Defic Syndr 2002; 30:421-8. [PMID: 12138349 DOI: 10.1097/00042560-200208010-00008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Both HIV-1 RNA and absolute CD4 cell counts have been identified as important predictors of HIV-1 disease progression and mortality. The independent impact of opportunistic infections on the risk of chronic mortality, defined as death beyond 30 days of an opportunistic infection, has not been studied when controlling for HIV-1 RNA. Our objective was to determine the relationship between a history of any of five preventable opportunistic infections (Pneumocystis carinii pneumonia, Mycobacterium avium complex, toxoplasmosis, cytomegalovirus, and candida esophagitis) and chronic mortality. METHODS Using the Multicenter AIDS Cohort Study (MACS) public use data set of 2193 HIV-infected men in four U.S. cities, we employed a Cox regression model to estimate the impact of a history of preventable opportunistic infection on chronic mortality while controlling for maximum HIV-1 RNA, CD4 cell count, use of antiretroviral drugs, and age. FINDINGS The chronic mortality rate among individuals with a history of preventable opportunistic infection was 66.7 per 100 person-years compared with 2.3 per 100 person-years for those without a history of preventable opportunistic infection (RR = 28.4, 95% CI: 24.7-32.8). In the adjusted analysis, the relative hazard of death for those with a history of preventable opportunistic infections was 7.0 (5.8-8.3), whereas antiretroviral therapy was associated with a decreased risk of death (0.37 [0.30-0.44]). We found no association between maximum HIV-1 RNA and chronic mortality. There was statistically significant effect modification between preventable opportunistic infections and CD4 cell count (p <.0001). INTERPRETATION Preventable opportunistic infections cause not only short-term mortality in HIV-1 disease but appear to have a major impact on chronic mortality.
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Affiliation(s)
- George R Seage
- Department of Epidemiology and Center for Risk Analysis, Department of Health Policy and Management, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
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Piguet V, Blauvelt A. Essential roles for dendritic cells in the pathogenesis and potential treatment of HIV disease. J Invest Dermatol 2002; 119:365-9. [PMID: 12190858 DOI: 10.1046/j.1523-1747.2002.01840.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
During sexual transmission of HIV, virus crosses mucosal epithelium and eventually reaches lymphoid tissue where it establishes a permanent infection. Evidence has accumulated that infection of Langerhans cells, which are resident dendritic cells in pluristratified epithelia, plays a crucial role in the early events of HIV transmission. HIV infection of Langerhans cells is regulated by surface expression of CD4 and CCR5. Thus, topical microbicides that interfere with HIV infection of Langerhans cells represent an attractive strategy for blocking sexual transmission of virus. Capture and uptake of HIV virions is another major pathway by which HIV interacts with dendritic cells. By contrast, this process is mediated by a newly described C-type lectin, DC-SIGN. It is well established that HIV-exposed dendritic cells transmit virus efficiently to cocultured T cells. Indeed, dendritic cell-T cell interaction, critical in the generation of immune responses, is a rich microenvironment for HIV replication both in vitro and in vivo. Dendritic cells that have captured virus via DC-SIGN, and not HIV-infected dendritic cells, probably facilitate most infection of T cells in chronically infected individuals. Therefore, blocking DC-SIGN-mediated capture of HIV represents a potential therapeutic antiviral strategy for HIV disease. Lastly, dendritic cells have been targeted both ex vivo and in vivo to initiate and enhance HIV-specific immunity. Although these approaches are promising for both therapeutic and prophylactic vaccines, much additional work is needed in order to optimize dendritic-cell-based immunization strategies.
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Affiliation(s)
- Vincent Piguet
- Department of Dermatology, University Hospital of Geneva, Switzerland; Dermatology Branch, National Cancer Institute, Bethesda, Maryland , USA.
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35
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Jameson B, Baribaud F, Pöhlmann S, Ghavimi D, Mortari F, Doms RW, Iwasaki A. Expression of DC-SIGN by dendritic cells of intestinal and genital mucosae in humans and rhesus macaques. J Virol 2002; 76:1866-75. [PMID: 11799181 PMCID: PMC135921 DOI: 10.1128/jvi.76.4.1866-1875.2002] [Citation(s) in RCA: 211] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
To better understand the role of dendritic cells (DCs) in human immunodeficiency virus (HIV) transmission at mucosal surfaces, we examined the expressions of the HIV adhesion molecule, dendritic-cell-specific ICAM-3 grabbing nonintegrin (DC-SIGN), its closely related homologue DC-SIGNR, and HIV coreceptors by distinct DC populations in the intestinal and genital tracts of humans and rhesus macaques. We also developed monoclonal antibodies (MAbs) specific for DC-SIGN or DC-SIGNR. In the Peyer's patches, DC-SIGN expression was detected in the interfollicular regions and in clusters of cells in the subepithelial dome regions. DC-SIGN expression was not found on plasmacytoid DCs. DC-SIGNR expression was restricted to endothelial cells in approximately one-third of the capillaries in the terminal ileum. In the vaginal epithelium, Langerhans' cells did not express DC-SIGN, whereas subepithelial DCs in the lamina propria expressed moderate levels of DC-SIGN. Finally, the rectum contained cells that expressed high levels of DC-SIGN throughout the entire thickness of the mucosa, while solitary lymphoid nodules within the rectum showed very little staining for DC-SIGN. Triple-color analysis of rectal tissue indicated that CCR5(+) CD4(+) DC-SIGN(+) DCs were localized just beneath the luminal epithelium. These findings suggest that DC-SIGN(+) DCs could play a role in the transmission of primate lentiviruses in the ileum and the rectum whereas accessibility to DC-SIGN(+) cells is limited in an intact vaginal mucosa. Finally, we identified a MAb that blocked simian immunodeficiency virus interactions with rhesus macaque DC-SIGN. This and other specific MAbs may be used to assess the relevance of DC-SIGN in virus transmission in vivo.
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Affiliation(s)
- Brian Jameson
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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36
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Francesconi P, Fabiani M, Dente MG, Lukwiya M, Okwey R, Ouma J, Ochakachon R, Cian F, Declich S. HIV, malaria parasites, and acute febrile episodes in Ugandan adults: a case-control study. AIDS 2001; 15:2445-50. [PMID: 11740196 DOI: 10.1097/00002030-200112070-00013] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND In sub-Saharan Africa, co-infection with HIV and malaria is probably very common. Although an interaction between the two infections is biologically plausible, it has not been investigated thoroughly. OBJECTIVES To evaluate the association firstly between co-infection with HIV and malaria parasites and the occurrence of acute fever, and secondly between HIV infection and clinical malaria, defined as the presence of acute fever and malaria parasites. METHODS A hospital-based case-control study was conducted in Gulu District (northern Uganda), an area endemic for malaria and with a high HIV prevalence. HIV testing and malaria parasite quantification were performed on 167 consecutive adult out-patients with acute fever and no signs or symptoms of localized infection, and on 134 consecutive adult in-patients without fever who were admitted for non-HIV-related trauma or elective surgery. RESULTS No significant association with acute fever was observed for single infection with either malaria parasites [adjusted odds ratio (AOR), 1.75; 95% confidence interval (CI), 0.73-4.21] or HIV (AOR, 1.01; 95% CI, 0.51-2.03), whereas a significant association was observed for co-infection (AOR, 9.75; 95% CI, 1.19-80.00). An association was found between HIV infection and clinical malaria (AOR, 2.34; 95% CI, 0.89-6.17); the association became statistically significant when the definition of clinical malaria included a cut-off for parasite density (50th percentile; i.e., 586 parasites/microl; AOR, 3.61; 95% CI, 1.04-12.52). CONCLUSIONS Despite the limited statistical power, the results of our study show an association between HIV infection and clinical malaria; if confirmed, this finding could be important for public health in sub-Saharan Africa.
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Affiliation(s)
- P Francesconi
- Laboratory of Epidemiology and Biostatistics, Istituto Superiore di Sanità, Rome, Italy
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37
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Gruber A, Lell CP, Speth C, Stoiber H, Lass-Flörl C, Sonneborn A, Ernst JF, Dierich MP, Würzner R. Human immunodeficiency virus type 1 Tat binds to Candida albicans, inducing hyphae but augmenting phagocytosis in vitro. Immunology 2001; 104:455-61. [PMID: 11899432 PMCID: PMC1783331 DOI: 10.1046/j.1365-2567.2001.01328.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tat, the human immunodeficiency virus type 1 (HIV-1) transactivating protein, binds through its RGD-motif to human integrin receptors. Candida albicans, the commonest cause of mucosal candidiasis in subjects infected with HIV-1, also possesses RGD-binding capacity. The present study reveals that Tat binds to C. albicans but not to C. tropicalis. Tat binding was markedly reduced by laminin and to a lesser extent by a complement C3 peptide containing the RGD motif, but not by a control peptide. The outgrowth of C. albicans was accelerated following binding of Tat, but phagocytosis of opsonized C. albicans was also increased after Tat binding. Thus, Tat binding promotes fungal virulence by inducing hyphae but may also reduce it by augmenting phagocytosis. The net effect of Tat in vivo is difficult to judge but in view of the many disease-promoting effects of Tat we propose that accelerating the formation of hyphae dominates over the augmentation of phagocytosis.
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Affiliation(s)
- A Gruber
- Institute for Hygiene and Social Medicine, University of Innsbruck, Ludwig Boltzmann-Institute for AIDS-Research, Innsbruck, Austria.
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Abstract
The human immunodeficiency virus-1 (HIV-1), the cause of AIDS, remains a significant cause of morbidity and mortality throughout the planet. Although reverse transcriptase and protease inhibitors have substantially slowed the virus, viral resistance complicates therapy. Because HIV-1 relies on its host's transcriptional machinery for its own replication, strategies for targeting activation-dependent transcription factors in CD4 T cells are being considered for adjunctive therapy in HIV-1-infected individuals. The nuclear factor of activated T cells (NFAT) family of transcription factors is one such target. On T-cell stimulation, NFAT proteins translocate to the nucleus, where they activate a large number of early response genes, including cytokines such as interleukin-2. Activation and nuclear translocation of NFAT proteins are abrogated by the powerful immunosuppressants cyclosporin A (CsA) and FK506. Over the last several years, various investigators have demonstrated that NFAT proteins bind to the HIV-1 LTR promoter and increase viral transcription. In this report, further evidence supporting a role for NFAT proteins in augmenting HIV-1 transcription is presented. In addition, other mechanisms of HIV-1 inhibition by CsA are reviewed, and the rationale for the use of CsA to treat AIDS is discussed.
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Affiliation(s)
- R Q Cron
- Division of Rheumatology, The Children's Hospital of Philadelphia, Department of Pediatrics, University of Pennsylvania, Philadelphia 19104, USA.
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Lawn SD, Butera ST, Folks TM. Contribution of immune activation to the pathogenesis and transmission of human immunodeficiency virus type 1 infection. Clin Microbiol Rev 2001; 14:753-77, table of contents. [PMID: 11585784 PMCID: PMC89002 DOI: 10.1128/cmr.14.4.753-777.2001] [Citation(s) in RCA: 207] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The life cycle of human immunodeficiency virus type 1 (HIV-1) is intricately related to the activation state of the host cells supporting viral replication. Although cellular activation is essential to mount an effective host immune response to invading pathogens, paradoxically the marked systemic immune activation that accompanies HIV-1 infection in vivo may play an important role in sustaining phenomenal rates of HIV-1 replication in infected persons. Moreover, by inducing CD4+ cell loss by apoptosis, immune activation may further be central to the increased rate of CD4+ cell turnover and eventual development of CD4+ lymphocytopenia. In addition to HIV-1-induced immune activation, exogenous immune stimuli such as opportunistic infections may further impact the rate of HIV-1 replication systemically or at localized anatomical sites. Such stimuli may also lead to genotypic and phenotypic changes in the virus pool. Together, these various immunological effects on the biology of HIV-1 may potentially enhance disease progression in HIV-infected persons and may ultimately outweigh the beneficial aspects of antiviral immune responses. This may be particularly important for those living in developing countries, where there is little or no access to antiretroviral drugs and where frequent exposure to pathogenic organisms sustains a chronically heightened state of immune activation. Moreover, immune activation associated with sexually transmitted diseases, chorioamnionitis, and mastitis may have important local effects on HIV-1 replication that may increase the risk of sexual or mother-to-child transmission of HIV-1. The aim of this paper is to provide a broad review of the interrelationship between immune activation and the immunopathogenesis, transmission, progression, and treatment of HIV-1 infection in vivo.
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Affiliation(s)
- S D Lawn
- HIV and Retrovirology Branch, Division of AIDS, STD, and TB Laboratory Research, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Services, Atlanta, Georgia, USA.
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40
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Scales D, Ni H, Shaheen F, Capodici J, Cannon G, Weissman D. Nonproliferating bystander CD4+ T cells lacking activation markers support HIV replication during immune activation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:6437-43. [PMID: 11342670 DOI: 10.4049/jimmunol.166.10.6437] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
HIV replicates primarily in lymphoid tissue and immune activation is a major stimulus in vivo. To determine the cells responsible for HIV replication during Ag-driven T cell activation, we used a novel in vitro model employing dendritic cell presentation of superantigen to CD4(+) T cells. Dendritic cells and CD4(+) T cells are the major constituents of the paracortical region of lymphoid organs, the main site of Ag-specific activation and HIV replication. Unexpectedly, replication occurred in nonproliferating bystander CD4(+) T cells that lacked activation markers. In contrast, activated Ag-specific cells were relatively protected from infection, which was associated with CCR5 and CXC chemokine receptor 4 down-regulation. The finding that HIV replication is not restricted to highly activated Ag-specific CD4(+) T cells has implications for therapy, efforts to eradicate viral reservoirs, immune control of HIV, and Ag-specific immune defects.
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Affiliation(s)
- D Scales
- Division of Infectious Diseases and Center for AIDS Research, University of Pennsylvania, Philadelphia, PA 19104, USA
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Greenway AL, Holloway G, McPhee DA. HIV-1 Nef: a critical factor in viral-induced pathogenesis. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2001; 48:299-343. [PMID: 10987095 DOI: 10.1016/s1054-3589(00)48010-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- A L Greenway
- AIDS Cellular Biology Unit, Macfarlane Burnet Centre for Medical Research, Fairfield, Victoria, Australia
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David SA, Smith MS, Lopez GJ, Adany I, Mukherjee S, Buch S, Goodenow MM, Narayan O. Selective transmission of R5-tropic HIV type 1 from dendritic cells to resting CD4+ T cells. AIDS Res Hum Retroviruses 2001; 17:59-68. [PMID: 11177384 DOI: 10.1089/088922201750056799] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In an in vitro coculture model of monocyte-derived, cultured human dendritic cells (DC) with autologous CD4(+) resting T cells, CCR5 (R5)-tropic strains of HIV-1, but not CXCR4 (X4)-tropic strains, were transmitted to resting CD4+ T cells, leading to prolific viral output, although DC were susceptible to infection with either strain. Macrophages, which were also infectable with either R5- or X4-tropic strains, did not transmit infection to CD4+ cells. Highly productive HIV infection in this model appeared to be a consequence of heterokaryotic syncytium formation between infected DC and T cells since syncytia formation developed only in R5-infected DC/CD4+ cocultures. These results suggested that the unique microenvironment derived from the fusion between the infected DC and CD4+ cell was highly permissive and selective for replication of R5-tropic viruses. The apparent selectivity for R5-tropic strains in such syncytia was attributable neither to differential DC-mediated activation nor to selective modulation of induction of alpha- or beta-chemokines in the infected DC. This model of HIV replication may provide useful insights into in vitro correlates of HIV pathogenicity.
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Affiliation(s)
- S A David
- Merrell Dow Laboratory of Viral Pathogenesis Department of Microbiology, Immunology, and Molecular Genetics, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA.
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Vanham G, Penne L, Allemeersch H, Kestens L, Willems B, van der Groen G, Jeang KT, Toossi Z, Rich E. Modeling HIV transfer between dendritic cells and T cells: importance of HIV phenotype, dendritic cell-T cell contact and T-cell activation. AIDS 2000; 14:2299-311. [PMID: 11089618 DOI: 10.1097/00002030-200010200-00011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To study the requirements for HIV transfer between dendritic cells (DC) and CD4 T cells, using an in vitro model, combined with flow cytometry. METHODS Immature DC and macrophages (MA) were generated from monocytes. After infection, DC or MA were cultured alone or with purified CD4 T cells. Intracellular HIV was measured, using (1) the monocyte (MO)-tropic AD8 HIV, endowed with enhanced green fluorescent protein (EGFP); and (2) intracellular staining of laboratory HIV strains and clones from primary isolates. RESULTS (1) Clone AD8-EGFP infected DC and MA with equal efficiency, but the virus was preferentially transferred from DC to autologous T cells. (2) DC were more productively infected with R5/NSI, as compared to X4/SI, HIV, but both HIV phenotypes were easily transmitted to autologous T4 cells. (3) HIV-infected DC transferred the virus to T cells across a semi-permeable membrane, if the T cells were in contact with non-infected DC. (4) Co-culture of T cells with autologous non-infected DC induced T-cell activation. HIV-infected DC selectively increased HLA-DR on T cells and HLA-DR (+) T cells were preferential targets for HIV transfer. (5) Resting Ba-L-infected CD4 T cells were able to transmit the virus 'inversely' to co-cultured DC. CONCLUSION HIV transfer between monocyte-derived dendritic cells and autologous CD4 T cells was directly demonstrated using flow cytometry. The transfer proceeded in both directions, depended on cellular contact and was associated with partial T-cell activation. This model, representing relevant in vivo targets of HIV, is useful to further investigate interactions between HIV, DC and T cells, without the need for primary ex vivo DC.
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Affiliation(s)
- G Vanham
- Department of Microbiology, Institute of Tropical Medicine, Antwerp, Belgium.
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Saifuddin M, Spear GT, Chang C, Roebuck KA. Expression of MHC class II in T cells is associated with increased HIV-1 expression. Clin Exp Immunol 2000; 121:324-31. [PMID: 10931149 PMCID: PMC1905707 DOI: 10.1046/j.1365-2249.2000.01290.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
HIV-1 replicates in activated T cells at significantly higher levels than in resting cells. Thus, certain molecules up-regulated during T cell activation appear to be important for HIV-1 replication. In this study, we present evidence suggesting that expression of MHC class II (class II) molecules on CD4+ T cells facilitate HIV-1 replication. T cells that expressed class II supported greater virus replication than T cells lacking class II. The class II+ cells, when either infected with HIV-1 or transfected with an env-minus HIV-1 provirus plasmid, produced 10-20-fold greater virus expression than class II- cells. Anti-class II antibody markedly inhibited virus expression in class II+ cells (but not class II- cells) and also decreased the nuclear binding activity of AP-1, an inducible transcription factor important in T cell activation and HIV-1 expression. Most importantly, the induction of class II expression by transfection of the MHC class II transactivator (CIITA) stimulated HIV-1 replication in Jurkat T cells. Taken together, these data suggest that expression of MHC class II molecules and/or CIITA in T cells enhances HIV-1 transcription.
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Affiliation(s)
- M Saifuddin
- Department of Immunology/Microbiology, Rush University, Chicago, IL, USA.
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45
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Riley JL, Schlienger K, Blair PJ, Carreno B, Craighead N, Kim D, Carroll RG, June CH. Modulation of susceptibility to HIV-1 infection by the cytotoxic T lymphocyte antigen 4 costimulatory molecule. J Exp Med 2000; 191:1987-97. [PMID: 10839813 PMCID: PMC2213525 DOI: 10.1084/jem.191.11.1987] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
CD4 T cells activated in vitro by anti-CD3/28-coated beads are resistant to infection by CC chemokine receptor 5 (CCR5)-dependent HIV-1 isolates. In vivo, antigen-presenting cells (APCs) activate CD4 T cells in part by signaling through the T cell receptor and CD28, yet cells stimulated in this manner are susceptible to HIV-1 infection. We show that cytotoxic T lymphocyte antigen 4 (CTLA-4) engagement counteracts the CD28 antiviral effects, and that the ratio of CTLA-4 to CD28 engagement determines the susceptibility of HIV-1 infection. Furthermore, unopposed CTLA-4 signaling provided by CD28 blockade promotes vigorous HIV-1 replication, despite minimal T cell proliferation. Finally, CTLA-4 antibodies decrease the susceptibility of antigen-activated CD4 T cells to HIV, suggesting a potential approach to prevent or limit viral spread in HIV-1-infected individuals.
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Affiliation(s)
- James L. Riley
- Department of Molecular and Cellular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Katia Schlienger
- Department of Molecular and Cellular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Patrick J. Blair
- Transplant and Autoimmunity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20889
| | - Beatriz Carreno
- Genetics Institute, Incorporated, Cambridge, Massachusetts 02140
| | - Nancy Craighead
- Transplant and Autoimmunity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20889
| | - Daniel Kim
- Division of Retrovirology, Walter Reed Army Institute of Research and Henry M. Jackson Foundation, Rockville, Maryland 20850
| | - Richard G. Carroll
- Department of Molecular and Cellular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Carl H. June
- Department of Molecular and Cellular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104
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Abstract
Nearly 20 years into the HIV pandemic, vaccination of HIV-infected persons remains controversial. Although vaccine-preventable diseases are common in HIV, concerns about vaccine safety and lack of efficacy in this setting often lead to missed opportunities for vaccination. In this article, we review the literature regarding vaccine risks and benefits and offer recommendations regarding their use and timing in HIV-infected persons.
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Treitinger A, Spada C, Verdi JC, Miranda AF, Oliveira OV, Silveira MV, Moriel P, Abdalla DS. Decreased antioxidant defence in individuals infected by the human immunodeficiency virus. Eur J Clin Invest 2000; 30:454-9. [PMID: 10809906 DOI: 10.1046/j.1365-2362.2000.00642.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND The oxidative stress associated with HIV infection may be important for the progression of the disease because reactive oxygen species activate the nuclear transcription factor NF-kappaB, which is obligatory for HIV replication. PATIENTS AND METHODS The activities of the antioxidant enzymes superoxide dismutase (SOD, EC 1.15.1.1) and glutathione peroxidase (GPx, EC 1.11.1.9) of blood plasma and peripheral blood mononuclear cells, as well as the plasma levels of ascorbate, alpha-tocopherol and beta-carotene, were measured in 75 subjects with HIV infection and in 26 controls. The HIV-infected patients were classified according to the Walter Reed Army Institute criteria. RESULTS The extracellular SOD (EC-SOD) of blood plasma activity was decreased in HIV-infected patients compared to controls, while the SOD activity of mononuclear cells decreased with the HIV-associated disease progression. GPx activities and alpha-tocopherol concentration of HIV-infected patients neither differed as compared to controls nor in relation to disease progression. Lower concentrations of ascorbate and beta-carotene were found in HIV-infected patients than in controls. A positive correlation between CD4 lymphocyte counts and the SOD activities of plasma and mononuclear cells was found. CONCLUSION These results suggest that abnormalities of antioxidant defence, mainly of SOD activity, are related to the progression of the HIV infection.
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Vanham G, van Tendeloo V, Willems B, Penne L, Kestens L, Beirnaert E, Fransen K, Heyndrickx L, Zhong P, Davis D, Berneman Z, van der Groen G, Van Bockstaele D. The HIV-2 genotype and the HIV-1 syncytium-inducing phenotype are associated with a lower virus replication in dendritic cells. J Med Virol 2000. [DOI: 10.1002/(sici)1096-9071(200003)60:3<300::aid-jmv9>3.0.co;2-g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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49
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Cron RQ, Bartz SR, Clausell A, Bort SJ, Klebanoff SJ, Lewis DB. NFAT1 enhances HIV-1 gene expression in primary human CD4 T cells. Clin Immunol 2000; 94:179-91. [PMID: 10692237 DOI: 10.1006/clim.1999.4831] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cyclosporin A (CsA) is a potent inhibitor of the NFAT family of transcription factors that enhance T cell activation. The observation that human immunodeficiency virus type 1 (HIV-1)-positive transplant recipients have a reduced HIV-1 viral burden during treatment with CsA suggested that NFAT may play a direct role in enhancing transcription of the HIV-1 viral genome. Two sets of NFAT binding sites were identified in the HIV-1 long terminal repeat (LTR) promoter by in vitro footprinting with full-length recombinant NFAT protein, and gel shift analysis of nuclear protein from polyclonally activated primary CD4 T cells revealed specific binding of NFAT1 to the NFkappaB binding sites of the HIV-1 LTR. Activation of primary CD4 T cells transiently transfected with a HIV-1 LTR luciferase reporter plasmid, lacking the NFAT binding sites in the upstream putative negative regulatory element but maintaining the NFkappaB/NFAT sites, demonstrated increased HIV-1 gene expression when cotransfected with a NFAT1 expression vector. Moreover, CsA, FK506, and a dominant-negative NFAT1 protein independently inhibited HIV-1 LTR promoter activity in CD4 T cells stimulated with phorbol ester and calcium ionophore. In primary human CD4 T cells, CsA also inhibited promoter activity directed by multimers of binding sites for NFAT, while having no effect on NFkappaB multimer-driven promoter activity. Increasing NFAT1 levels in CD4 T cells transiently transfected with a HIV-1 provirus also increased p24 protein expression. Thus, NFAT may be a target for prevention of HIV-1 LTR-directed gene expression in human CD4 T cells.
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Affiliation(s)
- R Q Cron
- Division of Immunology and Transplantation Biology, Stanford University Medical Center, Palo Alto, California 94304-5208, USA
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50
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Orendi JM, Nottet HS, De Vos NM, Visser MR, Snippe H, Boucher CA, Verhoef J. Hydroxyurea interferes with antigen-dependent T-cell activation in vitro. Eur J Clin Invest 2000; 30:162-6. [PMID: 10651842 DOI: 10.1046/j.1365-2362.2000.00574.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Hydroxyurea is believed to inhibit human immunodeficiency virus type 1 (HIV-1) in HIV disease by decreasing the amount of intracellular deoxynucleotides needed for viral replication. A plasma concentration of 400 micromol L-1 is tolerated in oncological diseases. The present study focused on the possible interference of hydroxyurea with antigen-dependent T-cell activation as an alternative explanation for inhibiting HIV replication in vivo. METHODS The effect of hydroxyurea on common antigen-induced cell proliferation was studied in peripheral blood mononuclear cells (PBMC) in vitro. RESULTS Hydroxyurea inhibited Candida albicans-induced cell proliferation at a low concentration (1 micromol L-1), while at least 10 micromol L-1 was required to block HIV-1 replication in phytohaemagglutinin (PHA)-stimulated PBMC. CONCLUSION Hydroxyurea inhibits antigen-induced lymphoproliferation in vitro at a concentration at which it does not inhibit PHA-induced HIV replication. Hydroxyurea may inhibit HIV-1 in CD4+ T cells in vivo not only by decreasing the amount of intracellular deoxynucleotides, but more specifically by interfering with antigen-dependent T-cell activation, thereby causing a reduction in the number of HIV target cells.
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Affiliation(s)
- J M Orendi
- University Medical Center, Utrecht; Leiden University Medical Center, Leiden, The Netherlands.
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