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Gianella S, Anderson C, Chaillon A, Wells A, Porrachia M, Caballero G, Vargas M, Lonergan J, Woodworth B, Gaitan N, Rawlings SA, Muttera L, Harkness L, Little SJ, May S, Smith D. Impact of influenza and pneumococcal vaccines on HIV persistence and immune dynamics during suppressive antiretroviral therapy. AIDS 2024; 38:1131-1140. [PMID: 38526550 PMCID: PMC11141237 DOI: 10.1097/qad.0000000000003882] [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] [Indexed: 03/26/2024]
Abstract
OBJECTIVE We sought to determine if standard influenza and pneumococcal vaccines can be used to stimulate HIV reservoirs during antiretroviral therapy (ART). DESIGN A prospective, randomized, double-blinded, placebo-controlled, crossover trial of two clinically recommended vaccines (influenza and pneumococcal). METHODS Persons with HIV on ART ( N = 54) were enrolled in the clinical trial. Blood was collected at baseline and days 2,4,7,14, and 30 postimmunizations. Levels of cellular HIV RNA and HIV DNA were measured by ddPCR. Expression of immunological markers on T cell subsets was measured by flow cytometry. Changes in unspliced cellular HIV RNA from baseline to day 7 postinjection between each vaccine and placebo was the primary outcome. RESULTS Forty-seven participants completed at least one cycle and there were no serious adverse events related to the intervention. We observed no significant differences in the change in cellular HIV RNA after either vaccine compared with placebo at any timepoint. In secondary analyses, we observed a transient increase in total HIV DNA levels after influenza vaccine, as well as increased T cell activation and exhaustion on CD4 + T cells after pneumococcal vaccine. CONCLUSION Clinically recommended vaccines were well tolerated but did not appear to stimulate the immune system strongly enough to elicit significantly noticeable HIV RNA transcription during ART.Clinicaltrials.gov identifier: NCT02707692.
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Affiliation(s)
- Sara Gianella
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Christy Anderson
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Antoine Chaillon
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Alan Wells
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Magali Porrachia
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Gemma Caballero
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Milenka Vargas
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Joseph Lonergan
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Brendon Woodworth
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Noah Gaitan
- Department of Medicine, University of California San Diego, La Jolla, CA
| | | | - Leticia Muttera
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Liliana Harkness
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Susan J. Little
- Department of Medicine, University of California San Diego, La Jolla, CA
| | - Susanne May
- Department of Biostatistics, University of Washington, Seattle, WA
| | - Davey Smith
- Department of Medicine, University of California San Diego, La Jolla, CA
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2
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Hentzien M, Bonnet F, Bernasconi E, Biver E, Braun DL, Munting A, Leuzinger K, Leleux O, Musardo S, Prendki V, Schmid P, Staehelin C, Stoeckle M, Walti CS, Wittkop L, Appay V, Didierlaurent AM, Calmy A. Immune response to the recombinant herpes zoster vaccine in people living with HIV over 50 years of age compared to non-HIV age-/gender-matched controls (SHINGR'HIV): a multicenter, international, non-randomized clinical trial study protocol. BMC Infect Dis 2024; 24:329. [PMID: 38504173 PMCID: PMC10949601 DOI: 10.1186/s12879-024-09192-5] [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: 02/14/2024] [Accepted: 03/05/2024] [Indexed: 03/21/2024] Open
Abstract
BACKGROUND The burden of herpes zoster (shingles) virus and associated complications, such as post-herpetic neuralgia, is higher in older adults and has a significant impact on quality of life. The incidence of herpes zoster and post-herpetic neuralgia is increased in people living with HIV (PLWH) compared to an age-matched general population, including PLWH on long-term antiretroviral therapy (ART) with no detectable viremia and normal CD4 counts. PLWH - even on effective ART may- exhibit sustained immune dysfunction, as well as defects in cells involved in the response to vaccines. In the context of herpes zoster, it is therefore important to assess the immune response to varicella zoster virus vaccination in older PLWH and to determine whether it significantly differs to that of HIV-uninfected healthy adults or younger PLWH. We aim at bridging these knowledge gaps by conducting a multicentric, international, non-randomised clinical study (SHINGR'HIV) with prospective data collection after vaccination with an adjuvant recombinant zoster vaccine (RZV) in two distinct populations: in PLWH on long-term ART (> 10 years) over 50 years of and age/gender matched controls. METHODS We will recruit participants from two large established HIV cohorts in Switzerland and in France in addition to age-/gender-matched HIV-uninfected controls. Participants will receive two doses of RZV two months apart. In depth-evaluation of the humoral, cellular, and innate immune responses and safety profile of the RZV will be performed to address the combined effect of aging and potential immune deficiencies due to chronic HIV infection. The primary study outcome will compare the geometric mean titer (GMT) of gE-specific total IgG measured 1 month after the second dose of RZV between different age groups of PLWH and between PLWH and age-/gender-matched HIV-uninfected controls. DISCUSSION The SHINGR'HIV trial will provide robust data on the immunogenicity and safety profile of RZV in older PLWH to support vaccination guidelines in this population. TRIAL REGISTRATION ClinicalTrials.gov NCT05575830. Registered on 12 October 2022. Eu Clinical Trial Register (EUCT number 2023-504482-23-00).
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Affiliation(s)
- Maxime Hentzien
- HIV/AIDS Unit, Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
- University of Reims Champagne-Ardenne, Reims, France
| | - Fabrice Bonnet
- CHU de Bordeaux, Hôpital Saint-André, Service de Médecine Interne et Maladies Infectieuses, Bordeaux, France
- Université de Bordeaux, INSERM, Institut Bergonié, BPH, U1219, CIC-EC 1401, Bordeaux, F-33000, France
| | - Enos Bernasconi
- Department of Infectious Diseases, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Emmanuel Biver
- Division of Bone Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Dominique L Braun
- Division Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Aline Munting
- Service of Infectious Diseases, Centre Hospitalier Universitaire Vaudoise (CHUV), Lausanne, Switzerland
| | | | - Olivier Leleux
- Université de Bordeaux, INSERM, Institut Bergonié, BPH, U1219, CIC-EC 1401, Bordeaux, F-33000, France
| | - Stefano Musardo
- HIV/AIDS Unit, Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Virginie Prendki
- Division of Infectious Disease, Geneva University Hospital, Geneva, Switzerland
| | - Patrick Schmid
- Division of Infectious Diseases and Hospital Epidemiology, Kantonsspital, St Gallen, Switzerland
| | - Cornelia Staehelin
- Department of Infectious Diseases, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Marcel Stoeckle
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Basel, Switzerland
| | - Carla S Walti
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Basel, Switzerland
| | - Linda Wittkop
- CHU de Bordeaux, Hôpital Saint-André, Service de Médecine Interne et Maladies Infectieuses, Bordeaux, France
- CHU de Bordeaux, Service d'information médicale, INSERM, Institut Bergonié, CIC-EC 1401, Bordeaux, F-33000, France
- Inria équipe SISTM team, Talence, France
| | - Victor Appay
- Université de Bordeaux, CNRS UMR 5164, INSERM ERL 1303, ImmunoConcEpT, Bordeaux, 33000, France
| | - Arnaud M Didierlaurent
- Department of Pathology and Immunology, Center of Vaccinology, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
| | - Alexandra Calmy
- HIV/AIDS Unit, Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland.
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3
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Hattenhauer ST, Mispelbaum R, Hentrich M, Boesecke C, Monin MB. Enabling CAR T-cell therapies for HIV-positive lymphoma patients - A call for action. HIV Med 2023; 24:957-964. [PMID: 37322863 DOI: 10.1111/hiv.13514] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 05/09/2023] [Indexed: 06/17/2023]
Abstract
People living with HIV have a higher risk of developing lymphoma. Outcomes for people living with HIV with relapsed or refractory (r/r) lymphoma remain poor. For this group of patients, chimeric antigen receptor (CAR) T-cell therapy represents a new successful treatment strategy. However, people living with HIV were not included in pivotal trials, so data are limited to case reports. We searched the PubMed and Ovid technologies databases for literature until 1 November 2022 using the terms 'HIV and CAR-T', 'HIV and lymphoma' and 'HIV and CAR-T and lymphoma'. Six cases with sufficient information were included in the review. The mean CD4+ T-cell count before CAR T-cell therapy was 221 cells/μL (range 52-629). The viral load was below the limit of detection in four patients. All patients had diffuse large B-cell lymphoma (DLBCL) and were treated with gamma-retroviral-based axicabtagene ciloleucel. Four patients developed cytokine-release syndrome (CRS) grade 2 or less or immune effector-cell-associated neurotoxicity syndrome (ICANs) grade 3-4. Four of six patients responded to CAR T-cell therapy (three complete remissions, one partial remission). In summary, there are no clinical reasons to restrict the use of CAR T-cell therapy in people living with HIV with r/r DLBCL. According to the current data, CAR T-cell therapy was safe and effective. In people who meet the standard criteria for CAR T-cell therapy, this treatment approach could significantly improve the unmet need for more effective treatment options for people living with HIV with r/r lymphoma.
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Affiliation(s)
- Sandra Tessa Hattenhauer
- Department of Oncology, Hematology, Rheumatology and Immune-Oncology, University Hospital Bonn, Bonn, Germany
| | - Rebekka Mispelbaum
- Department of Oncology, Hematology, Rheumatology and Immune-Oncology, University Hospital Bonn, Bonn, Germany
| | - Marcus Hentrich
- Department of Internal Medicine III, Red Cross Hospital Munich, Munich, Germany
| | - Christoph Boesecke
- Department of Internal Medicine I, University Hospital Bonn, Bonn, Germany
- German Centre for Infection Research (DZIF), partner-site Cologne-Bonn, Bonn, Germany
| | - Malte Benedikt Monin
- Department of Internal Medicine I, University Hospital Bonn, Bonn, Germany
- German Centre for Infection Research (DZIF), partner-site Cologne-Bonn, Bonn, Germany
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4
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Bai R, Lv S, Wu H, Dai L. Low-level viremia in treated HIV-1 infected patients: advances and challenges. Curr HIV Res 2022; 20:111-119. [PMID: 35170410 DOI: 10.2174/1570162x20666220216102943] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/30/2021] [Accepted: 01/04/2022] [Indexed: 11/22/2022]
Abstract
Antiretroviral therapy (ART) can effectively suppress HIV-1 replication, improving quality of life and restoring the lifespan of persons living with HIV (PLWH) to near normal levels. However, after standardized ART, a low level of HIV-1 RNA, i.e., low-level viremia (LLV), may still be identified in 3% to 10% of the patients. LLV is capable of impacting the immunological and clinical outcome of patients and serves as a risk factor for transmission. The underlying mechanism of LLV is not yet certain, and the effects of LLV on patient outcomes remain under evaluation. Understanding LLV will allow effective prevention and control strategies to be designed for the benefit of PLWH.
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Affiliation(s)
- Ruojing Bai
- Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Shiyun Lv
- Travel Clinic, Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Hao Wu
- Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Lili Dai
- Travel Clinic, Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China
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5
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Anti-spike antibodies and neutralising antibody activity in people living with HIV vaccinated with COVID-19 mRNA-1273 vaccine: a prospective single-centre cohort study. THE LANCET REGIONAL HEALTH. EUROPE 2021; 13:100287. [PMID: 34961855 PMCID: PMC8694797 DOI: 10.1016/j.lanepe.2021.100287] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Background Vaccines against COVID-19 are a powerful tool to control the current SARS-CoV-2 pandemic. A thorough description of their immunogenicity among people living with HIV (PLWHIV) is necessary. We aimed to assess the immunogenicity of the mRNA-1273 vaccine among PLWHIV. Methods In this prospective cohort, adult PLWHIV outpatients were enrolled during the Italian vaccination campaign. Enrolment was allowed irrespective of ongoing combination antiretroviral therapy (ART), plasma HIV viral load and CD4+ T cell count. A two-dose regimen of mRNA-1273, with administrations performed 28 days apart, was employed. The primary outcomes were anti-spike (anti-S) antibody titres and neutralising antibody activity, assessed 28 days after completing the vaccination schedule. A convenient sample of individuals not affected by HIV was also collected to serve as control (referred as healthy-donors, HDs). Findings We enrolled 71 PLWHIV, mostly male (84·5%), with a mean age of 47 years, a median CD4+ T cell count of 747·0 cells per µL and a median HIV viral load <50 copies/mL. COVID-19-experienced PLWHIV displayed higher anti-S antibody titres (p=0·0007) and neutralising antibody activity in sera (p=0·0007) than COVID-19-naïve PLWHIV. When stratified according to CD4+ T cell count (<350 cells/μL, 350-500 cells/μL, >500 cells/μL), anti-S antibody titres (6/71, median 2173 U/mL [IQR 987-4109]; 7/71, 5763 IU/mL [IQR 4801->12500]; 58/71, 2449 U/mL [IQR 1524-5704]) were not lower to those observed among HDs (10, median 1425 U/mL [IQR 599-6131]). In addition, neutralising antibody activity, stratified according to the CD4+ T cell count (6/71, median 1314 [IQR 606-2477]; 7/71, 3329 IU/mL [IQR 1905-10508]; 58/71, 1227 U/mL [IQR 761-3032]), was like those displayed by HDs (10, median 2112 U/mL [IQR 719-8889]). Interpretation In our cohort of PLWHIV with well-controlled ART, stable viral suppression and robust CD4+ T cell count, inoculation with mRNA-1273 vaccine given 4 weeks apart produced detectable humoral immune response, similar to individuals without HIV infection, supporting vaccination in PLWHIV. Funding This study was partially supported by Italian Ministry of Health Ricerca Corrente 2021, by Intesa San Paolo COVID-19 emergency 2020 funds, and by Fondazione Cariplo Grant (INNATE-CoV).
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6
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Giacomelli A, Micheli V, Cattaneo D, Mancon A, Gervasoni C. Multidrug-resistant HIV viral rebound during early syphilis: a case report. BMC Infect Dis 2020; 20:273. [PMID: 32264923 PMCID: PMC7140389 DOI: 10.1186/s12879-020-04999-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/27/2020] [Indexed: 11/27/2022] Open
Abstract
Background Syphilis has been associated with an increase in HIV RNA and a temporary decline in CD4 T cell counts in people living with HIV who are not receiving antiretroviral treatment (ART), and may be associated with a transient HIV RNA rebound in those who are receiving ART. Our case is the first to highlight the risk of a multidrug-resistant HIV viral rebound during the course of early syphilis even if antiretroviral drug concentrations are within the therapeutic range. Case presentation This 50-year-old HIV-1-positive male patient with concomitant early syphilis presented with an HIV RNA rebound (8908 copies/mL) during a scheduled visit to our clinic. He was receiving a stable ART regimen consisting of darunavir/cobicistat plus dolutegravir, and had a 15-year history of viral suppression. Good short-term drug adherence could be inferred as liquid chromatography tandem mass spectrometry showed that his trough antiretroviral drug concentrations were within the therapeutic range: darunavir 2353 ng/mL (minimum effective concentration > 500 ng/mL) and dolutegravir 986 ng/mL (minimum effective concentration > 100 ng/mL). A plasma RNA genotype resistance test revealed wild-type virus in the integrase region and protease region (PR), but extensive resistance in the reverse transcriptase (RT) region (M41L, E44D, D67N, K70R, M184V, L210W and T215Y). Phylogenetic analysis of next-generation sequences (used to investigate the presence of minor viral variants), the PR and RT sequences from plasma HIV RNA and pro-viral DNA extracted from peripheral blood mononuclear cells during the viral rebound, and a Sanger sequence obtained during a previous virological failure suggested clonal viral expression because the previous PR resistance mutations had been lost or had not been archived in pro-viral DNA. Conclusions This case shows that early syphilis may cause an HIV RNA rebound in patients under stable virological control with the potential of transmitting an extensively drug-resistant virus.
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Affiliation(s)
- Andrea Giacomelli
- Department of Biomedical and Clinical Sciences, DIBIC Luigi Sacco, Milan University, Via G.B. Grassi 74, 20157, Milan, Italy. .,III Infectious Disease Unit, ASST Fatebenefratelli Sacco University Hospital, Milan, Italy.
| | - Valeria Micheli
- Clinical Microbiology, Virology and Bioemergencies, ASST Fatebenefratelli Sacco University Hospital, Milan, Italy
| | - Dario Cattaneo
- Gestione Ambulatoriale Politerapie (GAP) Outpatient Clinic, ASST Fatebenefratelli Sacco University Hospital, Milan, Italy.,Unit of Clinical Pharmacology, ASST Fatebenefratelli Sacco University Hospital, Milan, Italy
| | - Alessandro Mancon
- Clinical Microbiology, Virology and Bioemergencies, ASST Fatebenefratelli Sacco University Hospital, Milan, Italy
| | - Cristina Gervasoni
- III Infectious Disease Unit, ASST Fatebenefratelli Sacco University Hospital, Milan, Italy.,Gestione Ambulatoriale Politerapie (GAP) Outpatient Clinic, ASST Fatebenefratelli Sacco University Hospital, Milan, Italy
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7
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Christensen-Quick A, Chaillon A, Yek C, Zanini F, Jordan P, Ignacio C, Caballero G, Gianella S, Smith D. Influenza Vaccination Can Broadly Activate the HIV Reservoir During Antiretroviral Therapy. J Acquir Immune Defic Syndr 2018; 79:e104-e107. [PMID: 30085954 PMCID: PMC6185804 DOI: 10.1097/qai.0000000000001829] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
| | | | - Christina Yek
- Department of Medicine, University of California, San Diego
| | - Fabio Zanini
- Department of Bioengineering, Stanford University, Stanford, CA
| | - Parris Jordan
- Department of Medicine, University of California, San Diego
| | | | | | - Sara Gianella
- Department of Medicine, University of California, San Diego
| | - Davey Smith
- Department of Medicine, University of California, San Diego
- Veterans Medical Research Foundation, Veterans Affairs Healthcare System, San Diego, CA
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8
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Sörstedt E, Nilsson S, Blaxhult A, Gisslén M, Flamholc L, Sönnerborg A, Yilmaz A. Viral blips during suppressive antiretroviral treatment are associated with high baseline HIV-1 RNA levels. BMC Infect Dis 2016; 16:305. [PMID: 27329293 PMCID: PMC4915053 DOI: 10.1186/s12879-016-1628-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 06/07/2016] [Indexed: 12/01/2022] Open
Abstract
Background Many HIV-1-infected patients on suppressive antiretroviral therapy (ART) have transiently elevated HIV RNA levels. The clinical significance of these viral blips is uncertain. We have determined the incidence of blips and investigated important associations in the Swedish HIV-cohort. Methods HIV-1-infected ART naïve adults who commenced ART 2007–2013 were retrospectively included. Viral blips were defined as a transient viral load between 50 and 500 copies/mL Subjects not suppressed after six months on ART were excluded. Results Viral blips were found in 76/735 included subjects (10.3 %) and in 90/4449 samples (2.0 %). Median blip viral load was 76 copies/mL (range 56–138). Median follow-up time was 170 weeks (range 97–240). Baseline viral load was higher in subjects with viral blips (median log10 4.85 copies/mL) compared with subjects without blips (median log10 4.55 copies/mL) (p < 0.01). There was a significant association between viral blips and risk for subsequent virological failure (p < 0.001). Conclusions The Swedish national HIV-cohort has a low incidence of viral blips (10 %). Blips were associated with high baseline viral load and an increased risk of subsequent virological failure.
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Affiliation(s)
- Erik Sörstedt
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, 413 90, Gothenburg, Sweden.
| | - Staffan Nilsson
- Department of Mathematical Sciences, Chalmers University of Technology, 412 58, Gothenburg, Sweden
| | - Anders Blaxhult
- Department of Infectious Diseases, Venhälsan-Södersjukhuset, 118 83, Stockholm, Sweden
| | - Magnus Gisslén
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, 413 90, Gothenburg, Sweden
| | - Leo Flamholc
- Department of Infectious Diseases, Malmö University Hospital, 205 02, Malmö, Sweden
| | - Anders Sönnerborg
- Department of Infectious Diseases, Karolinska Institute, Karolinska University Hospital, 141 86, Stockholm, Sweden.,Department of Clinical Microbiology, Karolinska Institute, Karolinska University Hospital, 141 86, Stockholm, Sweden
| | - Aylin Yilmaz
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, 413 90, Gothenburg, Sweden
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Briggs R, Templeton K, Fernando I. Comparing HIV viral load assays and frequency of low level virological rebound in clinical practice. Int J STD AIDS 2014; 25:1029-34. [DOI: 10.1177/0956462414528313] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Research suggests that some low-level virological rebound results occurring for no obvious clinical cause, in patients stable on antiretroviral therapy (ART), may be a consequence of the viral load assay used. We compared the relative frequency of clinically unexplained low-level virological rebound results when using the Roche HIV Taqman version-1 (CTM v1), the Roche HIV Taqman version-2 (CTM v2) and the Abbott RealTime (Abbott RT) assays in clinical practice. In all, 247 patients from our centre who had their viral loads measured by the three different assays over a period of 3 consecutive years (each assay used for a period of 1 year each) were included in the study. Low-level virological rebound was defined as <1000 copies/ml. Over similar time periods, there was significant discrepancy between the three assays when considering the proportion of clinically unexplained low-level virological rebound results in patients stable on ART: the CTM v2 assay produced the highest percentage (93%), CTM v1 much lower (65%) and Abbott RT even less (35%). There is further research required regarding what, if any, implications this has for patients who experience clinically unexplained low-level virological rebound on the more sensitive assays.
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Affiliation(s)
- R Briggs
- University of Edinburgh Medical School, Edinburgh, UK
| | - K Templeton
- Microbiology and Virology Laboratories, Royal Infirmary of Edinburgh, NHS Lothian, Edinburgh, UK
| | - I Fernando
- Chalmers Sexual Health Centre, NHS Lothian, Edinburgh, UK
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10
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Diaz RS, Tenore SB, da Silva MMG, da Cunha CA. A Phase III, randomized study to evaluate the immunogenicity and safety of an MF59®-adjuvanted A/H1N1 pandemic influenza vaccine in HIV-positive adults. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.trivac.2014.07.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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11
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Comparison of HIV-1 viral load assay performance in immunological stable patients with low or undetectable viremia. Med Microbiol Immunol 2012; 202:67-75. [PMID: 22699843 DOI: 10.1007/s00430-012-0249-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 05/26/2012] [Indexed: 10/27/2022]
Abstract
The goal of antiretroviral therapy is reduction in morbidity and mortality via suppression of human immunodeficiency virus (HIV) viral load (VL) to undetectable levels. VL assay sensitivity has improved over time, but the reproducibility and clinical importance of VL results marginally higher than the limit of detection (LoD) are uncertain. We assessed the reproducibility and concordance of low VL results obtained with the Roche Cobas AmpliPrep/Cobas TaqMan HIV-1 version 2.0 (CAP-CTM) and the Abbott RealTime (m2000) HIV-1 assays, using longitudinal specimens from HIV-1-infected patients with low VL (<300 copies/ml) and stable CD4+ cell counts. Based on replicate testing of 3 specimens, coefficients of variation for log-transformed VL results were 5-8 % for m2000 and 9-10 % for CAP-CTM. The concordance between assays in specimens from patients with previously undetectable, detectable but not quantifiable VL, or variable (undetectable/detectable but not quantifiable VL) results over time was 90, 56, and 56 %, respectively. Correlation between results for specimens with quantifiable VL (initially 40-300 copies/ml) was moderate (R (2) = 0.48) with significantly higher results for CAP-CTM and a mean difference (CAP-CTM minus m2000) of 0.10 log(10) copies/ml. T-cell activation (CD8+/CD38+ percentage) in patients with low VL was initially higher than in patients with undetectable VL, and then decreased to equivalent levels over time. These results indicate that residual viremia at levels slightly above the LoD have no negative effect on T-cell activation.
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12
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Antón A, Pumarola T. Influenza in immunocompromised patients: considerations for therapy. Future Virol 2011. [DOI: 10.2217/fvl.11.61] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Influenza infection results in substantial morbidity and mortality in immunocompromised patients, and the risks for influenza and its related complications depend on the degree of immunosuppression. In addition to influenza vaccination and infection control precautions, two classes of antiviral drugs are currently approved for treatment and prophylaxis in uncomplicated infected patients. However, there are no randomized controlled trials assessing the efficacy and safety of licensed antivirals for influenza management in immunocompromised patients. The purpose of this article is to highlight some considerations for therapy in immunocompromised patients, the usefulness of vaccination for the prevention of influenza and the clinical interest in surveillance of antiviral resistance.
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Affiliation(s)
| | - Tomás Pumarola
- Virology Section, Department of Microbiology, Barcelona Centre for International Health Research (CRESIB, Hospital Clínic – Universitat de Barcelona), 08036 Barcelona, Spain
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Abstract
OBJECTIVE To evaluate the safety and immunogenicity of the H1N1 2009 vaccine in HIV-positive individuals. DESIGN A single-arm study. SETTING Clinic at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA. PARTICIPANTS HIV-infected adults with an indication for H1N1 vaccination. INTERVENTION Single intramuscular 15 microg dose of the monovalent, unadjuvanted, inactivated, split virus H1N1 vaccine. MAIN OUTCOMES Immunogenicity, safety and tolerability. RESULTS A total of 120 participants were enrolled, 71% men, 68% African-American, with median age of 46 years. All of them but one were on antiretroviral treatment, with a median current CD4 cell counts of 502 cells/microl, and a nadir CD4 cell counts of 132 cells/microl. The HIV RNA level was below 400 copies/ml in 92% of participants. All participants completed the 3 weeks of follow-up. Thirty of the 120 (25%) participants had antibody hemagglutination-inhibition assay titers equal or greater than 1: 40 at baseline. Among participants without evidence of previous exposure, only 61% develop protective titers by week 3 of the study. Nonresponders had lower current and nadir CD4 cell counts than responders. Only four of nine participants with detectable HIV viral load at baseline developed protective antibody titers. Age and race were not predictors of the response to the vaccine. The vaccine was well tolerated. CONCLUSION These results suggest that only 60% of well controlled HIV-infected individuals without preexisting immunity to H1N1 develop protective antibody titers after immunization. Alternative vaccines, dosing, adjuvants or schedule strategies are needed to achieve effective immunization of this vulnerable population.
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Castro P, Plana M, González R, López A, Vilella A, Argelich R, Gallart T, Pumarola T, Bayas JM, Gatell JM, García F. Influence of a vaccination schedule on viral load rebound and immune responses in successfully treated HIV-infected patients. AIDS Res Hum Retroviruses 2009; 25:1249-59. [PMID: 19943787 DOI: 10.1089/aid.2009.0015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Vaccination is recommended for HIV-infected patients. Transient increases of viral load (VL) and risk of developing resistance to HAART have been described. In addition, VL rebounds could increase HIV-specific immune responses. Twenty-six successfully treated HIV-infected adults were randomized to receive a vaccination schedule or placebo during 12 months. Afterward, HAART was discontinued. Influences of vaccination over VL, genotypic mutations, different T cell subsets, and HIV-1-specific immune responses were evaluated. Patients did not present any secondary effect. No differences in incidence of detectable VL determinations were detected between groups [relative risk 0.54 (95% CI 0.23-1.26)]. No relevant resistance mutations were detected. The vaccinated group showed a significant drop in CD4(+) T cells (p = 0.046) associated with increases in activated T cells. HIV-1-specific lymphoproliferative responses increased more in the vaccinated group during the vaccination period. Viral rebound dynamics after interrupting HAART were similar in both groups. A vaccination schedule in successfully treated HIV patients was safe, was not associated with an increase in detectable VL, and did not increase the risk of developing resistance mutations. However, it induced an increase in T cell activation and a drop in CD4(+) T cells, although these changes did not influence the VL rebound dynamics after HAART interruption.
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Affiliation(s)
- Pedro Castro
- Medical Intensive Care Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - Montserrat Plana
- Retrovirology and Viral Immunopathology Laboratories, IRSICAIXA-HIVACAT, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - Raquel González
- Preventive Medicine Department Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - Anna López
- Retrovirology and Viral Immunopathology Laboratories, IRSICAIXA-HIVACAT, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - Anna Vilella
- Preventive Medicine Department Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - Roger Argelich
- Infectious Diseases Unit, HIV Vaccine Development in Catalonia (HIVACAT), Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - Teresa Gallart
- Retrovirology and Viral Immunopathology Laboratories, IRSICAIXA-HIVACAT, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
- Immunology Laboratory, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - Tomàs Pumarola
- Microbiology Laboratory, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - José M. Bayas
- Preventive Medicine Department Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - José M. Gatell
- Infectious Diseases Unit, HIV Vaccine Development in Catalonia (HIVACAT), Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - Felipe García
- Infectious Diseases Unit, HIV Vaccine Development in Catalonia (HIVACAT), Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
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15
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Kunisaki KM, Janoff EN. Influenza in immunosuppressed populations: a review of infection frequency, morbidity, mortality, and vaccine responses. THE LANCET. INFECTIOUS DISEASES 2009; 9:493-504. [PMID: 19628174 DOI: 10.1016/s1473-3099(09)70175-6] [Citation(s) in RCA: 390] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Patients that are immunosuppressed might be at risk of serious influenza-associated complications. As a result, multiple guidelines recommend influenza vaccination for patients infected with HIV, who have received solid-organ transplants, who have received haemopoietic stem-cell transplants, and patients on haemodialysis. However, immunosuppression might also limit vaccine responses. To better inform policy, we reviewed the published work relevant to incidence, outcomes, and prevention of influenza infection in these patients, and in patients being treated chemotherapy and with systemic corticosteroids. Available data suggest that most immunosuppressed populations are indeed at higher risk of influenza-associated complications, have a general trend toward impaired humoral vaccine responses (although these data are mixed), and can be safely vaccinated--although longitudinal data are largely lacking. Randomised clinical trial data were limited to one study of HIV-infected patients with high vaccine efficacy. Better trial data would inform vaccination recommendations on the basis of efficacy and cost in these at-risk populations.
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Affiliation(s)
- Ken M Kunisaki
- Pulmonary Section, Minneapolis Veterans Affairs Medical Center, Minneapolis, MN 55417, USA.
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16
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Geretti AM, Brook G, Cameron C, Chadwick D, Heyderman RS, MacMahon E, Pozniak A, Ramsay M, Schuhwerk M. British HIV Association guidelines for immunization of HIV-infected adults 2008. HIV Med 2009; 9:795-848. [PMID: 18983477 DOI: 10.1111/j.1468-1293.2008.00637.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- A M Geretti
- Department of Virology, Royal Free Hospital, Royal Free and University College Medical School, Pond Street, London NW3 2QG, UK.
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17
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[Effects of influenza vaccination on the percentage of CD4+ T lymphocytes in HIV 1/2 positive patients: a cohort study]. GACETA SANITARIA 2009; 23:315-21. [PMID: 19286280 DOI: 10.1016/j.gaceta.2008.10.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 07/24/2008] [Accepted: 11/03/2008] [Indexed: 11/21/2022]
Abstract
OBJECTIVE To determine the incidence of immunologic change in the percentage of CD4+ T lymphocytes in HIV 1/2 positive patients in the first quarter after influenza vaccination (P-CIR) and to compare the demographic and clinical characteristics associated with this change. METHODS We studied 105 patients with HIV/AIDS in a retrospective hospital cohort between 2001-2006. P-CIR was considered as a decrease of >3% in the prevaccination CD4+ percentage. Crude and adjusted OR (sex, age, antiretroviral therapy, clinical stability, prevaccination viremia and prevaccination total CD4) were evaluated by logistic regression (95%CI). RESULTS The incidence of P-CIR was 33.3%. P-CIR was persistent in 31.4% for 7 months after vaccination regardless of high prevaccination viremia. No association was found between demographic and clinical variables and P-CIR [crude OR: 0.90 (0.17-4.8); adjusted OR: 1.09 (0.17-6.8)]. CONCLUSIONS The results showed that the immunological change after vaccination was not inconsiderable. However, this change was mainly transient.
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19
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Jones LE, Perelson AS. Transient viremia, plasma viral load, and reservoir replenishment in HIV-infected patients on antiretroviral therapy. J Acquir Immune Defic Syndr 2007; 45:483-93. [PMID: 17496565 PMCID: PMC2584971 DOI: 10.1097/qai.0b013e3180654836] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
When antiretroviral therapy (ART) is administered for long periods to HIV-1-infected patients, most achieve viral loads that are "undetectable" by standard assay methods (ie, HIV-1 RNA <50 copies/mL). Despite sustaining viral loads lower than the level of detection, a number of patients experience unexplained episodes of transient viremia or viral "blips." We propose that transient activation of the immune system by infectious agents may explain these episodes of viremia. Using 2 different mathematical models, one in which blips arise because of target cell activation and subsequent infection and another in which latent cell activation generates blips, we establish a nonlinear (power law) relationship between blip amplitude and viral load (under ART) that suggest blips should be of lower amplitude, and thus harder to detect, as increasingly potent therapy is used. This effect can be more profound than is predicted by simply lowering the baseline viral load from which blips originate. Finally, we suggest that sporadic immune activation may elevate the level of chronically infected cells and replenish viral reservoirs, including the latent cell reservoir, providing a mechanism for recurrent viral blips and low levels of viremia under ART.
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Affiliation(s)
- Laura E. Jones
- Ecology and Evolutionary Biology, Cornell University, Ithaca, NY
| | - Alan S. Perelson
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM
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20
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Tanzi E, Esposito S, Bojanin J, Amendola A, Trabattoni D, Pariani E, Pinzani R, Zanetti A, Principi N. Immunogenicity and effect of a virosomal influenza vaccine on viral replication and T-cell activation in HIV-infected children receiving highly active antiretroviral therapy. J Med Virol 2006; 78:440-5. [PMID: 16482542 DOI: 10.1002/jmv.20559] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In order to evaluate the immunogenicity and the effect of a virosomal influenza vaccine on viral replication and T-cell activation in HIV-infected children receiving highly active antiretroviral therapy (HAART), 29 children infected with HIV-1 vertically (19 primed with a previous influenza vaccination and 10 who were not been immunized against influenza) were immunized with an intramuscular virosome-adjuvanted influenza vaccine. According to the European Agency for Evaluation of Medical Products (EMEA) criteria, the immunogenicity of the vaccine was adequate against all three influenza strains (A H1N1, A H3N2, and B) in the primed children, and against A H1N1 and A H3N2 in the unprimed children. After in vitro stimulation with vaccine antigens, the IFN-gamma levels in the peripheral blood mononuclear cells cultures increased significantly from a baseline level of 103.0 +/- 229.8 pg/ml to a 30-day level of 390.7 +/- 606.3 pg/ml (P < 0.05), with concentrations significantly higher (P < 0.05) in the primed children than in the unprimed children. No increase in plasma HIV-1 RNA or HIV-1 proviral DNA was observed in either subgroup, and the immunophenotype analyses demonstrated that the CD4+ cell counts and percentages, the CD4/CD8 ratio and activated lymphocytes remained stable in either group from baseline to 1 month after each vaccine dose. This study showed that the virosomal influenza vaccine does seem to be immunogenic in the majority of HIV-infected children receiving HAART and does not induce viral replication or T-cell activation. Given the possible influenza-related complications in children infected with HIV, these results support the use of this influenza vaccine in such patients.
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Affiliation(s)
- Elisabetta Tanzi
- Department of Public Health-Microbiology-Virology, University of Milan, Milan, Italy
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21
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Sallie R. Replicative homeostasis: a fundamental mechanism mediating selective viral replication and escape mutation. Virol J 2005; 2:10. [PMID: 15707489 PMCID: PMC552327 DOI: 10.1186/1743-422x-2-10] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2005] [Accepted: 02/11/2005] [Indexed: 01/12/2023] Open
Abstract
Hepatitis C (HCV), hepatitis B (HBV), the human immunodeficiency viruses (HIV), and other viruses that replicate via RNA intermediaries, cause an enormous burden of disease and premature death worldwide. These viruses circulate within infected hosts as vast populations of closely related, but genetically diverse, molecules known as "quasispecies". The mechanism(s) by which this extreme genetic and antigenic diversity is stably maintained are unclear, but are fundamental to understanding viral persistence and pathobiology. The persistence of HCV, an RNA virus, is especially problematic and HCV stability, maintained despite rapid genomic mutation, is highly paradoxical. This paper presents the hypothesis, and evidence, that viruses capable of persistent infection autoregulate replication and the likely mechanism mediating autoregulation - Replicative Homeostasis - is described. Replicative homeostasis causes formation of stable, but highly reactive, equilibria that drive quasispecies expansion and generates escape mutation. Replicative homeostasis explains both viral kinetics and the enigma of RNA quasispecies stability and provides a rational, mechanistic basis for all observed viral behaviours and host responses. More importantly, this paradigm has specific therapeutic implication and defines, precisely, new approaches to antiviral therapy. Replicative homeostasis may also modulate cellular gene expression.
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22
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Sallie R. Replicative homeostasis: a mechanism of viral persistence. Med Hypotheses 2005; 63:515-23. [PMID: 15288380 DOI: 10.1016/j.mehy.2004.02.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2004] [Accepted: 02/21/2004] [Indexed: 01/12/2023]
Abstract
Acute viral infection is characterised by high-level replication before prompt decline of viraemia and, commonly, viral clearance. This kinetic pattern is generally held to be due to immune control. However, infection with some viruses, notably hepatitis C (HCV), hepatitis B (HBV) and the human immunodeficiency virus (HIV), often results in chronic stable low-level spontaneously fluctuating viraemia, kinetics that are difficult to rationalize on this basis. The persistence of HCV, an RNA virus, is especially problematic and its stability, occurring despite rapid, genomic mutation is highly paradoxical. This paper outlines the hypothesis, and evidence, that viruses autoregulate replication and mutation and describes a mechanism--replicative homeostasis--explaining viral stability. Replicative homeostasis results in stable, but reactive, replicative equilibria that drive quasispecies expansion and immune escape and explain all observed viral behaviours and host responses. This paradigm implies new approaches to antiviral therapy and is broadly relevant to modulation of gene expression.
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Affiliation(s)
- Richard Sallie
- St John of God Hospital, Western Gastroenterology, Suite 35, 95 Monash Avenue, Nedlands, Perth, WA 6009, Australia.
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23
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Maggi F, Tempestini E, Lanini L, Andreoli E, Fornai C, Giannecchini S, Vatteroni M, Pistello M, Marchi S, Ciccorossi P, Specter S, Bendinelli M. Blood levels of TT virus following immune stimulation with influenza or hepatitis B vaccine. J Med Virol 2005; 75:358-65. [PMID: 15602718 DOI: 10.1002/jmv.20278] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Torque Teno virus (TTV) has been demonstrated to be present persistently in the blood of healthy individuals without evidence that it causes any disease process. The levels of TTV vary in patients co-infected with other viruses and there has been considerable speculation as to whether TTV contributes to pathogenesis by other viruses or if the varying levels might be related to immune activation in the host. In the present study, the load of TTV was examined in plasma and peripheral blood mononuclear cells (PBMCs) following immunization of subjects with either influenza (a recall antigen) or hepatitis B virus (HBV) (a new antigenic exposure). The results overall did not indicate a significant change in TTV titers over a 90 day observation period; however, when TTV genogroup was taken into consideration there was an increase in viral load in plasma at some time points for subjects persistently infected with genogroup 3. While this was observed in both influenza and HBV immunized subjects, the effect was more profound in HBV vaccination. Thus, it appears that exposure to a new antigen rather than a recall antigen may stimulate TTV replication more effectively. The data further suggest that investigating the interactions between TTV and its host might require to examine specifically each TTV genogroup separately in order to determine if certain TTV types have any role in disease pathogenesis.
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Affiliation(s)
- Fabrizio Maggi
- Virology Section and Retrovirus Center, Department of Experimental Pathology, University of Pisa, Pisa, Italy
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Abstract
Influenza remains an important epidemic viral infection. Thousands of deaths occur and billions of dollars are spent each year with influenza-related illnesses. Morbidity and mortality are largely attributed to respiratory complications that may require intensive care unit (ICU) admission. Medical and neonatal ICUs, transplant units, chronic-care wards, and nursing homes are at increased risk for nosocomial outbreaks of influenza, which are characterized by abrupt onset and rapid spread. In this article, the authors review the current concepts, recent advances, and management strategies in influenza-associated pneumonia. Pertinent issues to the critical care practitioner are discussed in detail.
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Affiliation(s)
- Eduardo C Oliveira
- Division of Pulmonary and Critical Care Medicine, Cleveland Clinic Florida, 2950 Cleveland Clinic Boulevard, Weston, FL, USA.
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25
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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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26
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Abstract
There is a wealth of data supporting the use of viral load measurements to monitor therapy. Indeed, clinical drug trial endpoints routinely include the proportion of patients with a plasma viral load reduction of greater than 0.5 log(10), or greater than 1 log(10). Since a higher viral load reflects increased amounts of virus replication, it would seem desirable to reduce this replication as far as possible, so that the goal of therapy has become one of viral undetectability in plasma. However, virological suppression to undetectable levels is not an absolute determinant of outcome because recent observational cohort data suggest that any significant reduction of viral load is associated with clinical benefit. There are also technical problems when attempting to measure undetectability, with lower limits of detection of 400 or 50 RNA copies/ml of plasma being driven more by the performance of commercial assays than by any inherent cut-off value with proven prognostic significance. Furthermore, the obsession with undetectability has created the concept of the 'viral blip', or 'intermittent viraemia' commonly defined as a single viral load measurement of between 50 and 400 copies/ml, preceded and followed by consistent measurements of less than 50 copies/ml, in a patient receiving therapy. Such blips should be considered in the context of frequent transient changes in viral load which occur below the lower limit of detection by existing laboratory assays. In my view, there remains a misunderstanding about the importance ascribed to these relatively minor changes in lower detection limits, when considered against the background of virus within the body as a whole. I also consider other possible uses of HIV-1 quantification in clinical practice, such as identifying the inherent potency of antiviral regimens.
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Affiliation(s)
- Deenan Pillay
- PHLS Antiviral Susceptibility Reference Unit, Public Health Laboratory, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK.
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