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Find video protocols related to scientific articles indexed in Pubmed.
Phase I/II Randomized Trial of Safety and Immunogenicity of LIPO-5 Alone, ALVAC-HIV (vCP1452) Alone, and ALVAC-HIV (vCP1452) Prime/LIPO-5 Boost in Healthy, HIV-1-Uninfected Adult Participants.
Clin. Vaccine Immunol.
PUBLISHED: 09-24-2014
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Finding an effective human immunodeficiency virus type 1 (HIV-1) vaccine remains a major global health priority. In a phase I/II, placebo-controlled trial, healthy, HIV-1-negative adults were randomized to receive one of 5 vaccine regimens: LIPO-5 (combination of 5 lipopeptides) alone (250 ?g), ALVAC-HIV (vCP1452) alone, or 3 groups of ALVAC-HIV (vCP1452) followed by ALVAC-HIV (vCP1452) plus LIPO-5 (250, 750, and 2,500 ?g). Only 73/174 participants (42%) received all four vaccinations due to a study halt related to myelitis. There were no significant differences in systemic reactions between groups or in local reactogenicity between groups receiving ALVAC-HIV (vCP1452). Significant differences in local reactogenicity occurred between groups receiving LIPO-5 (P ? 0.05). Gag and Env antibodies were undetectable by ELISA 2 weeks after the fourth vaccination for all but one recipient. Antibodies to Gag and Env were present in 32% and 24% of recipients of ALVAC-HIV (vCP1452) alone and in 47% and 35% of ALVAC-HIV (vCP1452)+LIPO recipients, respectively. Coadministration of LIPO-5 did not significantly increase the response rate compared to ALVAC-HIV (vCP1452) alone, nor was there a significant relationship between dose and antibody responses among ALVAC-HIV (vCP1452)+LIPO groups. Over 90% of study participants had no positive gamma interferon (IFN-?) enzyme-linked immunosorbent spot assay (ELISpot) responses to any peptide pool at any time point. The study was halted due to a case of myelitis possibly related to the LIPO-5 vaccine; this case of myelitis remains an isolated event. In general, there was no appreciable cell-mediated immunity detected in response to the vaccines used in this study, and antibody responses were limited. The clinical trial is registered on ClinicalTrials.gov with registry number NCT00076063.
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Reduced human herpesvirus-8 oropharyngeal shedding associated with protease inhibitor-based antiretroviral therapy.
J. Clin. Virol.
PUBLISHED: 02-21-2014
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Human herpesvirus 8 (HHV-8) replication increases the risk of Kaposi sarcoma (KS). Highly-active antiretroviral therapy (HAART) reduces the incidence of KS, and regimens that contain protease inhibitors (PIs) may be particularly effective.
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Recombinant adenovirus type 5 HIV gag/pol/nef vaccine in South Africa: unblinded, long-term follow-up of the phase 2b HVTN 503/Phambili study.
Lancet Infect Dis
PUBLISHED: 02-20-2014
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The HVTN 503/Phambili study, which assessed the efficacy of the Merck Ad5 gag/pol/nef subtype B HIV-1 preventive vaccine in South Africa, was stopped when futility criteria in the Step study (assessing the same vaccine in the Americas, Caribbean, and Australia) were met. Here we report long-term follow-up data.
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Virologic and immunologic evidence of multifocal genital herpes simplex virus 2 infection.
J. Virol.
PUBLISHED: 02-19-2014
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Genital herpes simplex virus (HSV) reactivation is thought to be anatomically and temporally localized, coincident with limited ganglionic infection. Short, subclinical shedding episodes are the most common form of HSV-2 reactivation, with host clearance mechanisms leading to rapid containment. The anatomic distribution of shedding episodes has not been characterized. To precisely define patterns of anatomic reactivation, we divided the genital tract into a 22-region grid and obtained daily swabs for 20 days from each region in 28 immunocompetent, HSV-2-seropositive persons. HSV was detected via PCR, and sites of asymptomatic HSV shedding were subjected to a biopsy procedure within 24 h. CD4(+) and CD8(+) T cells were quantified by immunofluorescence, and HSV-specific CD4(+) T cells were identified by intracellular cytokine cytometry. HSV was detected in 868 (7%) of 11,603 genital swabs at a median of 12 sites per person (range, 0 to 22). Bilateral HSV detection occurred on 83 (67%) days with shedding, and the median quantity of virus detected/day was associated with the number of sites positive (P < 0.001). In biopsy specimens of asymptomatic shedding sites, we found increased numbers of CD8(+) T cells compared to control tissue (27 versus 13 cells/mm(2), P = 0.03) and identified HSV-specific CD4(+) T cells. HSV reactivations emanate from widely separated anatomic regions of the genital tract and are associated with a localized cellular infiltrate that was demonstrated to be HSV specific in 3 cases. These data provide evidence that asymptomatic HSV-2 shedding contributes to chronic inflammation throughout the genital tract.
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Frequent genital HSV-2 shedding among women during labor in Soweto, South Africa.
Infect Dis Obstet Gynecol
PUBLISHED: 01-21-2014
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Despite high herpes simplex virus type 2 (HSV-2) incidence and prevalence among women in Africa, we are unaware of published neonatal herpes reports. To assess neonatal HSV transmission potential in South Africa, we investigated the frequency of the strongest risk factors: HSV acquisition in late pregnancy and HSV shedding during labor.
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Helicase-primase inhibitor pritelivir for HSV-2 infection.
N. Engl. J. Med.
PUBLISHED: 01-17-2014
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Pritelivir, an inhibitor of the viral helicase-primase complex, exhibits antiviral activity in vitro and in animal models of herpes simplex virus (HSV) infection. We tested the efficacy and safety of pritelivir in otherwise healthy persons with genital HSV-2 infection.
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Nuclear factor kappa B is required for the production of infectious human herpesvirus 8 virions.
Front Microbiol
PUBLISHED: 01-01-2014
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Human herpesvirus 8 (HHV8) infection leads to potent activation of nuclear factor kappa B (NF?B) in primary and transformed cells. We used recombinant HHV8 (rKSHV.219) expressing green fluorescent protein under the constitutive cellular promoter elongation factor 2? and red fluorescent protein under an early HHV8 lytic gene promoter T1.1 to monitor replication during infection of human foreskin fibroblasts (HF), noting changes in NF?B activity. In primary HF, NF?B levels do not affect the ability of HHV8 to establish infection or maintain latency. Furthermore, there was no effect on the percent of cells undergoing reactivation from latency, and there were similar numbers of released and cell-associated HHV8 viral particles following reactivation in the presence of inhibitors. Reactivation of HHV8 in latently infected HF in the presence of NF?B inhibitors resulted in production of viral particles that did not efficiently establish infection, due to deficiencies in binding and/or entry into normally permissive cells. Exogenous expression of glycoprotein M, an envelope protein involved in viral binding and entry, was able to partially overcome the deficiency induced by NF?B inhibitors. Our data indicate that in primary cells, NF?B is not required for infection, establishment of latency, or entry into the lytic cycle, but is required for the expression of virion associated genes involved in the initial steps of virion infectivity. These studies suggest that strategies to inhibit NF?B may prevent HHV8 spread and should be considered as a potential therapeutic target for preventing HHV8 associated diseases.
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Efficacy trial of a DNA/rAd5 HIV-1 preventive vaccine.
N. Engl. J. Med.
PUBLISHED: 10-07-2013
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A safe and effective vaccine for the prevention of human immunodeficiency virus type 1 (HIV-1) infection is a global priority. We tested the efficacy of a DNA prime-recombinant adenovirus type 5 boost (DNA/rAd5) vaccine regimen in persons at increased risk for HIV-1 infection in the United States.
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Rapid viral expansion and short drug half-life explain the incomplete effectiveness of current herpes simplex virus 2-directed antiviral agents.
Antimicrob. Agents Chemother.
PUBLISHED: 09-09-2013
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The nucleoside analogues acyclovir (ACV) and famciclovir (FCV) reduce the frequency and severity of herpes simplex virus 2 (HSV-2) genital shedding, yet despite their high potency in vitro and a lack of induced drug resistance, frequent episodes of breakthrough mucosal shedding occur. We tested a published stochastic, spatial mathematical model of HSV-2 replication and spread, in concert with pharmacokinetic and pharmacodynamic equations, against virologic data from clinical trials of twice-daily acyclovir and famciclovir suppression. The model reproduced the key features of clinical trial data, including genital shedding episode rate, expansion and decay dynamics, and heterogeneous peak viral production and duration. In simulations, these agents shortened episode duration by limiting the extent of viral production by 1 to 2 log units and limiting the formation of secondary ulcers by ?50%. However, drug concentrations were noninhibitory during 42% of the dosing cycle. Even if drug concentrations were high at episode initiation, prolonged episodes often ensued due to drug decay over ensuing hours and subsequent rebound of rapidly replicating HSV-2. The local CD8(+) T-cell density was more predictive of episode viral production (R(2) = 0.42) and duration (R(2) = 0.21) than the drug concentration at episode onset (R(2) = 0.14 and 0.05, respectively), though the model projected that an agent with an equivalent potency but a two times longer half-life would decrease shedding by 80% compared to that of standard twice-daily regimens. Therefore, long half-life is a key characteristic of any agent that might fully suppress HSV-2 reactivations.
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Daily acyclovir to decrease herpes simplex virus type 2 (HSV-2) transmission from HSV-2/HIV-1 coinfected persons: a randomized controlled trial.
J. Infect. Dis.
PUBLISHED: 07-30-2013
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Daily suppressive therapy with valacyclovir reduces risk of sexual transmission of herpes simplex virus type 2 (HSV-2) in HSV-2-serodiscordant heterosexual couples by 48%. Whether suppressive therapy reduces HSV-2 transmission from persons coinfected with HSV-2 and human immunodeficiency virus type 1 (HIV-1) is unknown.
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HLA targeting efficiency correlates with human T-cell response magnitude and with mortality from influenza A infection.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-22-2013
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Experimental and computational evidence suggests that HLAs preferentially bind conserved regions of viral proteins, a concept we term "targeting efficiency," and that this preference may provide improved clearance of infection in several viral systems. To test this hypothesis, T-cell responses to A/H1N1 (2009) were measured from peripheral blood mononuclear cells obtained from a household cohort study performed during the 2009-2010 influenza season. We found that HLA targeting efficiency scores significantly correlated with IFN-? enzyme-linked immunosorbent spot responses (P = 0.042, multiple regression). A further population-based analysis found that the carriage frequencies of the alleles with the lowest targeting efficiencies, A*24, were associated with pH1N1 mortality (r = 0.37, P = 0.031) and are common in certain indigenous populations in which increased pH1N1 morbidity has been reported. HLA efficiency scores and HLA use are associated with CD8 T-cell magnitude in humans after influenza infection. The computational tools used in this study may be useful predictors of potential morbidity and identify immunologic differences of new variant influenza strains more accurately than evolutionary sequence comparisons. Population-based studies of the relative frequency of these alleles in severe vs. mild influenza cases might advance clinical practices for severe H1N1 infections among genetically susceptible populations.
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HIV-1 vaccine-induced T-cell responses cluster in epitope hotspots that differ from those induced in natural infection with HIV-1.
PLoS Pathog.
PUBLISHED: 06-01-2013
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Several recent large clinical trials evaluated HIV vaccine candidates that were based on recombinant adenovirus serotype 5 (rAd-5) vectors expressing HIV-derived antigens. These vaccines primarily elicited T-cell responses, which are known to be critical for controlling HIV infection. In the current study, we present a meta-analysis of epitope mapping data from 177 participants in three clinical trials that tested two different HIV vaccines: MRKAd-5 HIV and VRC-HIVAD014-00VP. We characterized the population-level epitope responses in these trials by generating population-based epitope maps, and also designed such maps using a large cohort of 372 naturally infected individuals. We used these maps to address several questions: (1) Are vaccine-induced responses randomly distributed across vaccine inserts, or do they cluster into immunodominant epitope hotspots? (2) Are the immunodominance patterns observed for these two vaccines in three vaccine trials different from one another? (3) Do vaccine-induced hotspots overlap with epitope hotspots induced by chronic natural infection with HIV-1? (4) Do immunodominant hotspots target evolutionarily conserved regions of the HIV genome? (5) Can epitope prediction methods be used to identify these hotspots? We found that vaccine responses clustered into epitope hotspots in all three vaccine trials and some of these hotspots were not observed in chronic natural infection. We also found significant differences between the immunodominance patterns generated in each trial, even comparing two trials that tested the same vaccine in different populations. Some of the vaccine-induced immunodominant hotspots were located in highly variable regions of the HIV genome, and this was more evident for the MRKAd-5 HIV vaccine. Finally, we found that epitope prediction methods can partially predict the location of vaccine-induced epitope hotspots. Our findings have implications for vaccine design and suggest a framework by which different vaccine candidates can be compared in early phases of evaluation.
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The need and challenges for development of an Epstein-Barr virus vaccine.
Vaccine
PUBLISHED: 04-20-2013
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Epstein-Barr virus (EBV) is the major cause of infectious mononucleosis and is associated with several malignancies including nasopharyngeal carcinoma, gastric carcinoma, Hodgkin lymphoma, Burkitt lymphoma, and lymphoma after organ or stem cell transplant. A candidate vaccine containing soluble EBV glycoprotein gp350 protected cottontop tamarins from EBV lymphoma after challenge with EBV. In the only phase 2 trial of an EBV vaccine in humans, soluble gp350 in alum and monophosphoryl lipid A adjuvant reduced the rate of infectious mononucleosis in EBV seronegative adults, but did not affect the rate of EBV infection. A peptide vaccine corresponding to EBV latency proteins has been tested in a small number of adults to prevent infectious mononucleosis. Some of the barriers to development of an EBV vaccine include (a) whether viral proteins in addition to gp350 would be more effective for preventing mononucleosis or EBV malignancies, (b) the difficulty of performing clinical trials to prevent EBV associated malignancies in the absence of good surrogate markers for tumor development, and the long period of time between primary EBV infection and development of many EBV tumors, (c) the lack of knowledge of immune correlates for protection against EBV infection and disease, (d) the limitations in animal models to study protection against EBV infection and disease, and (e) the need for additional information on the economic and societal burden of infectious mononucleosis to assess the cost-benefit of a prophylactic vaccine.
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High-dose valacyclovir decreases plasma HIV-1 RNA more than standard-dose acyclovir in persons coinfected with HIV-1 and HSV-2: a randomized crossover trial.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 04-02-2013
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Standard doses of herpes simplex virus (HSV) suppressive therapy reduce plasma HIV-1 RNA levels (0.25-0.53 log10 copies per milliliter) among HIV-1/HSV-2 coinfected persons. Postulated mechanisms for this effect include direct inhibition of HIV-1 by acyclovir or indirect reduction by decreasing HSV-associated inflammation. We hypothesized that high-dose valacyclovir would further reduce plasma HIV-1 RNA and that the effect would be mediated by greater suppression of HSV shedding.
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Immune surveillance by CD8??+ skin-resident T cells in human herpes virus infection.
Nature
PUBLISHED: 03-20-2013
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Most herpes simplex virus 2 (HSV-2) reactivations in humans are subclinical and associated with rapid expansion and containment of virus. Previous studies have shown that CD8(+) T cells persist in genital skin and mucosa at the dermal-epidermal junction (DEJ)--the portal of neuronal release of reactivating virus--for prolonged time periods after herpes lesions are cleared. The phenotype and function of this persistent CD8(+) T-cell population remain unknown. Here, using cell-type-specific laser capture microdissection, transcriptional profiling and T-cell antigen receptor ?-chain (TCR?) genotyping on sequential genital skin biopsies, we show that CD8??(+) T cells are the dominant resident population of DEJ CD8(+) T cells that persist at the site of previous HSV-2 reactivation. CD8??(+) T cells located at the DEJ lack chemokine-receptor expression required for lymphocyte egress and recirculation, express gene signatures of T-cell activation and antiviral activity, and produce cytolytic granules during clinical and virological quiescent time periods. Sequencing of the TCR ?-chain repertoire reveals that the DEJ CD8??(+) T cells are oligoclonal with diverse usage of TCR variable-? genes, which differ from those commonly described for mucosa-associated invariant T cells and natural killer T cells. Dominant clonotypes are shown to overlap among multiple recurrences over a period of two-and-a-half years. Episodes of rapid asymptomatic HSV-2 containment were also associated with a high CD8 effector-to-target ratio and focal enrichment of CD8??(+) T cells. These studies indicate that DEJ CD8??(+) T cells are tissue-resident cells that seem to have a fundamental role in immune surveillance and in initial containment of HSV-2 reactivation in human peripheral tissue. Elicitation of CD8??(+) T cells may be a critical component for developing effective vaccines against skin and mucosal infections.
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Mortality rates of human metapneumovirus and respiratory syncytial virus lower respiratory tract infections in hematopoietic cell transplantation recipients.
Biol. Blood Marrow Transplant.
PUBLISHED: 03-18-2013
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Human metapneumovirus (HMPV), a common respiratory virus, can cause severe disease in pre- and post-hematopoietic cell transplantation (HCT) recipients. We conducted a retrospective cohort analysis in HCT patients with HMPV (n = 23) or respiratory syncytial virus (n = 23) detected in bronchoalveolar lavage samples by reverse transcription PCR between 2006 and 2011 to determine disease characteristics and factors associated with outcome. Mortality rates at 100 days were 43% for both HMPV and respiratory syncytial virus lower respiratory tract disease. Steroid therapy, oxygen requirement >2 L or mechanical ventilation, and bone marrow as cell source were significant risk factors for overall and virus-related mortality in multivariable models, whereas the virus type was not. The presence of centrilobular/nodular radiographic infiltrates was a possible protective factor for mechanical ventilation. Thus, HMPV lower respiratory tract disease is associated with high mortality in HCT recipients. Earlier detection in combination with new antiviral therapy is needed to reduce mortality among HCT recipients.
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Rapid host immune response and viral dynamics in herpes simplex virus-2 infection.
Nat. Med.
PUBLISHED: 01-10-2013
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Herpes simplex virus-2 (HSV-2) is periodically shed throughout the human genital tract. Although a high viral load correlates with the development of genital ulcers, shedding also commonly occurs even when ulcers are absent, allowing for silent transmission during coitus and contributing to high seroprevalence of HSV-2 worldwide. Frequent viral reactivation occurs within ganglia despite diverse and complementary host and viral mechanisms that predispose toward latency, suggesting that viral replication may be constantly occurring in a small minority of neurons at these sites. Within genital mucosa, the in vivo expansion and clearance rates of HSV-2 are extremely rapid. Resident dendritic cells and memory HSV-2 specific T cells persist at prior sites of genital tract reactivation and, in conjunction with prompt innate recognition of infected cells, lead to rapid containment of infected cells. The fact that immune responses usually control viral replication in genital skin before lesions develop provides hope that enhancing such responses could lead to effective vaccines and immunotherapies.
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Successful isolation of infectious and high titer human monocyte-derived HIV-1 from two subjects with discontinued therapy.
PLoS ONE
PUBLISHED: 01-01-2013
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HIV-1 DNA in blood monocytes is considered a viral source of various HIV-1 infected tissue macrophages, which is also known as "Trojan horse" hypothesis. However, whether these DNA can produce virions has been an open question for years, due to the inability of isolating high titer and infectious HIV-1 directly from monocytes.
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Rapid localized spread and immunologic containment define Herpes simplex virus-2 reactivation in the human genital tract.
Elife
PUBLISHED: 01-01-2013
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Herpes simplex virus-2 (HSV-2) is shed episodically, leading to occasional genital ulcers and efficient transmission. The biology explaining highly variable shedding patterns, in an infected person over time, is poorly understood. We sampled the genital tract for HSV DNA at several time intervals and concurrently at multiple sites, and derived a spatial mathematical model to characterize dynamics of HSV-2 reactivation. The model reproduced heterogeneity in shedding episode duration and viral production, and predicted rapid early viral expansion, rapid late decay, and wide spatial dispersion of HSV replication during episodes. In simulations, HSV-2 spread locally within single ulcers to thousands of epithelial cells in <12 hr, but host immune responses eliminated infected cells in <24 hr; secondary ulcers formed following spatial propagation of cell-free HSV-2, allowing for episode prolongation. We conclude that HSV-2 infection is characterized by extremely rapid virological growth and containment at multiple contemporaneous sites within genital epithelium. DOI:http://dx.doi.org/10.7554/eLife.00288.001.
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Detection of adeno-associated virus viremia in hematopoietic cell transplant recipients.
J. Infect. Dis.
PUBLISHED: 10-17-2011
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Adeno-associated virus (AAV) is widely considered to be nonpathogenic, but the clinical epidemiology of this virus is limited. By use of polymerase chain reaction assays, we investigated the incidence and clinical significance of AAV viremia in a population of consecutive recipients of a hematopoietic cell transplant (HCT). Four (2.8%) of 145 patients developed AAV viremia after HCT. Viremia was low level and transient in all patients. Two patients were admitted to the hospital and died in proximity to AAV viremia (<7 weeks between diagnosis and death); however, AAV was not detected in tissue specimens obtained at autopsy. Thus, AAV does not appear to play a pathogenic role in organ-specific illness, even in a highly immunocompromised population.
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A Sequential Phase 2b Trial Design for Evaluating Vaccine Efficacy and Immune Correlates for Multiple HIV Vaccine Regimens.
Stat Commun Infect Dis
PUBLISHED: 09-16-2011
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Five preventative HIV vaccine efficacy trials have been conducted over the last 12 years, all of which evaluated vaccine efficacy (VE) to prevent HIV infection for a single vaccine regimen versus placebo. Now that one of these trials has supported partial VE of a prime-boost vaccine regimen, there is interest in conducting efficacy trials that simultaneously evaluate multiple prime-boost vaccine regimens against a shared placebo group in the same geographic region, for accelerating the pace of vaccine development. This article proposes such a design, which has main objectives (1) to evaluate VE of each regimen versus placebo against HIV exposures occurring near the time of the immunizations; (2) to evaluate durability of VE for each vaccine regimen showing reliable evidence for positive VE; (3) to expeditiously evaluate the immune correlates of protection if any vaccine regimen shows reliable evidence for positive VE; and (4) to compare VE among the vaccine regimens. The design uses sequential monitoring for the events of vaccine harm, non-efficacy, and high efficacy, selected to weed out poor vaccines as rapidly as possible while guarding against prematurely weeding out a vaccine that does not confer efficacy until most of the immunizations are received. The evaluation of the design shows that testing multiple vaccine regimens is important for providing a well-powered assessment of the correlation of vaccine-induced immune responses with HIV infection, and is critically important for providing a reasonably powered assessment of the value of identified correlates as surrogate endpoints for HIV infection.
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Cytopenias after day 28 in allogeneic hematopoietic cell transplantation: impact of recipient/donor factors, transplant conditions and myelotoxic drugs.
Haematologica
PUBLISHED: 08-31-2011
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Secondary cytopenias are serious complications following hematopoietic cell transplantation. Etiologies include myelotoxic agents, viral infections, and possibly transplant-related factors such as the intensity of the conditioning regimen and the source of stem cells.
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Detailed analysis of mucosal herpes simplex virus-2 replication kinetics with and without antiviral therapy.
J. Antimicrob. Chemother.
PUBLISHED: 08-24-2011
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The presence of herpes simplex virus-2 (HSV-2) shedding episodes correlates with transmission to sexual partners and neonates, and some episodes correlate with disease manifestations. HSV-2-targeted guanosine analogues are effective when given on a prophylactic basis, but do not completely eliminate recurrences, asymptomatic shedding or transmission. We sought to describe the impact of twice-daily aciclovir and famciclovir on shedding episodes.
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Impact of herpes simplex virus type 2 on HIV-1 acquisition and progression in an HIV vaccine trial (the Step study).
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 08-24-2011
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Extensive observational data suggest that herpes simplex virus type 2 (HSV-2) infection may facilitate HIV acquisition, increase HIV viral load, and accelerate HIV progression and onward transmission. To explore these relationships, we examined the impact of preexisting HSV-2 infection in an international HIV vaccine trial.
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Clinician and patient recognition of anogenital herpes disease in HIV positive men who have sex with men.
Sex Transm Dis
PUBLISHED: 08-17-2011
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Anogenital ulcers caused by herpes simplex virus type 2 (HSV-2) are associated with an increased risk of human immunodeficiency virus (HIV) transmission. When compared with clinician examination, HIV/HSV-2 coinfected men who have sex with men are frequently unaware of anogenital ulcers. These data highlight the importance of condom use and the need for new HSV-2 prevention strategies.
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Treatment with valacyclovir, famciclovir, or antiretrovirals reduces human herpesvirus-8 replication in HIV-1 seropositive men.
J. Med. Virol.
PUBLISHED: 08-13-2011
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Human herpesvirus-8 (HHV-8) replication is a key factor in Kaposi sarcoma, primary effusion lymphoma, and Castleman disease pathogenesis. In vitro data suggest that antivirals inhibit HHV-8 replication, but little data exist in humans. Daily oropharyngeal swabs were analyzed from HIV/HHV-8 dually infected men enrolled in three previous clinical trials of valacyclovir and famciclovir for HIV-1 and/or HSV-2 suppression. Fifty-eight participants contributed 6,036 swabs. HHV-8 was detected in 1,128 (19%) of 6,036 swabs, including 618 (21%) of 2,992 on placebo, 323 (15%) of 2,221 on valacyclovir, and 187 (23%) of 823 on famciclovir. After adjusting for baseline HIV viral load and highly active antiretroviral therapy (HAART) use, an 18% reduction in HHV-8 shedding frequency (IRR 0.822; P?=?0.011) was found in participants on valacyclovir and a 30% reduction (IRR 0.700; P?
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The kinetics of mucosal herpes simplex virus-2 infection in humans: evidence for rapid viral-host interactions.
J. Infect. Dis.
PUBLISHED: 07-28-2011
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Herpes simplex virus type 2 (HSV-2) reactivations in the genital tract are responsible for mucocutaneous lesions and transmission and manifest as discrete shedding episodes.
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Safety and efficacy of the HVTN 503/Phambili study of a clade-B-based HIV-1 vaccine in South Africa: a double-blind, randomised, placebo-controlled test-of-concept phase 2b study.
Lancet Infect Dis
PUBLISHED: 05-11-2011
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The MRKAd5 HIV-1 gag/pol/nef subtype B vaccine was designed to elicit T-cell-mediated immune responses capable of providing complete or partial protection from HIV-1 infection or a decrease in viral load after acquisition. We aim to assess the safety and efficacy of the vaccine in South Africa, where the major circulating clade is subtype C.
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Serological immunity to adenovirus serotype 5 is not associated with risk of HIV infection: a case-control study.
AIDS
PUBLISHED: 05-07-2011
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adenoviruses are among the most promising vectors for the development of an HIV vaccine. The results of the phase IIB study of the adenovirus serotype 5-based Merck Trivalent HIV vaccine have raised the concern that serological immunity to adenovirus serotype 5 (Ad5) could be linked to HIV acquisition risk in high-risk individuals. We examined the association between adenovirus serostatus and the rate of incident HIV infection in populations at elevated risk of HIV acquisition.
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HIV-1 vaccines and adaptive trial designs.
Sci Transl Med
PUBLISHED: 04-22-2011
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Developing a vaccine against the human immunodeficiency virus (HIV) poses an exceptional challenge. There are no documented cases of immune-mediated clearance of HIV from an infected individual, and no known correlates of immune protection. Although nonhuman primate models of lentivirus infection have provided valuable data about HIV pathogenesis, such models do not predict HIV vaccine efficacy in humans. The combined lack of a predictive animal model and undefined biomarkers of immune protection against HIV necessitate that vaccines to this pathogen be tested directly in clinical trials. Adaptive clinical trial designs can accelerate vaccine development by rapidly screening out poor vaccines while extending the evaluation of efficacious ones, improving the characterization of promising vaccine candidates and the identification of correlates of immune protection.
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Valganciclovir reduces T cell activation in HIV-infected individuals with incomplete CD4+ T cell recovery on antiretroviral therapy.
J. Infect. Dis.
PUBLISHED: 04-20-2011
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Elevated immune activation persists during treated human immunodeficiency virus (HIV) infection and is associated with blunted CD4 recovery and premature mortality, but its causes remain incompletely characterized. We hypothesized that asymptomatic cytomegalovirus (CMV) replication might contribute to immune activation in this setting.
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Genital shedding of herpes simplex virus among symptomatic and asymptomatic persons with HSV-2 infection.
JAMA
PUBLISHED: 04-14-2011
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Since herpes simplex virus type 2 (HSV-2) antibody tests have become commercially available, an increasing number of persons have learned that they have genital herpes through serologic testing. The course of natural history of HSV-2 in asymptomatic, seropositive persons is uncertain.
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Genital HIV-1 RNA predicts risk of heterosexual HIV-1 transmission.
Sci Transl Med
PUBLISHED: 04-08-2011
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High plasma HIV-1 RNA concentrations are associated with an increased risk of HIV-1 transmission. Although plasma and genital HIV-1 RNA concentrations are correlated, no study has evaluated the relationship between genital HIV-1 RNA and the risk of heterosexual HIV-1 transmission. In a prospective study of 2521 African HIV-1 serodiscordant couples, we assessed genital HIV-1 RNA quantity and HIV-1 transmission risk. HIV-1 transmission linkage was established within the partnership by viral sequence analysis. We tested endocervical samples from 1805 women, including 46 who transmitted HIV-1 to their partner, and semen samples from 716 men, including 32 who transmitted HIV-1 to their partner. There was a correlation between genital and plasma HIV-1 RNA concentrations: For endocervical swabs, Spearmans rank correlation coefficient ? was 0.56, and for semen, ? was 0.55. Each 1.0 log(10) increase in genital HIV-1 RNA was associated with a 2.20-fold (for endocervical swabs: 95% confidence interval, 1.60 to 3.04) and a 1.79-fold (for semen: 95% confidence interval, 1.30 to 2.47) increased risk of HIV-1 transmission. Genital HIV-1 RNA independently predicted HIV-1 transmission risk after adjusting for plasma HIV-1 quantity (hazard ratio, 1.67 for endocervical swabs and 1.68 for semen). Seven female-to-male and four male-to-female HIV-1 transmissions (incidence <1% per year) occurred from persons with undetectable genital HIV-1 RNA, but in all 11 cases, plasma HIV-1 RNA was detected. Thus, higher genital HIV-1 RNA concentrations are associated with greater risk of heterosexual HIV-1 transmission, and this effect was independent of plasma HIV-1 concentrations. These data suggest that HIV-1 RNA in genital secretions could be used as a marker of HIV-1 sexual transmission risk.
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H275Y mutant pandemic (H1N1) 2009 virus in immunocompromised patients.
Emerging Infect. Dis.
PUBLISHED: 04-08-2011
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Most oseltamivir-resistant pandemic (H1N1) 2009 viruses have been isolated from immunocompromised patients. To describe the clinical features, treatment, outcomes, and virologic data associated with infection from pandemic (H1N1) 2009 virus with H275Y mutation in immunocompromised patients, we retrospectively identified 49 hematology-oncology patients infected with pandemic (H1N1) 2009 virus. Samples from 33 of those patients were tested for H275Y genotype by allele-specific real-time PCR. Of the 8 patients in whom H275Y mutations was identified, 1 had severe pneumonia; 3 had mild pneumonia with prolonged virus shedding; and 4 had upper respiratory tract infection, of whom 3 had prolonged virus shedding. All patients had received oseltamivir before the H275Y mutation was detected; 1 had received antiviral prophylaxis. Three patients excreted resistant virus for >60 days. Emergence of oseltamivir resistance is frequent in immunocompromised patients infected with pandemic (H1N1) 2009 virus and can be associated with a wide range of clinical disease and viral kinetics.
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A trimeric, V2-deleted HIV-1 envelope glycoprotein vaccine elicits potent neutralizing antibodies but limited breadth of neutralization in human volunteers.
J. Infect. Dis.
PUBLISHED: 04-01-2011
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A key missing element in the development of a successful human immunodeficiency virus (HIV) vaccine is an immunogen that can generate broadly cross-neutralizing antibodies against primary isolates of the virus.
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Xenotropic murine leukemia virus-related virus in monozygotic twins discordant for chronic fatigue syndrome.
Diagn. Microbiol. Infect. Dis.
PUBLISHED: 03-23-2011
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A recent report suggested an association between xenotropic murine leukemia virus-related virus (XMRV) and chronic fatigue syndrome (CFS). If confirmed, this would suggest that antiretroviral therapy might benefit patients suffering from CFS. We validated a set of assays for XMRV and evaluated the prevalence of XMRV in a cohort of monozygotic twins discordant for CFS. Stored peripheral blood mononuclear cell (PBMC) samples were tested with 3 separate polymerase chain reaction (PCR) assays (one of which was nested) for XMRV DNA, and serum/plasma was tested for XMRV RNA by reverse transcription (RT)-PCR. None of the PBMC samples from the twins with CFS or their unaffected co-twins was positive for XMRV, by any of the assays. One plasma sample, from an unaffected co-twin, was reproducibly positive by RT-PCR. However, serum from the same day was negative, as was a follow-up plasma sample obtained 2 days after the positive specimen. These data do not support an association of XMRV with CFS.
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Cytomegalovirus viremia as a risk factor for mortality prior to antiretroviral therapy among HIV-infected gold miners in South Africa.
PLoS ONE
PUBLISHED: 03-22-2011
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Cytomegalovirus (CMV) viremia has been shown to be an independent risk factor for increased mortality among HIV-infected individuals in the developing world. While CMV infection is nearly ubiquitous in resource-poor settings, few data are available on the role of subclinical CMV reactivation on HIV.
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HIV-specific CD8+ T cells from HIV+ individuals receiving HAART can be expanded ex vivo to augment systemic and mucosal immunity in vivo.
Blood
PUBLISHED: 03-21-2011
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Most HIV+ individuals require lifelong highly active antiretroviral therapy (HAART) to suppress HIV replication, but fail to eliminate the virus in part because of residual replication in gut-associated lymphoid tissues (GALT). Naturally elicited HIV-specific CD8+ T cells generated in the acute and chronic infectious phases exhibit antiviral activity, but decrease in number after HAART. Therapeutic vaccines represent a potential strategy to expand cellular responses, although previous efforts have been largely unsuccessful, conceivably because of a lack of responding HIV-specific central-memory CD8+ T cells (Tcm). To determine whether patients receiving HAART possess CD8+ T cells with Tcm qualities that are amenable to augmentation, HIV-specific CD8+ T-cell clones were derived from HIV-reactive CD28+CD8+ T-cell lines isolated from 7 HIV+ HAART-treated patients, expanded ex vivo, and reinfused into their autologous host. Tracking of the cells in vivo revealed that clones could persist for ? 84 days, maintain expression and/or re-express CD28, up-regulate CD62L, secrete IL-2, proliferate on cognate Ag encounter and localize to the rectal mucosa. These results suggest some infused cells exhibited phenotypic and functional characteristics shared with Tcm in vivo, and imply that more effective therapeutic vaccination strategies targeting CD8+ Tcm in patients on HAART might provide hosts with expanded, long-lasting immune responses not only systemically but also in GALT.
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The HIV protease inhibitor nelfinavir inhibits Kaposis sarcoma-associated herpesvirus replication in vitro.
Antimicrob. Agents Chemother.
PUBLISHED: 03-14-2011
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Kaposis sarcoma (KS) is the most common HIV-associated cancer worldwide and is associated with high levels of morbidity and mortality in some regions. Antiretroviral (ARV) combination regimens have had mixed results for KS progression and resolution. Anecdotal case reports suggest that protease inhibitors (PIs) may have effects against KS that are independent of their effect on HIV infection. As such, we evaluated whether PIs or other ARVs directly inhibit replication of Kaposis sarcoma-associated herpesvirus (KSHV), the gammaherpesvirus that causes KS. Among a broad panel of ARVs tested, only the PI nelfinavir consistently displayed potent inhibitory activity against KSHV in vitro as demonstrated by an efficient quantitative assay for infectious KSHV using a recombinant virus, rKSHV.294, which expresses the secreted alkaline phosphatase. This inhibitory activity of nelfinavir against KSHV replication was confirmed using virus derived from a second primary effusion lymphoma cell line. Nelfinavir was similarly found to inhibit in vitro replication of an alphaherpesvirus (herpes simplex virus) and a betaherpesvirus (human cytomegalovirus). No activity was observed with nelfinavir against vaccinia virus or adenovirus. Nelfinavir may provide unique benefits for the prevention or treatment of HIV-associated KS and potentially other human herpesviruses by direct inhibition of replication.
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HHV-6 reactivation and its effect on delirium and cognitive functioning in hematopoietic cell transplantation recipients.
Blood
PUBLISHED: 03-09-2011
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Human herpesvirus 6 (HHV-6) is detected in the plasma of approximately 40% of patients undergoing hematopoietic cell transplantation (HCT) and sporadically causes encephalitis in this population. The effect of HHV-6 reactivation on central nervous system function has not been fully characterized. This prospective study aimed to evaluate associations between HHV-6 reactivation and central nervous system dysfunction after allogeneic HCT. Patients were enrolled before HCT. Plasma samples were tested for HHV-6 at baseline and twice weekly after transplantation until day 84. Delirium was assessed at baseline, 3 times weekly until day 56, and weekly on days 56 to 84 using a validated instrument. Neurocognitive testing was performed at baseline and at approximately day 84. HHV-6 was detected in 111 (35%) of the 315 included patients. Patients with HHV-6 were more likely to develop delirium (adjusted odds ratio = 2.5; 95% confidence interval, 1.2-5.3) and demonstrate neurocognitive decline (adjusted odds ratio = 2.6; 95% confidence interval, 1.1-6.2) in the first 84 days after HCT. Cord blood and unrelated transplantation increased risk of HHV-6 reactivation. These data provide the basis to conduct a randomized clinical trial to determine whether prevention of HHV-6 reactivation will reduce neurocognitive morbidity in HCT recipients.
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Mapping HIV-1 vaccine induced T-cell responses: bias towards less-conserved regions and potential impact on vaccine efficacy in the Step study.
PLoS ONE
PUBLISHED: 03-05-2011
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T cell directed HIV vaccines are based upon the induction of CD8+ T cell memory responses that would be effective in inhibiting infection and subsequent replication of an infecting HIV-1 strain, a process that requires a match or near-match between the epitope induced by vaccination and the infecting viral strain. We compared the frequency and specificity of the CTL epitope responses elicited by the replication-defective Ad5 gag/pol/nef vaccine used in the Step trial with the likelihood of encountering those epitopes among recently sequenced Clade B isolates of HIV-1. Among vaccinees with detectable 15-mer peptide pool ELISpot responses, there was a median of four (one Gag, one Nef and two Pol) CD8 epitopes per vaccinee detected by 9-mer peptide ELISpot assay. Importantly, frequency analysis of the mapped epitopes indicated that there was a significant skewing of the T cell response; variable epitopes were detected more frequently than would be expected from an unbiased sampling of the vaccine sequences. Correspondingly, the most highly conserved epitopes in Gag, Pol, and Nef (defined by presence in >80% of sequences currently in the Los Alamos database www.hiv.lanl.gov) were detected at a lower frequency than unbiased sampling, similar to the frequency reported for responses to natural infection, suggesting potential epitope masking of these responses. This may be a generic mechanism used by the virus in both contexts to escape effective T cell immune surveillance. The disappointing results of the Step trial raise the bar for future HIV vaccine candidates. This report highlights the bias towards less-conserved epitopes present in the same vaccine used in the Step trial. Development of vaccine strategies that can elicit a greater breadth of responses, and towards conserved regions of the genome in particular, are critical requirements for effective T-cell based vaccines against HIV-1. Trial registration: ClinicalTrials.gov NCT00849680, A Study of Safety, Tolerability, and Immunogenicity of the MRKAd5 Gag/Pol/Nef Vaccine in Healthy Adults.
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Differences in clinical outcomes after 2009 influenza A/H1N1 and seasonal influenza among hematopoietic cell transplant recipients.
Blood
PUBLISHED: 03-03-2011
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It is not known whether pandemic 2009 influenza A/H1N1 (2009 H1N1) leads to more serious disease than seasonal influenza in hematopoietic cell transplant (HCT) recipients. In a retrospective study in HCT recipients with virologically proven influenza virus infection, a total of 161 HCT recipients (18 2009 H1N1, 103 seasonal influenza A, and 40 seasonal influenza B) were analyzed. In multivariable analyses, more patients with 2009 H1N1 had lower respiratory tract disease (LRD), hypoxemia, and prolonged viral shedding compared with seasonal influenza A. Seasonal influenza A and B outcomes were similar. There was no difference in overall and influenza-associated mortality among influenza virus types. Both early and delayed administration of antiviral therapy was shown to be beneficial in terms of decreased rates of development of LRD, although earlier intervention appeared to be more effective. Profound lymphopenia and lack of early antiviral therapy were associated significantly with LRD, hypoxemia, and death. High-dose corticosteroid treatment (? 1 mg/kg) given at the time of influenza diagnosis was associated with a reduced risk for mechanical ventilation. Thus, our data suggest that infection with 2009 influenza A/H1N1 resulted in more severe respiratory disease in HCT recipients compared with seasonal influenza.
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A phase IIA randomized clinical trial of a multiclade HIV-1 DNA prime followed by a multiclade rAd5 HIV-1 vaccine boost in healthy adults (HVTN204).
PLoS ONE
PUBLISHED: 03-01-2011
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The safety and immunogenicity of a vaccine regimen consisting of a 6-plasmid HIV-1 DNA prime (envA, envB, envC, gagB, polB, nefB) boosted by a recombinant adenovirus serotype-5 (rAd5) HIV-1 with matching inserts was evaluated in HIV-seronegative participants from South Africa, United States, Latin America and the Caribbean.
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Introduction of a novel parechovirus RT-PCR clinical test in a regional medical center.
J. Clin. Virol.
PUBLISHED: 02-07-2011
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Although data documenting the severity and frequency of human parechovirus (HPeV) infections have been published, detection of HPeV is not routinely performed in most clinical virology laboratories.
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Genetic impact of vaccination on breakthrough HIV-1 sequences from the STEP trial.
Nat. Med.
PUBLISHED: 01-31-2011
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We analyzed HIV-1 genome sequences from 68 newly infected volunteers in the STEP HIV-1 vaccine trial. To determine whether the vaccine exerted selective T cell pressure on breakthrough viruses, we identified potential T cell epitopes in the founder sequences and compared them to epitopes in the vaccine. We found greater distances to the vaccine sequence for sequences from vaccine recipients than from placebo recipients. The most significant signature site distinguishing vaccine from placebo recipients was Gag amino acid 84, a site encompassed by several epitopes contained in the vaccine and restricted by human leukocyte antigen (HLA) alleles common in the study cohort. Moreover, the extended divergence was confined to the vaccine components of the virus (HIV-1 Gag, Pol and Nef) and not found in other HIV-1 proteins. These results represent what is to our knowledge the first evidence of selective pressure from vaccine-induced T cell responses on HIV-1 infection in humans.
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Viral linkage in HIV-1 seroconverters and their partners in an HIV-1 prevention clinical trial.
PLoS ONE
PUBLISHED: 01-18-2011
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Characterization of viruses in HIV-1 transmission pairs will help identify biological determinants of infectiousness and evaluate candidate interventions to reduce transmission. Although HIV-1 sequencing is frequently used to substantiate linkage between newly HIV-1 infected individuals and their sexual partners in epidemiologic and forensic studies, viral sequencing is seldom applied in HIV-1 prevention trials. The Partners in Prevention HSV/HIV Transmission Study (ClinicalTrials.gov #NCT00194519) was a prospective randomized placebo-controlled trial that enrolled serodiscordant heterosexual couples to determine the efficacy of genital herpes suppression in reducing HIV-1 transmission; as part of the study analysis, HIV-1 sequences were examined for genetic linkage between seroconverters and their enrolled partners.
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Genital HSV detection among HIV-1-infected pregnant women in labor.
Infect Dis Obstet Gynecol
PUBLISHED: 01-13-2011
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To compare genital HSV shedding among HIV-positive and HIV-negative women.
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Herpes simplex virus type 2 suppressive therapy with acyclovir or valacyclovir does not select for specific HIV-1 resistance in HIV-1/HSV-2 dually infected persons.
J. Infect. Dis.
PUBLISHED: 01-12-2011
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Recent in vitro studies suggest that acyclovir may directly inhibit HIV-1 replication and can select for a specific HIV-1 reverse transcriptase mutation (V75I) with concomitant loss of an anti-HIV-1 effect. We tested for HIV-1 genotypic resistance at reverse transcriptase codon 75 in plasma from 168 HIV-1-infected persons from Botswana, Kenya, Peru, and the United States taking daily acyclovir or valacyclovir for between 8 weeks and 24 months. No V75I cases were detected (95% confidence interval, 0%-2.2%). These prospective in vivo studies suggest that standard-dose acyclovir or valacyclovir does not select for HIV-1 resistance.
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Development of an interferon-gamma ELISPOT assay to detect human T cell responses to HSV-2.
Vaccine
PUBLISHED: 01-11-2011
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The need for an HSV-2 vaccine is great considering the increasing prevalence of HSV-2 despite the widespread use of antiviral drugs. Human clinical trials of HSV-2 vaccines that elicit neutralizing antibodies have proven to be only partially effective suggesting that induction of effective T cell responses to HSV-2 is also a critical component to an efficacious vaccine. A sensitive and specific assay to measure HSV-specific T cell responses is a necessary part of vaccine development and thus we undertook the development of an interferon-? (IFN-?) ELISPOT assay to measure T cell responses to HSV-2.
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A phase I trial of preventive HIV vaccination with heterologous poxviral-vectors containing matching HIV-1 inserts in healthy HIV-uninfected subjects.
Vaccine
PUBLISHED: 01-07-2011
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We evaluated replication-defective poxvirus vectors (modified vaccinia Ankara [MVA] and fowlpox [FPV]) in a homologous and heterologous vector prime-boost vaccination regimen containing matching HIV inserts (MVA-HIV and FPV-HIV) given at months 0, 1, 3, 5 and 7 in 150 healthy HIV-negative vaccinia-naïve participants. FPV-HIV alone was poorly immunogenic, while the high dose (10(9)pfu/2 ml) of MVA-HIV alone elicited maximal responses after two injections: CD4+ and CD8+ T-cell responses in 26/55 (47.3%) and 5/60 (8.3%) of participants, respectively, and IFN-? ELISpot responses in 28/62 (45.2%). The infrequent CD8+ T-cell responses following MVA-HIV priming were boosted only by the heterologous (FPV-HIV) construct in 14/27 (51.9%) of participants post 4th vaccination. Alternatively, HIV envelope-specific binding antibodies were demonstrated in approximately two-thirds of recipients of the homologous boosting regimen, but in less than 20% of subjects after the heterologous vector boost. Thus, a heterologous poxvirus vector prime-boost regimen can induce HIV-specific CD8+ T-cell and CD4+ T-cell responses, which may be an important feature of an optimal regimen for preventive HIV vaccination.
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Persistent genital herpes simplex virus-2 shedding years following the first clinical episode.
J. Infect. Dis.
PUBLISHED: 12-09-2010
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Patients with newly acquired genital herpes simplex virus 2 (HSV-2) infection have virus frequently detected at the genital mucosa. Rates of genital shedding initially decrease over time after infection, but data on long-term viral shedding are lacking.
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Mucosal host immune response predicts the severity and duration of herpes simplex virus-2 genital tract shedding episodes.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 10-18-2010
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Herpes simplex virus-2 (HSV-2) shedding episodes in humans vary markedly in duration and virologic titer within an infected person over time, an observation that is unexplained. To evaluate whether host or virological factors more closely accounted for this variability, we combined measures of viral replication and CD8(+) lymphocyte density in genital biopsies, with a stochastic mathematical model of HSV-2 infection. Model simulations reproduced quantities of virus and duration of shedding detected in 1,003 episodes among 386 persons. In the simulations, local CD8(+) lymphocyte density in the mucosa at episode onset predicted peak HSV DNA copy number and whether genital lesions or subclinical shedding occurred. High density of CD8(+) T cells in the mucosa correlated with decreased infected cell lifespan and fewer infected epithelial cells before episode clearance. If infected cell lifespan increased by 15 min because of CD8(+) lymphocyte decay, then there was potential for a thousandfold increase in the number of infected cells. The model suggests that the rate of containment of infected cells by the peripheral mucosal immune system is the major driver of duration and severity of HSV-2 reactivation in the immunocompetent host.
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Impact of corticosteroid treatment and antiviral therapy on clinical outcomes in hematopoietic cell transplant patients infected with influenza virus.
Biol. Blood Marrow Transplant.
PUBLISHED: 07-31-2010
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The impact of cytokines induced during influenza infection has been described, but the effect of corticosteroids on clinical outcomes is unclear. Although antiviral therapy has been well studied in immunocompetent subjects, few data exist on its clinical efficacy in immunocompromised populations. Data from 143 hematopoietic cell transplant recipients with documented seasonal influenza infection were reviewed to examine the impact of different corticosteroid regimens and antiviral therapy on clinical outcomes. In multivariable analyses, there was no observed difference between patients who received no, low doses (<1 mg/kg/day), or high doses (? 1 mg/kg/day) of corticosteroids with regard to the development of lower respiratory tract disease (LRD), hypoxemia, need for mechanical ventilation, or death. However, treatment with high-dose steroids was associated with a trend toward prolonged viral shedding (odds ratio [OR], 3.3; 95% confidence interval [CI], 1.0-11; P = .05). In multivariable analyses, antiviral therapy initiated to treat upper respiratory tract infection (URI) was associated with fewer cases of LRD (OR, 0.04; 95% CI, 0-0.2; P < .01) and fewer hypoxemia episodes (OR, 0.3; 95% CI, 0.1-0.9; P = .03). Our results suggest that corticosteroids are not associated with adverse clinical outcomes in hematopoietic cell transplant recipients infected with influenza, although use of higher doses may delay viral clearance. Antiviral therapy initiated during the URI phase reduced the risk of LRD and hypoxemia.
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Rapidly cleared episodes of oral and anogenital herpes simplex virus shedding in HIV-infected adults.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 07-10-2010
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To determine whether rapidly cleared episodes of herpes simplex virus (HSV) reactivation occur in HIV-infected adults.
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Subclinical viremia increases risk for chronic allograft injury in pediatric renal transplantation.
J. Am. Soc. Nephrol.
PUBLISHED: 07-08-2010
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The impact of subclinical viral infection on chronic allograft injury in the pediatric renal transplant population is not well defined. We prospectively assessed cytomegalovirus (CMV) and Epstein-Barr virus (EBV) DNAemia by monthly PCR in 55 pediatric renal transplant recipients for the first 2 years after transplantation. Subclinical CMV and EBV infection occurred in 22 and 36%, respectively. Multivariable linear regression analysis suggested that both subclinical CMV and EBV infection independently associate with significant declines in GFR during the first 2 years after transplantation. CMV seronegativity associated with a significantly greater decline in GFR than seropositivity (P < 0.01). Subclinical CMV infection and subclinical EBV infection each associated with approximately fourfold greater odds of histologic evidence of chronic allograft injury (odds ratio 4.61 [95% confidence interval 1.18 to 18.07] and odds ratio 4.33 [95% confidence interval 1.34 to 14.00], respectively). An increase in viral load of CMV or EBV also associated with increased risk for moderate to severe chronic allograft injury. Taken together, these results demonstrate an association between subclinical CMV and EBV infections, which occur despite standard antiviral prophylaxis, and chronic allograft injury in pediatric renal transplant recipients.
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Cervicovaginal shedding of hepatitis C viral RNA is associated with the presence of menstrual or other blood in cervicovaginal fluids.
J. Clin. Virol.
PUBLISHED: 06-25-2010
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The role of sexual activity in hepatitis C virus (HCV) transmission remains controversial. Studies to date have not explored the relationship between HCV shedding in cervicovaginal fluids and the presence of menstrual or other blood.
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Estimating the impact of plasma HIV-1 RNA reductions on heterosexual HIV-1 transmission risk.
PLoS ONE
PUBLISHED: 06-10-2010
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The risk of sexual transmission of HIV-1 is strongly associated with the level of HIV-1 RNA in plasma making reduction in HIV-1 plasma levels an important target for HIV-1 prevention interventions. A quantitative understanding of the relationship of plasma HIV-1 RNA and HIV-1 transmission risk could help predict the impact of candidate HIV-1 prevention interventions that operate by reducing plasma HIV-1 levels, such as antiretroviral therapy (ART), therapeutic vaccines, and other non-ART interventions.
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Diversity in CD8(+) T cell function and epitope breadth among persons with genital herpes.
J. Clin. Immunol.
PUBLISHED: 05-27-2010
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CD8(+) T cells are known to be important in clearing herpes simplex virus (HSV) infections. However, investigating the specific antiviral mechanisms employed by HSV-2-specific T cell populations is limited by a lack of reagents such as CD8(+) T cell epitopes and specific tetramers. Using a combination of intracellular cytokine staining flow cytometry and ELISpot methods, we functionally characterized peripheral HSV-2-specific CD8(+) T cells from peripheral blood mononuclear cell (PBMC) that recognize 14 selected HSV-2 open-reading frames (ORFs) from 55 HSV-2 seropositive persons; within these ORFs, we subsequently identified more than 20 unique CD8(+) T cell epitopes. CD8(+) T cells to HSV-2 exhibited significant heterogeneity in their functional characteristics, proliferation, production of inflammatory cytokines, and potential to degranulate ex vivo. The diversity in T cell response in these ex vivo assessments offers the potential of defining immune correlates of HSV-2 reactivation in humans.
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Rapid polymerase chain reaction assay to detect herpes simplex virus in the genital tract of women in labor.
Obstet Gynecol
PUBLISHED: 05-27-2010
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To develop a rapid quantitative real-time polymerase chain reaction (PCR) to detect herpes simplex virus (HSV) in the genital secretions of women that may be used in labor.
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Gender differences in clinical presentation and outcomes of epidemic Kaposi sarcoma in Uganda.
PLoS ONE
PUBLISHED: 04-07-2010
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The incidence of Kaposi sarcoma (KS) has increased dramatically among women in sub-Saharan Africa since the onset of the HIV pandemic, but data on KS disease in women are limited. To identify gender-related differences in KS presentation and outcomes, we evaluated the clinical manifestations and response in men and women with AIDS-associated KS in Uganda.
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Population level impact of an imperfect prophylactic vaccine for herpes simplex virus-2.
Sex Transm Dis
PUBLISHED: 03-31-2010
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The continuation of developing Herpes simplex virus type-2 (HSV-2) prophylactic vaccines requires parallel mathematical modeling to quantify the effect on the population of these vaccines.
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Respiratory virus pneumonia after hematopoietic cell transplantation (HCT): associations between viral load in bronchoalveolar lavage samples, viral RNA detection in serum samples, and clinical outcomes of HCT.
J. Infect. Dis.
PUBLISHED: 03-31-2010
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Few data exist on respiratory virus quantitation in lower respiratory samples and detection in serum from hematopoietic cell transplant (HCT) recipients with respiratory virus-associated pneumonia.
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Clinical and virologic efficacy of herpes simplex virus type 2 suppression by acyclovir in a multicontinent clinical trial.
J. Infect. Dis.
PUBLISHED: 03-11-2010
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Acyclovir suppressive therapy (400 mg twice daily) reduces herpes simplex virus (HSV) type 2-associated genital ulcer disease and lesional HSV shedding. In an international trial of acyclovir for suppression of HSV type 2 to prevent human immunodeficiency virus (HIV) acquisition (HIV Prevention Trials Network 039), acyclovir had a smaller effect on the frequency of genital ulcer disease as well as a smaller effect on the frequency and quantity of lesional HSV DNA in African women and Peruvian men, compared with its effects in men in the United States. The observed regional variation in the clinical and virologic efficacy of acyclovir for HSV suppression warrants further evaluation of determinants of responses to acyclovir. (ClinicalTrials.gov identifier: NCT00076232.).
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Clinical presentation and outcome of epidemic Kaposi sarcoma in Ugandan children.
Pediatr Blood Cancer
PUBLISHED: 03-06-2010
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Kaposi sarcoma (KS) is one of the most common pediatric cancers in sub-Saharan Africa. Few data are available about the clinical presentation or response to treatment of children with epidemic (HIV-associated) KS.
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Detailed characterization of T cell responses to herpes simplex virus-2 in immune seronegative persons.
J. Immunol.
PUBLISHED: 02-17-2010
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In 2003, we described a small cohort of subjects (n = 6) who possessed no detectable serum Abs to HSV-1 or HSV-2 and no clinical or virological evidence of mucosal HSV infection yet possessed consistently detectable HSV-specific T cell responses measured primarily by lymphoproliferative (LP) and CTL assays to whole HSV-2 Ag. We termed these persons immune seronegative (IS). This report characterizes the T cell responses in 22 IS subjects largely recruited from studies of HSV-seronegative subjects in ongoing sexual relationships with HSV-2-seropositive (HSV-2(+)) partners using pools of overlapping peptides spanning 16 immuno-prevalent HSV-2 proteins. Overall, 77% of IS subjects had HSV-specific LP responses, 85% had IFN-gamma ELISPOT responses to at least one HSV-2 peptide pool, and 55% had both LP and IFN-gamma ELISPOT responses. In some cases, IFN-gamma ELISPOT responses were in excess of 500 spot-forming cells per 10(6) PBMCs and persisted for over 5 y. Although HSV-2(+) subjects (n = 40) had frequent responses to glycoproteins and tegument and immediate-early (IE) proteins of HSV-2, T cell responses in IS subjects were directed primarily at UL39 and the IE proteins ICP4 and ICP0. These data suggest that the antigenic repertoire of T cells in IS subjects is skewed compared with that of HSV-2(+) subjects and that IS subjects had more frequent T cell responses to IE proteins and infrequent T cell responses to virion components. Understanding the mechanism(s) by which such responses are elicited may provide important insights in developing novel strategies for preventing acquisition of sexually acquired HSV-2.
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In situ detection of Gag-specific CD8+ cells in the GI tract of SIV infected Rhesus macaques.
Retrovirology
PUBLISHED: 02-16-2010
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SIV and HIV predominantly replicate in lymphoid tissue, but the study of virus specific CD8+ T cells in intact lymphoid tissue is difficult, as traditional in situ tetramer staining requires fresh tissue.
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Frequent detection of human adenovirus from the lower gastrointestinal tract in men who have sex with men.
PLoS ONE
PUBLISHED: 02-04-2010
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The association between baseline seropositivity to human adenovirus (HAdV) type 5 and increased HIV acquisition in the Step HIV Vaccine Study has raised questions concerning frequency of acquired and/or persistent Adenovirus infections among adults at high risk of HIV-1 infection.
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Overlapping reactivations of herpes simplex virus type 2 in the genital and perianal mucosa.
J. Infect. Dis.
PUBLISHED: 01-22-2010
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Genital shedding of herpes simplex virus (HSV) type 2 occurs frequently. Anatomic patterns of genital HSV-2 reactivation have not been intensively studied.
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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.