133 research outputs found

    Frequency and implications of HIV superinfection

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    HIV superinfection occurs when an individual with HIV is infected with a new distinct HIV viral strain. Superinfection has been reported throughout the world, and studies have recorded incidence rates of 0–7·7% per year. Use of next-generation sequencing has improved detection of superinfection, which can be transmitted by injecting drug use and sexual intercourse. Superinfection might have incidence rates comparable to those of initial HIV infection. Clinicians should encourage safe sexual and injecting drug use practices for HIV-infected patients because superinfection has detrimental effects on clinical outcomes and could pose a concern for large-scale antiretroviral treatment plans. The occurrence of superinfection has implications for vaccine research, since it seems initial HIV infection is not fully protective against a subsequent infection. Additional collaborative research could benefit care of patients and inform future vaccine design

    Deep sequencing of the HIV‑1 polymerase gene for characterisation of cytotoxic T‑lymphocyte epitopes during early and chronic disease stages

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    BACKGROUND : Despite multiple attempts, there is still no effective HIV-1 vaccine available. The HIV-1 polymerase (pol) gene is highly conserved and encodes cytotoxic T-lymphocyte (CTL) epitopes. The aim of the study was to characterise HIV-1 Pol CTL epitopes in mostly sample pairs obtained during early and chronic stages of infection. METHODS : Illumina deep sequencing was performed for all samples while Sanger sequencing was only performed on baseline samples. Codons under immune selection pressure were assessed by computing nonsynonymous to synonymous mutation ratios using MEGA. Minority CTL epitope variants occurring at 5% were detected using lowfrequency variant tool in CLC Genomics. Los Alamos HIV database was used for mapping mutations to known HIV-1 CTL epitopes. RESULTS : Fifty-two participants were enrolled in the study. Their median age was 28 years (interquartile range: 24–32 years) and majority of participants (92.3%) were female. Illumina minority variant analysis identified a significantly higher number of CTL epitopes (n = 65) compared to epitopes (n = 8) identified through Sanger sequencing. Most of the identified epitopes mapped to reverse transcriptase (RT) and integrase (IN) regardless of sequencing method. There was a significantly higher proportion of minority variant epitopes in RT (n = 39, 60.0%) compared to IN (n = 17, 26.2%) and PR (n = 9, 13.8%), p = 0.002 and < 0.0001, respectively. However, no significant difference was observed between the proportion of minority variant epitopes in IN versus PR, p = 0.06. Some epitopes were detected in either early or chronic HIV-1 infection whereas others were detected in both stages. Different distribution patterns of minority variant epitopes were observed in sample pairs; with some increasing or decreasing over time, while others remained constant. Some of the identified epitopes have not been previously reported for HIV-1 subtype C. There were also variants that could not be mapped to reported CTL epitopes in the Los Alamos HIV database. CONCLUSION : Deep sequencing revealed many Pol CTL epitopes, including some not previously reported for HIV-1 subtype C. The findings of this study support the inclusion of RT and IN epitopes in HIV-1 vaccine candidates as these proteins harbour many CTL epitopes.Additional file 1. Supplementary Table 1: The in-house complete HIV pol nested PCR conditions and Sanger sequencing primers.Additional file 2. Supplementary Table 2: Pol CTL epitopes identified through Sanger sequencing and comparison by stage of infectionAdditional file 3. Supplementary Table 3: Minority variant proportions within Pol CTL epitopes by stage of infection.Additional file 4. Supplementary Figure 1: Neighbour-joining phylogenetic analysis of Illumina consensus and Sanger consensus sequences for baseline samples. Sanger and Illumina consensus of the same sample significantly clustered together. Majority of the sequences clustered with HIV-1 subtype C references. HIV group O was used for rooting the tree and a bootstrap value of 1000 was used for analysis. S = Sanger sequencing; D = Deep sequencing.The National Research Foundation of South Africa; Poliomyelitis Research Foundation (PRF); Discovery Foundation; National Health Laboratory Service Research Trust (NHLS-RT); South African Medical Research Council Self-Initiated Research (MRC-SIR); University of Pretoria Faculty of Health Sciences Research Committee; the South African Research Chairs Initiative of the Department of Science and Innovation and ADR—The Division of Intramural Research, NIAID, NIH.http://www.virologyj.comam2023Medical Virolog

    Evaluation of the HIV-1 polymerase gene sequence diversity for prediction of recent HIV-1 infections using Shannon entropy analysis

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    SUPPLEMENTARY MATERIALS : TABLE S1: List of articles from which HIV-1 subtype C reference sequences were obtained; Supplementary TABLE S2: Nucleotide differences within amino acid mutations found to have a different distribution between recent and chronic infection sequences; FIGURE S1: Amino acid sequence alignment to show the difference in sequences between recent and chronic HIV-1 infection; FIGURE S2: Comparison of differences in amino acids E628 and R629 in study sequences and non-subtype C reference sequences, for recent and chronic sequences.DATA AVAILABILITY STATEMENT : All data generated or analysed during this study are included in this manuscript and its supplementary information files.HIV-1 incidence is an important parameter for assessing the impact of HIV-1 interventions. The aim of this study was to evaluate HIV-1 polymerase (pol) gene sequence diversity for the prediction of recent HIV-1 infections. Complete pol Sanger sequences obtained from 45 participants confirmed to have recent or chronic HIV-1 infection were used. Shannon entropy was calculated for amino acid (aa) sequences for the entire pol and for sliding windows consisting of 50 aa each. Entropy scores for the complete HIV-1 pol were significantly higher in chronic compared to recent HIV-1 infections (p < 0.0001) and the same pattern was observed for some sliding windows (p-values ranging from 0.011 to <0.001), leading to the identification of some aa mutations that could discriminate between recent and chronic infection. Different aa mutation groups were assessed for predicting recent infection and their performance ranged from 64.3% to 100% but had a high false recency rate (FRR), which was decreased to 19.4% when another amino acid mutation (M456) was included in the analysis. The pol-based molecular method identified in this study would not be ideal for use on its own due to high FRR; however, this method could be considered for complementing existing serological assays to further reduce FRR.The National Research Foundation (NRF), Poliomyelitis Research Foundation, Discovery Foundation, National Health Laboratory Service Research Trust (NHLS-RT), South African Medical Research Council Self-Initiated Research (MRC-SIR), University of Pretoria Faculty of Health Sciences Research Committee, the South African Research Chairs Initiative of the Department of Science and Innovation and National Research Foundation of South Africa and the Division of Intramural Research.https://www.mdpi.com/journal/virusesam2023Medical Virolog

    Use of injectable hormonal contraception and women’s risk of herpes simplex virus type 2 acquisition: a prospective study of couples in Rakai, Uganda

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    Background The injectable hormonal contraceptive depo-medroxyprogesterone acetate (DMPA) has been associated with increased risk of HIV acquisition, but fi ndings are inconsistent. Whether DMPA increases the risk of other sexually transmitted viral infections is unknown. We assessed the association between DMPA use and incident herpes simplex virus type 2 (HSV2) infection in women. Methods In this prospective study, we enrolled HIV-negative and HSV2-negative women aged 15–49 years whose HIV-negative male partners were concurrently enrolled in a randomised trial of male circumcision in Rakai, Uganda. We excluded women if either they or their male partners HIV seroconverted. The primary outcome was HSV2 seroconversion, assessed annually. The male circumcision trial was registered with ClinicalTrials.gov, number NCT00425984. Findings Between Aug 11, 2003, and July 6, 2006, we enrolled 682 women in this study. We noted HSV2 seroconversions in 70 (10%) women. Incidence was 13·5 per 100 person-years in women consistently using DMPA (nine incident infections per 66·5 person-years), 4·3 per 100 person-years in pregnant women who were not using hormonal contraception (18 incident infections per 423·5 person-years), and 6·6 per 100 person-years in women who were neither pregnant nor using hormonal contraception (35 incident infections per 529·5 person-years). Women consistently using DMPA had an adjusted hazard ratio for HSV2 seroconversion of 2·26 (95% CI 1·09–4·69; p=0·029) compared with women who were neither pregnant nor using hormonal contraception. Of 132 women with HSV2-seropositive partners, seroconversion was 36·4 per 100 person-years in consistent DMPA users (four incident infections per 11 person-years) and 10·7 per 100 person-years in women who were neither pregnant nor using hormonal contraception (11 incident infections per 103 person-years; adjusted hazard ratio 6·23, 95% CI 1·49–26·3; p=0·012). Interpretation Consistent DMPA use might increase risk of HSV2 seroconversion; however, study power was low. These fi ndings should be assessed in larger populations with more frequent follow-up than in this study, and other contraceptive methods should also be assessed. Access to a wide range of highly eff ective contraceptive methods is needed for women, particularly in sub-Saharan Africa

    Addressing an HIV cure in LMIC

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    HIV-1 persists in infected individuals despite years of antiretroviral therapy (ART), due to the formation of a stable and long-lived latent viral reservoir. Early ART can reduce the latent reservoir and is associated with post-treatment control in people living with HIV (PLWH). However, even in post-treatment controllers, ART cessation after a period of time inevitably results in rebound of plasma viraemia, thus lifelong treatment for viral suppression is indicated. Due to the difficulties of sustained life-long treatment in the millions of PLWH worldwide, a cure is undeniably necessary. This requires an in-depth understanding of reservoir formation and dynamics. Differences exist in treatment guidelines and accessibility to treatment as well as social stigma between low- and-middle income countries (LMICs) and high-income countries. In addition, demographic differences exist in PLWH from different geographical regions such as infecting viral subtype and host genetics, which can contribute to differences in the viral reservoir between different populations. Here, we review topics relevant to HIV-1 cure research in LMICs, with a focus on sub-Saharan Africa, the region of the world bearing the greatest burden of HIV-1. We present a summary of ART in LMICs, highlighting challenges that may be experienced in implementing a HIV-1 cure therapeutic. Furthermore, we discuss current research on the HIV-1 latent reservoir in different populations, highlighting research in LMIC and gaps in the research that may facilitate a global cure. Finally, we discuss current experimental cure strategies in the context of their potential application in LMICs

    Antibody attributes that predict the neutralization and effector function of polyclonal responses to SARS-CoV-2

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    BACKGROUND: While antibodies can provide significant protection from SARS-CoV-2 infection and disease sequelae, the specific attributes of the humoral response that contribute to immunity are incompletely defined. METHODS: We employ machine learning to relate characteristics of the polyclonal antibody response raised by natural infection to diverse antibody effector functions and neutralization potency with the goal of generating both accurate predictions of each activity based on antibody response profiles as well as insights into antibody mechanisms of action. RESULTS: To this end, antibody-mediated phagocytosis, cytotoxicity, complement deposition, and neutralization were accurately predicted from biophysical antibody profiles in both discovery and validation cohorts. These models identified SARS-CoV-2-specific IgM as a key predictor of neutralization activity whose mechanistic relevance was supported experimentally by depletion. CONCLUSIONS: Validated models of how different aspects of the humoral response relate to antiviral antibody activities suggest desirable attributes to recapitulate by vaccination or other antibody-based interventions

    HIV subtype is not associated with dementia among individuals with moderate and advanced immunosuppression in Kampala, Uganda

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    HIV-associated neurocognitive disorders (HAND) are a common neurological manifestation of HIV infection. A previous study suggested that HIV dementia may be more common among patients with subtype D virus than among those with subtype A virus among HIV+ individuals with advanced immunosuppression. We conducted a study to evaluate the frequency of HIV dementia, and the association of HIV dementia with HIV subtype and compartmentalization among HIV+ individuals with moderate and advanced immunosuppression (CD4 lymphocyte count >150 cells/μL and < 250 cells/μL)

    Characterization of the Neutralizing Antibody Response in a Case of Genetically Linked HIV Superinfection.

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    This report describes the identification of a genetically confirmed linked heterosexual human immunodeficiency virus (HIV) superinfection (HIV-SI) in a woman with chronic HIV infection who acquired a second strain of the virus from her husband. Serum neutralizing antibody (NAb) responses against their homologous and heterologous viruses, including the superinfecting strain, in the woman and her husband were examined before and after onset of HIV-SI. The woman displayed a moderately potent and broad anti-HIV NAb response prior to superinfection but did not possess NAb activity against the superinfecting strain. This case highlights the unique potential of linked HIV-SI studies to examine natural protection from HIV infection

    Treatment as Prevention: Characterization of Partner Infections in the HIV Prevention Trials Network 052 Trial

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    HIV Prevention Trials Network (HPTN) 052 demonstrated that antiretroviral therapy (ART) prevents HIV transmission in serodiscordant couples. HIV from index-partner pairs was analyzed to determine the genetic linkage status of partner infections. Forty-six infections were classified as linked, indicating that the index was the likely source of the partner’s infection. Lack of viral suppression and higher index viral load were associated with linked infection. Eight linked infections were diagnosed after the index started ART: four near the time of ART initiation and four after ART failure. Linked infections were not observed when the index participant was stably suppressed on ART
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