HIV transcription persists in the brain of virally suppressed people with HIV.

HIV persistence in the brain is a barrier to cure, and potentially contributes to HIV-associated neurocognitive disorders. Whether HIV transcription persists in the brain despite viral suppression with antiretroviral therapy (ART) and is subject to the same blocks to transcription seen in other tissues and blood, is unclear. Here, we quantified the level of HIV transcripts in frontal cortex tissue from virally suppressed or non-virally suppressed people with HIV (PWH).

Nanocapsules Comprised of Purified Protein: Construction and Applications in Vaccine Research.

Nanoparticles show great promise as a platform for developing vaccines for the prevention of infectious disease. We have been investigating a method whereby nanocapsules can be formulated from protein, such that the final capsules contain only the cross-linked protein itself. Such nanocapsules are made using a silica templating system and can be customised in terms of size and porosity.

Regional Analysis of Intact and Defective HIV Proviruses in the Brain of Viremic and Virally Suppressed People with HIV.

Here, we provide the first regional analysis of intact and defective HIV reservoirs within the brain. Brain tissue from both viremic and virally suppressed people with HIV (PWH) harbored HIV pol DNA in all regions tested, with lower levels present in basal ganglia and cerebellum relative to frontal white matter. Intact proviruses were primarily found in the frontal white matter but also detected in other brain regions of PWH, demonstrating frontal white matter as a major brain reservoir of intact, potentially replication competent HIV DNA that persists despite antiretroviral therapy.

Persistence of envelopes in different CD4+ T-cell subsets in antiretroviral therapy-suppressed people with HIV.

Objectives: Despite suppressive antiretroviral therapy (ART), HIV can persist in a diverse range of CD4+ T-cell subsets. Through longitudinal env sampling from people with HIV (PWH) on ART, we characterized the persistence and phenotypic properties of HIV envs over two time-points (T1 and T2).

Methods: Longitudinal blood and lymphoid tissue samples were obtained from eight PWH on suppressive ART.

DExD/H-box helicases in HIV-1 replication and their inhibition.

Antiretroviral therapy (ART) reduces human immunodeficiency virus type 1 (HIV-1) infection, but selection of treatment-refractory variants remains a major challenge. HIV-1 encodes 16 canonical proteins, a small number of which are the singular targets of nearly all antiretrovirals developed to date. Cellular factors are increasingly being explored, which may present more therapeutic targets, more effectively target certain aspects of the viral replication cycle, and/or limit viral escape.

Intact HIV Proviruses Persist in the Brain Despite Viral Suppression with ART.

Objective: Human immunodeficiency virus (HIV) persistence in blood and tissue reservoirs, including the brain, is a major barrier to HIV cure and possible cause of comorbid disease. However, the size and replication competent nature of the central nervous system (CNS) reservoir is unclear. Here, we used the intact proviral DNA assay (IPDA) to provide the first quantitative assessment of the intact and defective HIV reservoir in the brain of people with HIV (PWH).

Modular Lentiviral Vectors for Highly Efficient Transgene Expression in Resting Immune Cells.

Gene/cell therapies are promising strategies for the many presently incurable diseases. A key step in this process is the efficient delivery of genes and gene-editing enzymes to many cell types that may be resistant to lentiviral vector transduction. Herein we describe tuning of a lentiviral gene therapy platform to focus on genetic modifications of resting CD4 T cells.

Potential Impact of Human Cytomegalovirus Infection on Immunity to Ovarian Tumours and Cancer Progression.

Ovarian cancer (OC) is one of the most common, and life-threatening gynaecological cancer affecting females. Almost 75% of all OC cases are diagnosed at late stages, where the 5-year survival rate is less than 30%. The aetiology of the disease is still unclear, and there are currently no screening method nor effective treatment strategies for the advanced disease.

Longitudinal analysis of subtype C envelope tropism for memory CD4 T cell subsets over the first 3 years of untreated HIV-1 infection.

Background: HIV-1 infects a wide range of CD4 T cells with different phenotypic properties and differing expression levels of entry coreceptors. We sought to determine the viral tropism of subtype C (C-HIV) Envelope (Env) clones for different CD4 T cell subsets and whether tropism changes during acute to chronic disease progression. HIV-1 envs were amplified from the plasma of five C-HIV infected women from three untreated time points; less than 2 months, 1-year and 3-years post-infection.

Understanding the mechanisms driving the spread of subtype C HIV-1.

Human immunodeficiency virus type 1 (HIV-1) subtype C (C-HIV) is the most prevalent form of HIV-1 globally, accounting for approximately 50% of infections worldwide. C-HIV is the predominant and near-exclusive subtype in the low resource regions of India and Southern Africa. Given the vast diversity of HIV-1 subtypes, it is curious as to why C-HIV constitutes such a large proportion of global infections.

CXCR4-Using HIV Strains Predominate in Naive and Central Memory CD4 T Cells in People Living with HIV on Antiretroviral Therapy: Implications for How Latency Is Established and Maintained.

HIV can persist in people living with HIV (PLWH) on antiretroviral therapy (ART) in multiple CD4 T cell subsets, including naive cells, central memory (CM) cells, transitional (TM) cells, and effector memory (EM) cells. Since these cells express different levels of the viral coreceptors CXCR4 and CCR5 on their surface, we sought to determine whether the HIV envelope protein (Env) was genotypically and phenotypically different between CD4 T cell subsets isolated from PLWH on suppressive ART ( = 8). Single genome amplification for the HIV gene was performed on genomic DNA extracts from different CD4 T cell subsets.

Flow Cytometry Analysis to Identify Human CD4 T Cell Subsets.

Flow cytometry is a powerful tool, which uses lasers to analyze a wide range of different characteristics of cells. It is commonly used to determine the expression of cell surface markers and intracellular molecules to define cells into different populations using cell size, granularity, and fluorescently labeled antibodies. Thus, flow cytometry enables simultaneous and mutliparameter analysis of single cells.

Flow Cytometry Analysis to Identify Human CD8 T Cells.

Flow cytometry is a powerful technique allowing multiparameter detection and quantification of single cells or particles including cell size, granularity, cell components (DNA, mRNA), surface receptors, intracellular proteins, and signaling events. The flow cytometer operates via three main systems: the fluidics, optics, and electronics, which work together to analyze the physical and chemical properties of your sample. The first system, the fluidics, transports your sample in a single stream through the instrument, from the sample tube, pass the lasers, and is either sorted for further experiments or discarded into the waste vessel.

RNASeq Analysis of Mosquito Midguts after Chikungunya Virus Infection.

Chikungunya virus (CHIKV) is an emerging pathogen around the world and causes significant morbidity in patients. A single amino acid mutation in the envelope protein of CHIKV has led to a shift in vector preference towards . While mosquitoes are known to mount an antiviral immune response post-infection, molecular interactions during the course of infection at the tissue level remain largely uncharacterised.

Low levels of HIV-1 envelope-mediated fusion are associated with long-term survival of an infected CCR5-/- patient.

Objectives: This study investigated whether Env-mediated fusion levels of R5X4 viruses are associated with long-term survival of an infected CCR5-/- patient.

Design: Four R5X4 Envs were cloned from each of two infected homosexual individuals (DR and C2) homozygous for the CCR5Δ32 allele. DR is a long-term survivor chronically infected with HIV-1 and his Envs were cloned 12 years after testing HIV-infected, whereas C2 Envs were isolated 1 year after primary infection.

Analysis and dissociation of anti-HIV effects of shRNA to CCR5 and the fusion inhibitor C46.

Background: The gene therapeutic Cal-1 comprises the anti-HIV agents: (i) sh5, a short hairpin RNA to CCR5 that down-regulates CCR5 expression and (ii) maC46 (C46), a peptide that inhibits viral fusion with the cell membrane. These constructs were assessed for inhibition of viral replication and selective cell expansion in a number of settings.

Methods: HIV replication, selective outgrowth and cell surface viral binding were analysed with a single cycle infection assay of six pseudotyped HIV strains and a static and longitudinal passaging of MOLT4/CCR5 cells with HIV.

Analysis of Clinical HIV-1 Strains with Resistance to Maraviroc Reveals Strain-Specific Resistance Mutations, Variable Degrees of Resistance, and Minimal Cross-Resistance to Other CCR5 Antagonists.

Maraviroc (MVC) is an allosteric inhibitor of human immunodeficiency virus type 1 (HIV-1) entry, and is the only CCR5 antagonist licensed for use as an anti-HIV-1 therapeutic. It acts by altering the conformation of the CCR5 extracellular loops, rendering CCR5 unrecognizable by the HIV-1 envelope (Env) glycoproteins. This study aimed to understand the mechanisms underlying the development of MVC resistance in HIV-1-infected patients.

HEALTH TECHNOLOGY ASSESSMENT: THE SCIENTIFIC CAREER OF A POLICY CONCEPT.

Objectives: The aim of this work was to provide a comprehensive overview of the evolution of the health technology assessment (HTA) concept in the scientific literature through a scientometric approach.

Methods: A literature search was conducted, by selecting publications, as well as news from the media, containing "health technology assessment" in their title, abstracts, or keywords. We then undertook a bibliometric and network analysis on the corpus of 2,865 publications thus obtained.

HIV-1 and SIV Predominantly Use CCR5 Expressed on a Precursor Population to Establish Infection in T Follicular Helper Cells.

Background: T follicular helper (Tfh) cells are increasingly recognized as a major reservoir of HIV infection that will likely need to be addressed in approaches to curing HIV. However, Tfh express minimal CCR5, the major coreceptor for HIV-1, and the mechanism by which they are infected is unclear. We have previously shown that macaque Tfh lack CCR5, but are infected with CCR5-using SIV at levels comparable to other memory CD4 T cells.

Frequency and Env determinants of HIV-1 subtype C strains from antiretroviral therapy-naive subjects that display incomplete inhibition by maraviroc.

Background: Entry of human immunodeficiency virus type 1 (HIV-1) into cells involves the interaction of the viral gp120 envelope glycoproteins (Env) with cellular CD4 and a secondary coreceptor, which is typically one of the chemokine receptors CCR5 or CXCR4. CCR5-using (R5) HIV-1 strains that display reduced sensitivity to CCR5 antagonists can use antagonist-bound CCR5 for entry. In this study, we investigated whether naturally occurring gp120 alterations in HIV-1 subtype C (C-HIV) variants exist in antiretroviral therapy (ART)-naïve subjects that may influence their sensitivity to the CCR5 antagonist maraviroc (MVC).

Corrigendum: Detection of a Novel DSPP Mutation by NGS in a Population Isolate in Madagascar.

[This corrects the article on p. 70 in vol. 7, PMID: 26973538.

Genotypic Prediction of Co-receptor Tropism of HIV-1 Subtypes A and C.

Antiretroviral treatment of Human Immunodeficiency Virus type-1 (HIV-1) infections with CCR5-antagonists requires the co-receptor usage prediction of viral strains. Currently available tools are mostly designed based on subtype B strains and thus are in general not applicable to non-B subtypes. However, HIV-1 infections caused by subtype B only account for approximately 11% of infections worldwide.