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Distinguishing HIV latency and HIV persistence More than 20 years after the discovery of combination antiretroviral therapy (ART), complete eradication of HIV infection has not yet been achieved, with the [...], Although antiretroviral therapies (ARTs) potently inhibit HIV replication, they do not eradicate the virus. HIV persists in cellular and anatomical reservoirs that show minimal decay during ART. A large number of studies conducted during the past 20 years have shown that HIV persists in a small pool of cells harboring integrated and replication-competent viral genomes. The majority of these cells do not produce viral particles and constitute what is referred to as the latent reservoir of HIV infection. Therefore, although HIV is not considered as a typical latent virus, it can establish a state of nonproductive infection under rare circumstances, particularly in memory [CD4.sup.+] T cells, which represent the main barrier to HIV eradication. While it was originally thought that the pool of latently infected cells was largely composed of cells harboring transcriptionally silent genomes, recent evidence indicates that several blocks contribute to the nonproductive state of these cells. Here, we describe the virological and immunological factors that play a role in the establishment and persistence of the pool of latently infected cells and review the current approaches aimed at eliminating the latent HIV reservoir.

The experiences of nurses who blew the whistle during the COVID‐19 pandemic have exposed gaps and revealed an urgent need to revisit our understanding of whistleblowing. Aim: The aim was to develop a better understanding of whistleblowing during a pandemic by using the experiences and lessons learned of Quebec nurses who blew the whistle during the first wave of COVID‐19 as a case study. More specifically, to explore why and how nurses blew the whistle, what types of wrongdoing triggered their decision to do so and how context shaped the whistleblowing process as well as its consequences (including perceived consequences). Design: The study followed a single‐case study design with three embedded units of analysis. Methods: We used content analysis to analyse 83 news stories and 597 forms posted on a whistleblowing online platform. We also conducted 15 semi‐structured interviews with nurses and analysed this data using a thematic analysis approach. Finally, we triangulated the findings. Results: We identified five themes across the case study. (1) During the first wave of COVID‐19, Quebec nurses experienced a shifting sense of loyalty and relationship to workplace culture. (2) They witnessed exceedingly high numbers of intersecting wrongdoings amplified by mismanagement and long‐standing issues. (3) They reported a lack of trust and transparency; thus, a need for external whistleblowing. (4) They used whistleblowing to reclaim their rights (notably, the right to speak) and build collective solidarity. (5) Finally, they saw whistleblowing as an act of moral courage in the face of a system in crisis. Together, these themes elucidate why and how nurse whistleblowing is different in pandemic times. Conclusion: Our findings offer a more nuanced understanding of nurse whistleblowing and address important gaps in knowledge. They also highlight the need to rethink external whistleblowing, develop whistleblowing tools and advocate for whistleblowing protection. Impact In many ways, the COVID‐19 pandemic has challenged our foundational understanding of whistleblowing and, as a result, it has limited the usefulness of existing literature on the topic for reasons that will be brought to light in this paper. We believe that studying the uniqueness of whistleblowing during a pandemic can address this gap by describing why and how health care workers blow the whistle during a pandemic and situating this experience within a broader social, political, organizational context. [ABSTRACT FROM AUTHOR]

Whistleblowing about critical issues by care staff is an essential component of any well-functioning health care system. During a pandemic, rapid communication of critical information is essential to identify and solve problems. In times of crisis, however, this kind of communication is difficult. In the province of Quebec, Canada, testimonies from nurses, licensed practical nurses (LPNs), and other health professionals during the COVID-19 pandemic indicate that the province's health care settings have met whistleblowers' concerns with insufficient corrective measures and, in some cases, retaliation against whistleblowers themselves. This crisis led a union to create an online platform to collect testimonials from the public and quickly make them available to the public and the media. By presenting a content analysis of testimonials submitted by nurses and LPNs, this article aims, on one hand, to identify the issues raised and, on the other, to examine the role and usefulness of this kind of platform for nurses who engage in acts of whistleblowing. [ABSTRACT FROM AUTHOR]

The phenotypic characterization of the cells in which HIV persists during antiretroviral therapy (ART) remains technically challenging. We developed a simple flow cytometry-based assay to quantify and characterize infected cells producing HIV proteins during untreated and treated HIV infection. By combining two antibodies targeting the HIV capsid in a standard intracellular staining protocol, we demonstrate that p24-producing cells can be detected with high specificity and sensitivity in the blood from people living with HIV. In untreated individuals, the frequency of productively infected cells strongly correlated with plasma viral load. Infected cells preferentially displayed a transitional memory phenotype and were enriched in Th17, peripheral Tfh and regulatory T cells subsets. These cells also preferentially expressed activation markers (CD25, HLA-DR, Ki67), immune checkpoint molecules (PD-1, LAG-3, TIGIT, Tim-3) as well as the integrins α4β7 and α4β1. In virally suppressed individuals on ART, p24-producing cells were only detected upon stimulation (median frequency of 4.3 p24+ cells/106 cells). These measures correlated with other assays assessing the size of the persistent reservoir including total and integrated HIV DNA, Tat/rev Induced Limiting Dilution Assay (TILDA) and quantitative viral outgrowth assay (QVOA). In ART-suppressed individuals, p24-producing cells preferentially displayed a transitional and effector memory phenotype, and expressed immune checkpoint molecules (PD-1, TIGIT) as well as the integrin α4β1. Remarkably, α4β1 was expressed by more than 70% of infected cells both in untreated and ART-suppressed individuals. Altogether, these results highlight a broad diversity in the phenotypes of HIV-infected cells in treated and untreated infection and suggest that strategies targeting multiple and phenotypically distinct cellular reservoirs will be needed to exert a significant impact on the size of the reservoir. [ABSTRACT FROM AUTHOR]

Elite controllers (ECs) are a rare subset of HIV-1 slow progressors characterized by prolonged viremia suppression. HLA alleles B27 and B57 promote the cytotoxic T lymphocyte (CTL)-mediated depletion of infected cells in ECs, leading to the emergence of escape mutations in the viral capsid (CA). Whether those mutations modulate CA detection by innate sensors and effectors is poorly known. Here, we investigated the targeting of CA from B27/B57+ individuals by cytosolic antiviral factors Mx2 and TRIM5α. Toward that aim, we constructed chimeric HIV-1 vectors using CA isolated from B27/B57+ or control subjects. HIV-1 vectors containing B27/B57+-specific CA had increased sensitivity to TRIM5α but not to Mx2. Following exposure to those vectors, cells showed increased resistance against both TRIM5α-sensitive and -insensitive HIV-1 strains. Induction of the antiviral state did not require productive infection by the TRIM5α-sensitive virus, as shown using chemically inactivated virions. Depletion experiments revealed that TAK1 and Ubc13 were essential to the TRIM5α-dependent antiviral state. Accordingly, induction of the antiviral state was accompanied by the activation of NF-κB and AP-1 in THP-1 cells. Secretion of IFN-I was involved in the antiviral state in THP-1 cells, as shown using a receptor blocking antibody. This work identifies innate activation pathways that are likely to play a role in the natural resistance to HIV-1 progression in ECs. [ABSTRACT FROM AUTHOR]

The type I interferon (IFN-I)-inducible human restriction factor TRIM5α inhibits the infection of human cells by specific nonhuman retroviruses, such as N-MLV and EIAV, but does not generally target HIV-1. However, the introduction of two aminoacid substitutions, R332G and R355G, in the human TRIM5α (huTRIM5α) domain responsible for retroviral capsid recognition leads to efficient HIV-1 restriction upon stable over-expression. CRISPR-Cas-based approaches to precisely edit DNA could be employed to modify TRIM5 in human cells. Toward this aim, we used a DNA transfection-based CRISPR-Cas9 genome editing protocol to successfully mutate TRIM5 to its potentially HIV-1-restrictive version by homology-directed repair (HDR) in HEK293T cells. Nine clones bearing at least one HDR-edited TRIM5 allele containing both mutations were isolated (5.6% overall efficiency), whereas another one contained only the R332G mutation. Of concern, several of these HDR-edited clones contained on-target undesired mutations, and none had all the alleles corrected. Our study demonstrates the feasibility of editing the TRIM5 gene in human cells and identifies the main challenges to be addressed in order to use this approach to confer protection from HIV-1. [ABSTRACT FROM AUTHOR]

HIV persists in tissues during antiretroviral therapy (ART), but the relative contribution of different anatomical compartments to the viral reservoir in humans remains unknown. We performed an extensive characterization of HIV reservoirs in two men who donated their bodies to HIV cure research and who had been on suppressive ART for years. HIV DNA is detected in all tissues, with large variations across anatomical compartments and between participants. Intact HIV genomes represent 2% and 25% of all proviruses in the two participants and are mainly detected in secondary lymphoid organs, with the spleen and mediastinal lymph nodes harboring intact viral genomes in both individuals. Multiple copies of identical HIV genomes are found in all tissues, indicating that clonal expansions are common in anatomical sites. The majority (>85%) of these expanded clones are shared across multiple tissues. These findings suggest that infected cells expand, migrate, and possibly circulate between anatomical sites. [Display omitted] • In people on ART, half the HIV genomes in tissues are clonally expanded • Genetically intact HIV proviruses are more often found in lymphoid tissues • Identical proviral sequences are frequently found in distant tissues Dufour et al. study viral reservoirs by analyzing multiple samples from two men who donated their bodies for HIV cure research. They show that genetically intact proviruses are more often found in lymphoid organs. Moreover, half of the HIV genomes in tissues are clonally expanded and are frequently located in distant compartments. [ABSTRACT FROM AUTHOR]

What role do universities play in the early institutional development of public administration education? While related literature aptly describes the role of external influences and demands, universities' influence remains largely unexplored. Using the theory of fields, this article analyzes the role universities of the province of Québec, Canada, had in the early institutional development of public administration education during the 1960s and 1970s. The article shows universities had an impact through academic structures, their positions in different fields of activities, and the profiles of their faculty members. The conclusions of the article are a first step toward an understanding of what universities can do, rather than what they should do, when it comes to educating public servants. [ABSTRACT FROM PUBLISHER]

The article discusses various reports published within the issue, including one by Ernie Lightman, Dean Herd, and Andrew Mitchell on the analysis of the relationship of the labor force's welfare and the actual workfare state, one by Katherine Krull on the beneficial change in policy orientation from pro-natalism of pro-familism in Quebec, and one by Dennis Raphael on the association of health and distribution of income.

The article focuses on the significance of considering new public management (NPM) as paradigm. It talks about Thomas Kuhn's theory of paradigms, which includes law, theory, application and instrumentation, and its use for the social sciences. Three levels of paradigms in Kuhn's theory that were identified by two commentaries include metaphysical or epistemological, sociological, and exemplars or artefacts. The paradigms in social and applied sciences and their application to the new public management are discussed.

Tripartite-motif-containing protein 5 isoform α (TRIM5α) is a cytoplasmic antiretroviral effector upregulated by type I interferons (IFN-I). We previously showed that two points mutations, R332G/R335G, in the retroviral capsid-binding region confer human TRIM5α the capacity to target and strongly restrict HIV-1 upon overexpression of the mutated protein. Here, we used clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9-mediated homology-directed repair (HDR) to introduce these two mutations in the endogenous human TRIM5 gene. We found 6 out of 47 isolated cell clones containing at least one HDR-edited allele. One clone (clone 6) had both alleles containing R332G, but only one of the two alleles containing R335G. Upon challenge with an HIV-1 vector, clone 6 was significantly less permissive compared to unmodified cells, whereas the cell clones with monoallelic modifications were only slightly less permissive. Following interferon (IFN)-β treatment, inhibition of HIV-1 infection in clone 6 was significantly enhanced (~40-fold inhibition). TRIM5α knockdown confirmed that HIV-1 was inhibited by the edited TRIM5 gene products. Quantification of HIV-1 reverse transcription products showed that inhibition occurred through the expected mechanism. In conclusion, we demonstrate the feasibility of potently inhibiting a viral infection through the editing of innate effector genes. Our results also emphasize the importance of biallelic modification in order to reach significant levels of inhibition by TRIM5α. [ABSTRACT FROM AUTHOR]

The PML (promyelocytic leukemia) protein is a member of the TRIM family, a large group of proteins that show high diversity in functions but possess a common tripartite motif giving the family its name. We and others recently reported that both murine PML (mPML) and human PML (hPML) strongly restrict the early stages of infection by HIV-1 and other lentiviruses when expressed in mouse embryonic fibroblasts (MEFs). This restriction activity was found to contribute to the type I interferon (IFN-I)-mediated inhibition of HIV-1 in MEFs. Additionally, PML caused transcriptional repression of the HIV-1 promoter in MEFs. In contrast, the modulation of the early stages of HIV-1 infection of human cells by PML has been investigated by RNA interference, with unclear results. In order to conclusively determine whether PML restricts HIV-1 or not in human cells, we used the clustered regularly interspaced short palindromic repeat with Cas9 (CRISPR-Cas9) system to knock out its gene in epithelial, lymphoid, and monocytic human cell lines. Infection challenges showed that PML knockout had no effect on the permissiveness of these cells to HIV-1 infection. IFN-I treatments inhibited HIV-1 equally whether PML was expressed or not. Overexpression of individual hPML isoforms, or of mPML, in a human T cell line did not restrict HIV-1. The presence of PML was not required for the restriction of nonhuman retroviruses by TRIM5α (another human TRIM protein), and TRIM5α was inhibited by arsenic trioxide through a PML-independent mechanism. We conclude that PML is not a restriction factor for HIV-1 in human cell lines representing diverse lineages. IMPORTANCE PML is involved in innate immune mechanisms against both DNA and RNA viruses. Although the mechanism by which PML inhibits highly divergent viruses is unclear, it was recently found that it can increase the transcription of interferon-stimulated genes (ISGs). However, whether human PML inhibits HIV-1 has been debated. Here we provide unambiguous, knockout-based evidence that PML does not restrict the early postentry stages of HIV-1 infection in a variety of human cell types and does not participate in the inhibition of HIV-1 by IFN-I. Although this study does not exclude the possibility of other mechanisms by which PML may interfere with HIV-1, we nonetheless demonstrate that PML does not generally act as an HIV-1 restriction factor in human cells and that its presence is not required for IFN-I to stimulate the expression of anti-HIV-1 genes. These results contribute to uncovering the landscape of HIV-1 inhibition by ISGs in human cells.

IFN-induced restriction factors can significantly affect the replicative capacity of retroviruses in mammals. TRIM5α (tripartite motif protein 5, isoform α) is a restriction factor that acts at early stages of the virus life cycle by intercepting and destabilizing incoming retroviral cores. Sensitivity to TRIM5α maps to the N-terminal domain of the retroviral capsid proteins. In several New World and Old World monkey species, independent events of retrotransposon-mediated insertion of the cyclophilin A (CypA)-coding sequence in the trim5 gene have given rise to TRIMCyp (also called TRIM5-CypA), a hybrid protein that is active against some lentiviruses in a species-specific fashion. In particular, TRIMCyp from the owl monkey (omkTRIMCyp) very efficiently inhibits human immunodeficiency virus type 1 (HIV-1). Previously, we showed that disrupting the integrity of microtubules (MTs) and of cytoplasmic dynein complexes partially rescued replication of retroviruses, including HIV-1, from restriction mediated by TRIM5α. Here, we showed that efficient restriction of HIV-1 by omkTRIMCyp was similarly dependent on the MT network and on dynein complexes, but in a context-dependent fashion. When omkTRIMCyp was expressed in human HeLa cells, restriction was partially counteracted by pharmacological agents targeting MTs or by small interfering RNA-mediated inhibition of dynein. The same drugs (nocodazole and paclitaxel) also rescued HIV-1 from restriction in cat CRFK cells, although to a lesser extent. Strikingly, neither nocodazole, paclitaxel nor depletion of the dynein heavy chain had a significant effect on the restriction of HIV-1 in an owl monkey cell line. These results suggested the existence of cell-specific functional interactions between MTs/dynein and TRIMCyp., (© 2015 The Authors.)