Detection of antibody-dependent complement mediated inactivation of both autologous and heterologous virus in primary HIV-1 infection

Specific CD8 T-cell responses to human immunodeficiency virus type 1 (HIV-1) are induced in primary infection and make an important contribution to the control of early viral replication. The importance of neutralizing antibodies in containing primary viremia is questioned because they usually arise much later. Nevertheless antienvelope antibodies develop simultaneously with, or even before, peak viremia. We determined whether such antibodies might control viremia by complement-mediated inactivation (CMI). In each of seven patients studied, antibodies capable of CMI appeared at or shortly after the peak in viremia, concomitantly with detection of virus-specific T-cell responses. The CMI was effective on both autologous and heterologous HIV-1 isolates. Activation of the classical pathway and direct viral lysis were at least partly responsible. Since immunoglobulin G (IgG)-antibodies triggered the CMI, specific memory B cells could also be induced by vaccination. Thus, consideration should be given to vaccination strategies that induce IgG antibodies capable of CMI

Understanding the reactogenicity of 4CMenB vaccine: Comparison of a novel and conventional method of assessing post-immunisation fever and correlation with pre-release in vitro pyrogen testing

BACKGROUND: Better understanding of vaccine reactogenicity is crucial given its potential impact upon vaccine safety and acceptance. Here we report a comparison between conventional and novel (continuous) methods of monitoring temperature and evaluate any association between reactogenicity and the monocyte activation test (MAT) employed for testing four-component capsular group B meningococcal vaccine (4CMenB) batches prior to release for clinical use in Europe. METHODS: Healthy 7-12-week-old infants were randomised in two groups: group PCV13 2 + 1 (received pneumococcal conjugate vaccine 13 valent (PCV13) at 2, 4 and 12 months) and group PCV13 1 + 1 (received reduced schedule at 3 and 12 months). In both, infants received the remaining immunisations as per UK national schedule (including 4CMenB at 2, 4 and 12 months of age). Fever was measured for the first 24 h after immunisations using an axillary thermometer and with a wireless continuous temperature monitoring device (iButton®). To measure the relative pyrogenicity of individual 4CMenB batches, MAT was performed according to Ph. Eu. chapter 2.6.30 method C using PBMCs with IL-6 readout. RESULTS: Fever rates detected by the iButton® ranged from 28.7% to 76.5% and from 46.6% to 71.1% in group PCV13 2 + 1 and PCV13 1 + 1 respectively, across all study visits. The iButton® recorded a higher number of fever episodes when compared with axillary measurements in both groups (range of axillary temperature fevers; group PCV13 2 + 1: 6.7%-38%; group PCV13 1 + 1: 11.4%-37.1%). An agreement between the two methods was between 0.39 and 0.36 (p < 0.001) at 8 h' time-point post primary immunisations. No correlation was found between MAT scores and fever rates, or other reported adverse events. CONCLUSIONS: It is likely that conventional, intermittent, fever measurements underestimates fever rates following immunisation. 4CMenB MAT scores didn't predict reactogenicity, providing reassurance that vaccine batches with the highest acceptable pyrogen level are not associated with an increase in adverse events. Clinicaltrials.gov identifier: NCT02482636

Geographically widespread invasive meningococcal disease caused by a ciprofloxacin resistant non-groupable strain of the ST-175 clonal complex.

INTRODUCTION: Invasive meningococcal disease (IMD) caused by non-serogroupable (NG) strains mainly affects immunocompromised individuals. Reduced susceptibility to penicillin in meningococci is increasing in Europe but ciprofloxacin resistance remains rare. In 2019, three travel-related meningococcal disease cases caused by a ciprofloxacin-resistant NG strain were identified in England, leading Germany to report four additional IMD cases (2016 to 2019). We describe these and newly identified cases and characterise the strain responsible. METHODS: Cases were identified as part of national surveillance and by analysing available genomes using PubMLST tools. RESULTS: Of the cases identified in England in 2019, two geographically distinct cases developed conjunctivitis after returning from Mecca (Kingdom of Saudi Arabia) and a third linked case presented with IMD. Of the four cases from Germany, three occurred in asylum seekers - two familial and a further geographically distinct case. Further IMD cases were identified in Italy (n = 2; 2017-2018), Sweden (n = 1; 2016) and England (n = 1; 2015). A single ST-175 clonal complex (cc175) strain with genosubtype P1.22-11,15-25 was responsible. Decreased susceptibility to penicillin was widespread with three ciprofloxacin resistant subclusters. Constituent isolates were potentially covered by subcapsular vaccines. CONCLUSION: This disease associated NG cc175 strain exhibits resistance to antibiotics commonly used to prevent IMD but is potentially covered by subcapsular (meningococcal B) vaccines

The helicase HAGE prevents interferon-a-induced PML expression in ABCB5+ malignant melanoma-initiating cells by promoting the expression of SOCS1

The tumour suppressor PML (promyelocytic leukaemia protein) regulates several cellular pathways involving cell growth, apoptosis, differentiation and senescence. PML also has an important role in the regulation of stem cell proliferation and differentiation. Here, we show the involvement of the helicase HAGE in the transcriptional repression of PML expression in ABCB5 + malignant melanoma-initiating cells (ABCB5 + MMICs), a population of cancer stem cells which are responsible for melanoma growth, progression and resistance to drug-based therapy. HAGE prevents PML gene expression by inhibiting the activation of the JAK-STAT (janus kinase-signal transducers and activators of transcription) pathway in a mechanism which implicates the suppressor of cytokine signalling 1 (SOCS1). Knockdown of HAGE led to a significant decrease in SOCS1 protein expression, activation of the JAK-STAT signalling cascade and a consequent increase of PML expression. To confirm that the reduction in SOCS1 expression was dependent on the HAGE helicase activity, we showed that SOCS1, effectively silenced by small interfering RNA, could be rescued by re-introduction of HAGE into cells lacking HAGE. Furthermore, we provide a mechanism by which HAGE promotes SOCS1 mRNA unwinding and protein expression in vitro

Prevalence of human papillomavirus antibodies in young female subjects in England

Sera from 1483 female subjects in England aged 10–29 years were tested. The age-standardised seroprevalence was 10.7% (95% confidence intervals 9.0–12.3) for human papillomavirus (HPV) 6, 2.7% (1.8–3.6) for HPV 11, 11.9% (10.2–13.6) for HPV 16, 4.7% (3.5–5.8) for HPV 18, and 20.7% (18.6–22.7) for any of the four types

Cytoplasmic PML promotes TGF-β-associated epithelial–mesenchymal transition and invasion in prostate cancer

Epithelial–mesenchymal transition (EMT) is a key event that is involved in the invasion and dissemination of cancer cells. Although typically considered as having tumour-suppressive properties, transforming growth factor (TGF)-β signalling is altered during cancer and has been associated with the invasion of cancer cells and metastasis. In this study, we report a previously unknown role for the cytoplasmic promyelocytic leukaemia (cPML) tumour suppressor in TGF-β signalling-induced regulation of prostate cancer-associated EMT and invasion. We demonstrate that cPML promotes a mesenchymal phenotype and increases the invasiveness of prostate cancer cells. This event is associated with activation of TGF-β canonical signalling pathway through the induction of Sma and Mad related family 2 and 3 (SMAD2 and SMAD3) phosphorylation. Furthermore, the cytoplasmic localization of promyelocytic leukaemia (PML) is mediated by its nuclear export in a chromosomal maintenance 1 (CRM1)-dependent manner. This was clinically tested in prostate cancer tissue and shown that cytoplasmic PML and CRM1 co-expression correlates with reduced disease-specific survival. In summary, we provide evidence of dysfunctional TGF-β signalling occurring at an early stage in prostate cancer. We show that this disease pathway is mediated by cPML and CRM1 and results in a more aggressive cancer cell phenotype. We propose that the targeting of this pathway could be therapeutically exploited for clinical benefit

Serological surveillance of influenza in an English sentinel network: pilot study protocol.

BACKGROUND: Rapidly undertaken age-stratified serology studies can produce valuable data about a new emerging infection including background population immunity and seroincidence during an influenza pandemic. Traditionally seroepidemiology studies have used surplus laboratory sera with little or no clinical information or have been expensive detailed population based studies. We propose collecting population based sera from the Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC), a sentinel network with extensive clinical data. AIM: To pilot a mechanism to undertake population based surveys that collect serological specimens and associated patient data to measure seropositivity and seroincidence due to seasonal influenza, and create a population based serology bank. METHODS AND ANALYSIS: Setting and Participants: We will recruit 6 RCGP RSC practices already taking nasopharyngeal virology swabs. Patients who attend a scheduled blood test will be consented to donate additional blood samples. Approximately 100-150 blood samples will be collected from each of the following age bands - 18- 29, 30- 39, 40- 49, 50- 59, 60- 69 and 70+ years. METHODS: We will send the samples to the Public Health England (PHE) Seroepidemiology Unit for processing and storage. These samples will be tested for influenza antibodies, using haemagglutination inhibition assays. Serology results will be pseudonymised, sent to the RCGP RSC and combined using existing processes at the RCGP RSC secure hub. The influenza seroprevalence results from the RCGP cohort will be compared against those from the annual PHE influenza residual serosurvey. ETHICS AND DISSEMINATION: Ethical approval was granted by the Proportionate Review Sub- Committee of the London - Camden & Kings Cross on 6 February 2018. This study received approval from Health Research Authority on 7 February 2018. On completion the results will be made available via peer-reviewed journals

Professor Mark Wainberg

When Kuan-Teh Jeang (‘Teh’ to everyone) made the bold and prescient decision to join the earliest wave of pure online academic publishing and founded the journal Retrovirology, Mark Wainberg was one of the simplest and most obvious choices for him to invite to join the editorial team. Mark’s long established and highly respected position in the field of HIV and AIDS research added enormously to the embryonic journal’s immediate credibility and stature. Mark’s seminal achievements in recent years have been in antiretroviral therapy and viral resistance mechanisms but, in a publishing career on HIV spanning 30 years and over 550 publications, there were few areas of HIV research that he did not investigate and he brought that enormous range of expertise and experience to Retrovirology. His many achievements in the field will be described in detail by others, including his trainees and colleagues from Canada, in a shortly to be published obituary in this journal. When Teh himself was so sadly taken from us it was again Mark’s stature and reputation and his boundless enthusiasm and energy that was so important in maintaining the momentum and profile of the Journal as he took on the role of Co-Editor in Chief

Extreme genetic fragility of the HIV-1 capsid

Genetic robustness, or fragility, is defined as the ability, or lack thereof, of a biological entity to maintain function in the face of mutations. Viruses that replicate via RNA intermediates exhibit high mutation rates, and robustness should be particularly advantageous to them. The capsid (CA) domain of the HIV-1 Gag protein is under strong pressure to conserve functional roles in viral assembly, maturation, uncoating, and nuclear import. However, CA is also under strong immunological pressure to diversify. Therefore, it would be particularly advantageous for CA to evolve genetic robustness. To measure the genetic robustness of HIV-1 CA, we generated a library of single amino acid substitution mutants, encompassing almost half the residues in CA. Strikingly, we found HIV-1 CA to be the most genetically fragile protein that has been analyzed using such an approach, with 70% of mutations yielding replication-defective viruses. Although CA participates in several steps in HIV-1 replication, analysis of conditionally (temperature sensitive) and constitutively non-viable mutants revealed that the biological basis for its genetic fragility was primarily the need to coordinate the accurate and efficient assembly of mature virions. All mutations that exist in naturally occurring HIV-1 subtype B populations at a frequency &gt;3%, and were also present in the mutant library, had fitness levels that were &gt;40% of WT. However, a substantial fraction of mutations with high fitness did not occur in natural populations, suggesting another form of selection pressure limiting variation in vivo. Additionally, known protective CTL epitopes occurred preferentially in domains of the HIV-1 CA that were even more genetically fragile than HIV-1 CA as a whole. The extreme genetic fragility of HIV-1 CA may be one reason why cell-mediated immune responses to Gag correlate with better prognosis in HIV-1 infection, and suggests that CA is a good target for therapy and vaccination strategies