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£872K awarded to study an exciting new research avenue in lung fibrosis.
Delineating Mpl-dependent and -independent phenotypes of Jak2 V617F- positive MPNs in vivo.
The Jak2 V617F mutation stands as the main driver of myeloproliferative neoplasms (MPNs) by constitutively activating signaling of several type I cytokine receptors, namely those for erythropoietin (EpoR), thrombopoietin (TpoR), and Granulocyte Colony Stimulating Factor (G-CSFR). Among these, TpoR assumes a pivotal role in hematopoietic stem cell renewal and differentiation, being positioned as a key driver of MPNs alongside mutated Jak2. However, the impact of TpoR/MPL absence in the context of Jak2 V617F in vivo has been explored only through a transgenic Jak2 V617F mouse model, where regulation of Jak2 expression does not depend on its natural promoter. In this study, we use a novel mouse model expressing Jak2 V617F under its endogenous promoter at the heterozygous state within a Mpl knock-out background. Our findings indicate that erythrocytosis, leukocytosis and moderate splenomegaly with mild spleen peri-vascular fibrosis persist even in the absence of Mpl expression. Notably, the inherent growth-stimulating effect induced by Jak2 V617F remains consistent across diverse early hematopoietic progenitor populations in the absence of Mpl but is reduced at the stem cell level and does not allow clonal expansion in competitive transplantation. Our results delineate Mpl-dependent and -independent phenotypes induced by Jak2 V617F and confirm that inhibiting Mpl expression at the stem cell level negates the long-term advantage of the mutant clone. Consequently, while MPL emerges as a major player in Jak2 V617F positive MPNs, our study underscores that it is not the exclusive contributor, broadening the spectrum for therapeutic intervention.
International review of blood donation screening for anti‐HBc and occult hepatitis B virus infection
AbstractBackgroundHepatitis B core antibody (anti‐HBc) screening has been implemented in many blood establishments to help prevent transmission of hepatitis B virus (HBV), including from donors with occult HBV infection (OBI). We review HBV screening algorithms across blood establishments globally and their potential effectiveness in reducing transmission risk.Materials and MethodsA questionnaire on HBV screening and follow‐up strategies was distributed to members of the International Society of Blood Transfusion working party on transfusion‐transmitted infectious diseases. Screening data from 2022 were assimilated and analyzed.ResultsA total of 30 unique responses were received from 25 countries. Sixteen respondents screened all donations for anti‐HBc, with 14 also screening all donations for HBV DNA. Anti‐HBc prevalence was 0.42% in all blood donors and 1.19% in new donors in low‐endemic countries; however, only 44% of respondents performed additional anti‐HBc testing to exclude false reactivity. 0.68% of anti‐HBc positive, HBsAg‐negative donors had detectable HBV DNA. Ten respondents did universal HBV DNA screening without anti‐HBc, whereas four respondents did not screen for either. Deferral strategies for anti‐HBc positive donors were highly variable. One transfusion‐transmission from an anti‐HBc negative donor was reported.DiscussionAnti‐HBc screening identifies donors with OBI but also results in the unnecessary deferral of a significant number of donors with resolved HBV infection and donors with false‐reactive anti‐HBc results. Whilst confirmation of anti‐HBc results could be improved to reduce donor deferral, transmission risks associated with anti‐HBc negative OBI donors must be considered. In high‐endemic areas, highly sensitive HBV DNA testing is required to identify infectious donors.
Pneumococcal serotype epidemiology
This chapter summarizes the relative prevalences of the most common serotypes prior to and following the introduction of the heptavalent pneumococcal capsular polysaccharide vaccine (PCV-7). It provides thoughts about the selection of serotypes for future-generation conjugate vaccines. A remarkable feature of the global epidemiology of pneumococcal carriage is the consistency of the dominant carriage serotypes in very different environments and at different times. Invasive disease potential, or invasiveness, is a measure of the ability of pneumococci to progress from nasopharyngeal carriage to invasive disease in humans. It differs from virulence in that the latter is often used to describe the ability of a pathogen to cause disease in laboratory animals. The 11-valent formulation prevented vaccine-related otitis media and was also shown to elicit antibodies with functional immunogenicity (opsonophagocytic activity) against 6A comparable to that seen with PCV-7. The incidence of invasive pneumococcal disease (IPD) due to vaccine serotypes has decreased substantially since the introduction of PCV-7 in the United States, in vaccinated children as well as all other age groups, indicating that pneumococcal transmission was interrupted as a result of the reduction in carriage in the vaccinated pediatric population. For mucosal disease, otitis media and nonbacteremic pneumonia, it is less clear which serotypes it would be most valuable to add since there appear to be less clearcut differences in invasiveness among serotypes. The only certain way of preventing mucosal disease is to sterilize the nasopharynx with respect to pneumococci.
SARS-CoV-2 infection enhancement by amphotericin B: implications for disease management.
Severe coronavirus disease 2019 (COVID-19) patients who require hospitalization are at high risk of invasive pulmonary mucormycosis. Amphotericin B (AmB), which is the first-line therapy for invasive pulmonary mucormycosis, has been shown to promote or inhibit replication of a spectrum of viruses. In this study, we first predicted that AmB and nystatin had strong interactions with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) proteins using in silico screening, indicative of drugs with potential therapeutic activity against this virus. Subsequently, we investigated the impact of AmB, nystatin, natamycin, fluconazole, and caspofungin on SARS-CoV-2 infection and replication in vitro. Results showed that AmB and nystatin actually increased SARS-CoV-2 replication in Vero E6, Calu-3, and Huh7 cells. At optimal concentrations, AmB and nystatin increase SARS-CoV-2 replication by up to 100- and 10-fold in Vero E6 and Calu-3 cells, respectively. The other antifungals tested had no impact on SARS-CoV-2 infection in vitro. Drug kinetic studies indicate that AmB enhances SARS-CoV-2 infection by promoting viral entry into cells. Additionally, knockdown of genes encoding for interferon-induced transmembrane (IFITM) proteins 1, 2, and 3 suggests AmB enhances SARS-CoV-2 cell entry by overcoming the antiviral effect of the IFITM3 protein. This study further elucidates the role of IFITM3 in viral entry and highlights the potential dangers of treating COVID-19 patients, with invasive pulmonary mucormycosis, using AmB.IMPORTANCEAmB and nystatin are common treatments for fungal infections but were predicted to strongly interact with SARS-CoV-2 proteins, indicating their potential modulation or inhibition against the virus. However, our tests revealed that these antifungals, in fact, enhance SARS-CoV-2 infection by facilitating viral entry into cells. The magnitude of enhancement could be up to 10- or 100-fold, depending on cell lines used. These findings indicate that AmB and nystatin have the potential to enhance disease when given to patients infected with SARS-CoV-2 and therefore should not be used for treatment of fungal infections in active COVID-19 cases.
Impact of GLP-1 receptor agonist-induced weight loss on 22 cancers in the next ten years using a Markov state-transition model - A UK weight and wellness cancer landscape analysis.
BACKGROUND: Obesity is a major risk factor for many cancers. Glucagon-like peptide-1 receptor agonists (GLP-1RA) have emerged as highly effective agents for weight loss. There is a lack of published modelling studies describing the broader implications of GLP-1RA-induced weight loss on cancer incidence. METHODS: A Markov state-transition model was devised to evaluate the impact of GLP-1RA-induced weight loss on future cancer incidence in adults. Contemporary data on weight distribution, cancer incidence, and body mass index (BMI)-associated cancer risk were integrated into the model. Two scenarios were assessed, GLP-1RAs were made available to all people with obesity (BMI>30) or only those with severe obesity (BMI>35). New cancer cases were simulated over a decade. RESULTS: Our simulation within a closed cohort indicated that GLP-1RA-induced weight loss would lead to a marked decrease in cancer cases over 10 years in adults. If GLP-1RAs were made available for all people with obesity and 50 % of people with obesity moved into a lower BMI category, there was a simulated reduction in cumulative cancer cases of 21,443. If access to GLP-1RAs was restricted to people with severe obesity and 50 % of people with severe obesity moved into a lower BMI category, there was a simulated reduction in cumulative cancer cases of 7476. This effect was greatest for uterine, kidney, liver and colon cancer. CONCLUSION: Targeted weight control measures using GLP-1RAs could reduce new cancer cases. Based on our models, the potential risk of thyroid cancer is balanced by a reduction in other cancer types. This modelling study shows for the first time that implementing effective weight loss programmes could enhance the health of the population over the next decade through a reduction in cancer cases.
A pragmatic randomized controlled trial of standard care versus corticosteroids plus standard care for treatment of pneumonia in adults admitted to Kenyan hospitals (SONIA)
Background Mortality among adults admitted to hospital with community acquired pneumonia in resource-limited settings is high. Recent studies conducted in high-income settings have demonstrated beneficial effects of low-dose corticosteroids in reducing mortality in patients with severe community acquired pneumonia. It is unknown whether these findings apply to low-income settings such as sub-Saharan Africa. This pragmatic randomized-controlled open-label trial will determine the effect of adjunctive low-dose corticosteroids in the management of adults admitted to hospital with community acquired pneumonia on mortality 30-days post-randomization. Methods We will enroll and randomize 2180 patients admitted with a diagnosis of community acquired pneumonia into two arms: the control and intervention arm. Those in the control arm will receive standard care for the treatment of community acquired pneumonia i.e., combination therapy with a beta-lactam and macrolide antibiotic. Those in the intervention arm will receive up to 10-days treatment with low-dose oral corticosteroids in addition to standard care. All participants will be followed up to 30- days post randomization and their final status recorded (alive or dead). Discussion If adjunctive low-dose oral corticosteroids are found to be beneficial, this easily scalable intervention would significantly reduce the currently high mortality associated with community acquired pneumonia. Pan-African Clinical Trials Registry: PACTR202111481740832; ISRCTRN registry: ISRCTN36138594
The effect of COVID rehabilitation for ongoing symptoms Post HOSPitalisation with COVID-19 (PHOSP-R): protocol for a randomised parallel group controlled trial on behalf of the PHOSP consortium
Abstract Introduction Many adults hospitalised with COVID-19 have persistent symptoms such as fatigue, breathlessness and brain fog that limit day-to-day activities. These symptoms can last over 2 years. Whilst there is limited controlled studies on interventions that can support those with ongoing symptoms, there has been some promise in rehabilitation interventions in improving function and symptoms either using face-to-face or digital methods, but evidence remains limited and these studies often lack a control group. Methods and analysis This is a nested single-blind, parallel group, randomised control trial with embedded qualitative evaluation comparing rehabilitation (face-to-face or digital) to usual care and conducted within the PHOSP-COVID study. The aim of this study is to determine the effectiveness of rehabilitation interventions on exercise capacity, quality of life and symptoms such as breathlessness and fatigue. The primary outcome is the Incremental Shuttle Walking Test following the eight week intervention phase. Secondary outcomes include measures of function, strength and subjective assessment of symptoms. Blood inflammatory markers and muscle biopsies are an exploratory outcome. The interventions last eight weeks and combine symptom-titrated exercise therapy, symptom management and education delivered either in a face-to-face setting or through a digital platform (www.yourcovidrecovery.nhs.uk). The proposed sample size is 159 participants, and data will be intention-to-treat analyses comparing rehabilitation (face-to-face or digital) to usual care. Ethics and dissemination Ethical approval was gained as part of the PHOSP-COVID study by Yorkshire and the Humber Leeds West Research NHS Ethics Committee, and the study was prospectively registered on the ISRCTN trial registry (ISRCTN13293865). Results will be disseminated to stakeholders, including patients and members of the public, and published in appropriate journals. Article summary Strengths and limitations of this study • This protocol utilises two interventions to support those with ongoing symptoms of COVID-19 • This is a two-centre parallel-group randomised controlled trial • The protocol has been supported by patient and public involvement groups who identified treatments of symptoms and activity limitation as a top priority
CD4+ tissue-resident memory Th17 cells are a major source of IL-17A in Spondyloarthritis synovial tissue.
OBJECTIVES: Interleukin (IL)-17A is a key driver of spondyloarthritis (SpA) joint pathology. We aimed to identify its cellular source in synovial tissue from patients with 2 forms of SpA, namely axial SpA (AxSpA) and psoriatic arthritis (PsA). METHODS: Synovial tissue from patients with SpA was profiled using single-cell RNA sequencing (scRNA-seq; AxSpA, n = 5; PsA, n = 6) or spatial RNA profiling (PsA, n = 4). CellPhoneDB was used to infer cell-cell communication. Tissue-resident memory Th17 (TRM17)-like cells were generated in vitro using blood memory CD4+ T cells from SpA patients. An epigenetic inhibitor library, siRNA, and clustered regularly interspaced short palindromic repeats (CRISPR) were used to identify epigenetic regulator(s) for TRM17. RESULTS: scRNA-seq showed that CD4+CXCR6+ TRM17 cells are the predominant spontaneous IL17A producers in SpA synovium. Cell-cell communication and single-cell spatial analysis support the interaction between TRM17 and CLEC10A+ dendritic cells, which were activated in SpA. Both sublining and lining fibroblasts in SpA synovium showed evidence of interleukin (IL)-17A activation. In vitro-generated CD4+ TRM17-like cells phenocopied joint tissue TRM17, producing IL-17A/F upon T cell-receptor (TCR) stimulation, which was further enhanced by cytokines. Perturbation of BRD1 inhibited the generation of TRM17-like cells. CONCLUSIONS: CD4+ TRM17 cells are the predominant source of IL-17A in SpA synovial tissue. TCR stimulation is essential for the secretion of IL-17A by CD4+TRM17-like cells. The epigenetic regulator bromodomain-containing protein 1 (BRD1) contributes to the generation of CD4+TRM17. Depleting CD4+TRM17 cells in SpA is thus a therapeutic strategy with potential to induce long-term remission.
Early mucosal responses following a randomised controlled human inhaled infection with attenuated Mycobacterium bovis BCG.
The development of an effective vaccine against Mycobacterium tuberculosis is hampered by an incomplete understanding of immunoprotective mechanisms. We utilise an aerosol human challenge model using attenuated Mycobacterium bovis BCG, in BCG-naïve UK adults. The primary endpoint of this study (NCT03912207) was to characterise the early immune responses induced by aerosol BCG infection, the secondary endpoint was to identify immune markers associated with in-vitro protection. Blinded volunteers were randomised to inhale 1 × 107 CFU aerosolised BCG or 0.9% saline (20:6); and sequentially allocated to bronchoscopy at day 2 or 7 post-inhalation (10 BCG, 3 saline each timepoint). In the bronchoalveolar lavage post-aerosol BCG infection, there was an increase in frequency of eosinophils, neutrophils, NK cells and Donor-Unrestricted T cells at day 7, and the frequency of antigen presenting cells decreased at day 7 compared with day 2. The frequency of interferon-gamma+ BCG-specific CD4+ T cells increased in the BAL and peaked in the blood at day 7 post-BCG infection compared to day 2. BAL cells at day 2 and day 7 upregulated gene pathways related to phagocytosis, MHC-II antigen loading, T cell activation and proliferation. BCG's lack of key virulence factors and its failure to induce granulomas, may mean the observed immune responses do not fully recapitulate Mycobacterium tuberculosis infection. However, human infection models can provide unique insights into early immune mechanisms, informing vaccine design for complex pathogens.