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Purpose: Accurate surveillance of the COVID-19 pandemic can be weakened by under-reporting of cases, particularly due to asymptomatic or pre-symptomatic infections, resulting in bias. Quantification of SARS-CoV-2 RNA in wastewater (WW) can be used to infer infection prevalence, but uncertainty in sensitivity and considerable variability has meant that accurate measurement remains elusive. Methods & Materials: Data from 44 sewage sites in England, covering 31% of the population, are used in this analysis where samples are available from July 2020 to present day. Samples include the raw SARS-CoV-2 gene copy number and associated meta-data. To establish the sensitivity and specificity of the WW data, we compare to population representative prevalence surveys available across England (the ONS Covid Infection Survey - CIS). The WW data were mapped to sub-regional data of the CIS and fitted using mathematical modelling. First, a phenomenological model was developed to model how infected individuals shed SARS-CoV-2 into WW and how the markers may degrade in time and compare this to the data. Second, we develop a model to estimate SARS-CoV-2 prevalence directly from WW data which is trained on the CIS data. Results: Data from 44 sewage sites in England, shows that SARS-CoV-2 prevalence is estimated to within 1.1% of estimates from representative prevalence surveys (with 95% confidence). Using machine learning and phenomenological models, differences between sampled sites, particularly the WW flow rate, influence prevalence estimation and require careful interpretation. SARS-CoV-2 signals in WW appear 4-5 days earlier in comparison to clinical testing data but are coincident with prevalence surveys suggesting that WW surveillance can be a leading indicator for asymptomatic viral infections. Conclusion: Wastewater-based epidemiology complements and strengthens traditional surveillance, with significant implications for public health. Using WW to quantify infection prevalence requires knowledge of additional meta-data and outbreak detection needs to account for unexplained aberrations in WW data to improve reliability

Background: Syndromic surveillance often relies on patients presenting to healthcare. Community cohorts, although more challenging to recruit, could provide additional population-wide insights, particularly with SARS-CoV-2 co-circulating with other respiratory viruses., Methods: We estimated the positivity and incidence of SARS-CoV-2, influenza A/B, and RSV, and trends in self-reported symptoms including influenza-like illness (ILI), over the 2022/23 winter season in a broadly representative UK community cohort (COVID-19 Infection Survey), using negative-binomial generalised additive models. We estimated associations between test positivity and each of the symptoms and influenza vaccination, using adjusted logistic and multinomial models., Results: Swabs taken at 32,937/1,352,979 (2.4%) assessments tested positive for SARS-CoV-2, 181/14,939 (1.2%) for RSV and 130/14,939 (0.9%) for influenza A/B, varying by age over time. Positivity and incidence peaks were earliest for RSV, then influenza A/B, then SARS-CoV-2, and were highest for RSV in the youngest and for SARS-CoV-2 in the oldest age groups. Many test positives did not report key symptoms: middle-aged participants were generally more symptomatic than older or younger participants, but still, only ~ 25% reported ILI-WHO and ~ 60% ILI-ECDC. Most symptomatic participants did not test positive for any of the three viruses. Influenza A/B-positivity was lower in participants reporting influenza vaccination in the current and previous seasons (odds ratio = 0.55 (95% CI 0.32, 0.95)) versus neither season., Conclusions: Symptom profiles varied little by aetiology, making distinguishing SARS-CoV-2, influenza and RSV using symptoms challenging. Most symptoms were not explained by these viruses, indicating the importance of other pathogens in syndromic surveillance. Influenza vaccination was associated with lower rates of community influenza test positivity., (© 2024. The Author(s).)

Objective: To estimate the incidence and HRs for bleeding for different dual antiplatelet therapies (DAPT) in a real-world population with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) in England., Design: A retrospective, population-based cohort study emulating a target randomised controlled trial (tRCT)., Data Sources: Linked Clinical Practice Research Datalink (CPRD) and Hospital Episode Statistics (HES)., Setting: Primary and secondary care., Participants: Patients ≥18 years old with ACS undergoing emergency PCI., Interventions: Aspirin and clopidogrel (AC, reference) versus aspirin and prasugrel (AP) or aspirin and ticagrelor (AT); AP evaluated only in patients with ST-elevation myocardial infarction (STEMI)., Main Outcome Measures: Primary: any bleeding up to 12 months after the index event (HES- or CPRD- recorded). Secondary: HES-recorded bleeding, CPRD-recorded bleeding, all-cause and cardiovascular mortality, mortality from bleeding, myocardial infarction, stroke, additional coronary intervention and major adverse cardiovascular and cerebrovascular events (MACCE)., Results: In ACS, the rates of any bleeding for AC and AT were 89 per 1000 person years and 134 per 1000 person years, respectively. In STEMI, rates for AC, AP and AT were 93 per 1000 person years, 138 per 1000 person years and 143 per 100 person years, respectively. In ACS, compared with AC, AT increased the hazard of any bleeding (HR: 1.47, 95% CI 1.19 to 1.82) but did not reduce MACCE (HR: 1.06, 95% CI 0.89 to 1.27). In STEMI, compared with AC, AP and AT increased the hazard of any bleeding (HR: 1.77, 95% CI 1.21 to 2.59 and HR: 1.50, 95% CI 1.10 to 2.05, respectively) but did not reduce MACCE (HR: 1.10, 95% CI 0.80 to 1.51 and HR: 1.21, 95% CI 0.94 to 1.51, respectively). Non-adherence to the prescribed DAPT regimen was 28% in AC (29% in STEMI only), 31% in AP (STEMI only) and 33% in AT (32% in STEMI only)., Conclusions: In a real-world population with ACS, DAPT with ticagrelor or prasugrel are associated with increased bleeding compared with DAPT with clopidogrel., Trial Registration Number: ISRCTN76607611., Competing Interests: Competing interests: TWJ reports grants, personal fees and other from AstraZeneca and Bayer, personal fees and other from Daiichi Sankyo and personal fees from The Medicines Company, outside the submitted work., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY. Published by BMJ.)

Accurate surveillance of the COVID-19 pandemic can be weakened by under-reporting of cases, particularly due to asymptomatic or pre-symptomatic infections, resulting in bias. Quantification of SARS-CoV-2 RNA in wastewater can be used to infer infection prevalence, but uncertainty in sensitivity and considerable variability has meant that accurate measurement remains elusive. Here, we use data from 45 sewage sites in England, covering 31% of the population, and estimate SARS-CoV-2 prevalence to within 1.1% of estimates from representative prevalence surveys (with 95% confidence). Using machine learning and phenomenological models, we show that differences between sampled sites, particularly the wastewater flow rate, influence prevalence estimation and require careful interpretation. We find that SARS-CoV-2 signals in wastewater appear 4-5 days earlier in comparison to clinical testing data but are coincident with prevalence surveys suggesting that wastewater surveillance can be a leading indicator for symptomatic viral infections. Surveillance for viruses in wastewater complements and strengthens clinical surveillance, with significant implications for public health., (© 2022. Crown.)

Background: In 2017, approximately 73% of antibiotics in England were prescribed from primary care practices. It has been estimated that 9%-23% of antibiotic prescriptions between 2013 and 2015 were inappropriate. Reducing antibiotic prescribing in primary care was included as one of the national priorities in a financial incentive scheme in 2015-2016., Aim: To investigate whether the effects of the Quality Premium (QP), which provided performance-related financial incentives to clinical commissioning groups (CCGs), could be explained by practice characteristics that contribute to variations in antibiotic prescribing., Design & Setting: Longitudinal monthly prescribing data were analysed for 6251 primary care practices in England from April 2014 to March 2016., Method: Linear generalised estimating equations models were fitted, examining the effect of the 2015-2016 QP on the number of antibiotic items per specific therapeutic group age-sex related prescribing unit (STAR-PU) prescribed, adjusting for seasonality and months since implementation. Consistency of effects after further adjustment for variations in practice characteristics were also examined, including practice workforce, comorbidities prevalence, prescribing rates of non-antibiotic drugs, and deprivation., Results: Antibiotics prescribed in primary care practices in England reduced by -0.172 items per STAR-PU (95% confidence interval [CI] = -0.180 to -0.171) after 2015-2016 QP implementation, with slight increases in the months following April 2015 (+0.014 items per STAR-PU; 95% CI = +0.013 to +0.014). Adjusting the model for practice characteristics, the immediate and month-on-month effects following implementation remained consistent, with slight attenuation in immediate reduction from -0.172 to -0.166 items per STAR-PU. In subgroup analysis, the QP effect was significantly greater among the top 20% prescribing practices (interaction p <0.001). Practices with low workforce and those with higher diabetes prevalence had greater reductions in prescribing following 2015-2016 QP compared with other practices (interaction p <0.001)., Conclusion: In high-prescribing practices, those with low workforce and high diabetes prevalence had more reduction following the QP compared with other practices, highlighting the need for targeted support of these practices and appropriate resourcing of primary care., (Copyright © 2020, The Authors.)

To date, constitutively activating point mutations reported in hematopoietic growth factor receptors in patients with acute myeloid leukemia (AML) have been restricted to receptors with intrinsic tyrosine kinase activity such as c-kit and FLT3. We describe here a Thr617Asn mutation in the transmembrane domain of the non-tyrosine kinase receptor for granulocyte colony-stimulating factor (G-CSF) in the blast cells of two out of 555 AML patients examined. The mutant receptor conferred growth factor independence on factor-dependent Ba/F3 cells. In the absence of ligand, immunoblotting showed weak phosphorylation of JAK2, STAT3, ERKs 1 and 2 and the receptor itself, and there was approximately 70% of maximal growth in a proliferation assay. All signals were significantly enhanced in the presence of G-CSF. Retroviral transduction of mutant receptor into primary hematopoietic CD34+ cells induced G-CSF independent myeloid differentiation as assessed by the development of neutrophils and surface expression of CD11b and CD14. These results confirm the importance of the transmembrane domain for receptor function and suggest that introduction of an asparagine residue can cause sufficient stabilization of helix-helix interactions in the absence of ligand to activate downstream signaling pathways involved in directing proliferation and differentiation.

A subset of leukemic cells is assumed to maintain long-term growth of acute myeloid leukemia (AML) in vivo. Characterization of these AML progenitor cells may further define growth properties of human leukemia. In vitro incubations with 5-fluorouracil (5-FU) have been used for enrichment of normal primitive hematopoietic stem cells. By analogy to normal hematopoiesis, it was hypothesized that primitive leukemic stem cells might be kinetically more inactive than colony-forming cells (colony-forming units-AML [CFU-AML]). To examine this hypothesis, conditions were established for incubation with 5-FU that eliminated all CFU-AML. These conditions selected a 5-FU-resistant AML fraction that was evaluated for its capacity for long-term growth by transplantation into mice with severe combined immunodeficiency (SCID) and long-term culture in the quantitative cobblestone area-forming cell (CAFC) assay. Transplantation of the 5-FU-resistant fraction of four cases of AML into SCID mice resulted in growth of AML. Whereas no CFU-AML survived, 31% to 82% of primitive (week-6) CAFC were recovered from the 5-FU-treated cells. Hematopoietic cells proliferating in the CAFC assay were shown to be leukemic by cytologic, cytogenetic, or molecular analysis. The reduction of AML growth as determined by outgrowth of AML in SCID mice was in the same order of magnitude as the primitive (week-6) CAFC reduction. This indicates that both assays measure closely related cell populations and that the CAFC assay can be used to study long-term growth of AML. These results show a hierarchy of AML cells that includes 5-FU-resistant progenitors. These cells are characterized as primitive (week-6) CAFC and as leukemia-initiating cells in SCID mice.

Interleukin-7 (IL-7) stimulates the proliferation of normal and leukemic B and T cell precursors and T lymphocytes. Activation of the JAK/STAT pathway has been implicated in IL-7R signaling. We investigated which STAT complexes are formed upon stimulation of B cell precursor acute lymphoblastic leukemia (BCP-ALL) cells with IL-7. Gel retardation assays with STAT-binding oligonucleotides showed that IL-7 induces the formation of two major STAT complexes in BCP-ALL cells. Supershifts with anti-STAT antibodies identified these as STAT1 and STAT5 complexes. This pattern of STAT activation was seen in all BCP-ALL cases that respond to IL-7 in proliferation assays. IL-7 also induced STAT/DNA binding in BCP-ALL cases that failed to proliferate in response to IL-7, suggesting that the ability of IL-7R to activate the JAK/STAT pathway per se is not sufficient for proliferation induction. To determine the contribution of the cytoplasmic domain of the IL-7 receptor alpha chain (IL-7R alpha) to activation of STAT proteins, transfectants of the murine pro-B cell line BAF3 were made that express chimeric receptors consisting of the extracellular domain of human granulocyte colony-stimulating factor receptor (G-CSF-R) and the transmembrane and intracellular domains of human IL-7R alpha. Activation of the chimeric G-CSF-R/IL-7R alpha with G-CSF resulted in a full proliferative response and induced the phosphorylation of JAK1 but not JAK2. Major STAT complexes activated by G-CSF-R/IL-7R alpha contained STAT1 or STAT5, while some formation of STAT3-containing complexes was also seen. These findings establish that STAT1 and STAT5, and possibly STAT3, are activated upon stimulation of precursor B cells with IL-7. The data further indicate that the IL-7R alpha chains are directly involved in the activation of JAKs and STATs and have a major role in proliferative signaling in precursor B cells.

Granulocyte colony-stimulating factor (G-CSF) induces rapid phosphorylation of JAK kinases as well as activation of the p21ras route through interaction with its specific receptor (G-CSF-R). The cytoplasmic membrane-proximal region of G-CSF-R (amino acids 631 to 684) is necessary for proliferation induction and activation of JAK2. In contrast, activation of Shc and Syp, signaling molecules implicated in the p21ras signaling route, depends on the phosphorylation of tyrosine residues located in the membrane-distal region (amino acids 685 to 813) of G-CSF-R. We investigated whether G-CSF-induced activation of signaling complexes of the p21ras route depends on the function of the membrane-proximal cytoplasmic region of G-CSF-R. A G-CSF-R mutant was constructed in which tryptophan 650 was replaced by arginine and expressed in BAF3 cells (BAF/W650R). In contrast to BAF3 cell transfectants expressing wild-type G-CSF-R, BAF/W650-R cells did not proliferate and did not show activation of JAK2, STAT1, or STAT3 in response to G-CSF. Immunoprecipitations with anti-Shc and anti-Grb2 antisera showed that mutant W650R also failed to activate Syp and Shc. These data indicate that the membrane-proximal cytoplasmic domain of G-CSF-R is not only crucial for proliferative signaling and activation of JAK2 and STATs, but is also required for activation of the p21ras route, which occurs via the membrane-distal region of G-CSF-R.

Granulocyte colony-stimulating factor (G-CSF) promotes the survival and proliferation of myeloid progenitors and induces maturation of these cells toward terminally differentiated neutrophils. Using transfectants of the murine IL-3-dependent myeloid cell line 32D that express the human G-CSF receptor (32D/WT cells), we show here that G-CSF can also exert adverse effects on myeloid cell survival. Although initially enhancing IL-3-driven proliferation of 32D/WT cells, G-CSF strongly inhibited cell survival at later stages of culture. The loss of viability of 32D/WT cells following sustained G-CSF stimulation was not accompanied by progressive neutrophilic maturation. Instead, 32D/WT cells exhibited features characteristic of apoptosis. The apoptosis-inducing effect of G-CSF was seen at concentrations of IL-3 that could support long-term proliferation and survival of 32D/WT cells in the absence of G-CSF. Experiments with 32D cells expressing mutant forms of the G-CSF receptor revealed that the death signals were mediated exclusively through the membrane-distal cytoplasmic part of the G-CSF receptor, a region also involved in maturation signaling.

Interleukin 7 (IL-7) stimulates proliferation of normal human and murine B cell precursor (BCP) cells in a distinct fashion, depending on the stage of maturation of the cells. For instance, the productive rearrangement of the immunoglobulin heavy chain gene has been demonstrated to be essential for the response of BCP cells to IL-7 as the single proliferation stimulus. IL-7 activates a receptor that consists of the IL-7R protein and the common gamma chain (gamma c). BCP acute lymphoblastic leukemia (BCP-ALL) cells variably respond to IL-7. Among 72 cases of BCP-ALL IL-7 activated DNA synthesis in 34. In four cases inhibition of DNA synthesis was seen. In the remaining 38 cases IL-7 exerted no effects. We determined whether this heterogeneity in IL-7 response could be correlated with parameters that could influence the IL-7 response. Firstly we show that, in contrast to the murine BCP cells, the IL-7 response of human BCP-ALL cells did not correlate with the status of IgH chain gene rearrangement and expression, nor with the rearrangement of IgL chain genes. Subsequently, it is demonstrated that IL-7R protein and transcripts as well as gamma c transcripts are equally present in the IL-7 responsive and nonresponsive BCP-ALL samples, indicating that the defective expression of these chains could not be held responsible for IL-7 response failures. Finally, we observed that kit ligand (KL), known to synergize with IL-7 in the most primitive stages of normal B cell development, did not enhance the IL-7 responses of BCP-ALL cells.

The granulocyte colony-stimulating factor receptor (G-CSF-R) transduces signals important for the proliferation and maturation of myeloid progenitor cells. To identify functionally important regions in the cytoplasmic domain of the G-CSF-R, we compared the actions of the wild-type receptor, two mutants, and a natural splice variant in transfectants of the mouse pro-B cell line BAF3 and two myeloid cell lines, 32D and L-GM. A region of 55 amino acids adjacent to the transmembrane domain was found to be sufficient for generating a growth signal. The immediate downstream sequence of 30 amino acids substantially enhanced the growth signaling in the three cell lines. In contrast, the carboxy-terminal part of 98 amino acids strongly inhibited growth signaling in the two myeloid cell lines but not in BAF3 cells. Truncation of this region lead to an inability of the G-CSF-R to transduce maturation signals in L-GM cells. An alternative carboxy tail present in a splice variant of the G-CSF-R also inhibited growth signaling, notably in both the myeloid cells and BAF3 cells, but appeared not to be involved in maturation.

Acute myeloid leukemia blasts express dual affinity (high and low) granulocyte-macrophage colony-stimulating factor (GM-CSF) binding, and the high affinity GM-CSF binding is counteracted by excess interleukin-3 (IL-3). Neutrophils express a single class of GM-CSF-R with intermediate affinity that lack IL-3 cross-reactivity. Here we demonstrate the differentiation associated changes of GM-CSF binding characteristics in three models representative of different stages of myeloid maturation. We find that high affinity GM-CSF binding is converted into intermediate affinity binding, which still cross-reacts with IL-3, beyond the stage of promyelocytes. During terminal maturation towards neutrophils, IL-3 cross-reactivity is gradually lost. We sought to determine the mechanism underlying the affinity conversion of the GM-CSF-R. Northern and reverse transcriptase-polymerase chain reaction analysis of GM-CSF-R alpha and -beta c (KH97) transcripts did not provide indications for the involvement of GM-CSF-R splice variants in the formation of the intermediate affinity GM-CSFR complex. In COS-cell transfectants with increasing amounts of beta c in the presence of a fixed number of GM-CSF-R alpha chains, the high affinity GM-CSF binding converted into intermediate affinity GM-CSF binding. These results are discussed in view of the concept that increasing expression of beta c subunits may cause alternative oligomerization of the GM-CSF-R alpha and -beta c subunits resulting in the formation of intermediate rather than high affinity GM-CSFR alpha.beta c complexes.

Among 52 patients diagnosed as acute myeloid leukemia (AML), nine cases were found in which interleukin-5 (IL-5) induced a proliferative response in the leukemic cells, as measured by the stimulation of DNA synthesis or colony formation in vitro. All cases (n = 7) with the cytogenetic abnormality t(8;21)(q22;q22) belonged to this group of IL-5 responders. Of the additional two cases, one had an apparently normal karyotype, but the other expressed a dicentric chromosome 21, an abnormality also involving the breakpoint region 21q22. The leukemic cells of the IL-5 responsive patients could also be stimulated to proliferate by IL-3, GM-CSF and G-CSF, and in some cases by IL-6 or M-CSF. Immunophenotypic analysis revealed the presence of the immature hematopoietic cell antigen CD34, the myelomonocytic maturation antigens CD13 and CD33, in association with the B-cell related surface marker CD19 on the leukemic cells. Immunoglobulin mu and T-cell receptor beta-genes in the leukemic cells were in germline configuration. Upon incubation in colony culture, clonogenic cells were capable of producing progeny showing eosinophilic or neutrophilic maturation following stimulation with IL-5 or G-CSF, respectively. It is concluded that IL-5 responsive AML represents a subgroup of leukemia with distinct immunotypic and cytogenetic features.

We investigated the proliferation-inducing effects of human recombinant interleukin-7 (IL-7) on acute lymphoblastic leukemia (ALL) cells. It is shown that IL-7 stimulates DNA synthesis in ALL cells of B-cell precursor (n = 5) as well as immature T-cell origin (n = 2). Cytogenetic analysis of the cells of four patients proliferating in IL7-supplemented cultures established the leukemic descendence of the IL-7-responsive cells. 125I-IL-7 binding experiments with the cells of one patient and with two ALL cell lines showed the presence of two types of IL-7 receptors: one with a high affinity (kd 29 to 51 pmol/L) and one with a low affinity (kd 2.3 to 76 nmol/L) for the ligand. We conclude that IL-7 is one of the cytokines involved in the complex regulation of ALL cell proliferation.