Hematopoietic stem cells (HSCs) are a population of tissue-specific stem cells that reside in the bone marrow of adult mammals where they self-renew and continuously regenerate the adult hematopoietic lineages over the life of the individual. Prominence as a stem cell model and clinical usefulness has driven interest in understanding the physiological processes that lead to specification of HSCs during embryonic development. High efficiency directed differentiation of HSCs by instruction of defined progenitor cells using sequentially defined instructive molecules and conditions remains impossible, indicating that comprehensive knowledge of the complete set of precursor intermediate identities and required inductive inputs remains incompletely understood. Recently, interest in the molecular and cellular microenvironment where HSCs are specified from endothelial precursors—the “specification niche”—has increased. Here we review recent progress in understanding these niche spaces across vertebrate phyla, as well as how a better characterization of the origin and molecular phenotypes of the niche cell populations has helped inform and complicate previous understanding of signaling required for HSC emergence and maturation.

Cilia defects lead to scoliosis in zebrafish, but the underlying pathogenic mechanisms are poorly understood and may diverge depending on the mutated gene. Here, we dissected the mechanisms of scoliosis onset in a zebrafish mutant for the rpgrip1l gene encoding a ciliary transition zone protein. rpgrip1l mutant fish developed scoliosis with near-total penetrance but asynchronous onset in juveniles. Taking advantage of this asynchrony, we found that curvature onset was preceded by ventricle dilations and was concomitant to the perturbation of Reissner fiber polymerization and to the loss of multiciliated tufts around the subcommissural organ. Rescue experiments showed that Rpgrip1l was exclusively required in foxj1a-expressing cells to prevent axis curvature. Genetic interactions investigations ruled out Urp1/2 levels as a main driver of scoliosis in rpgrip1 mutants. Transcriptomic and proteomic studies identified neuroinflammation associated with increased Annexin levels as a potential mechanism of scoliosis development in rpgrip1l juveniles. Investigating the cell types associated with annexin2 over-expression, we uncovered astrogliosis, arising in glial cells surrounding the diencephalic and rhombencephalic ventricles just before scoliosis onset and increasing with time in severity. Anti-inflammatory drug treatment reduced scoliosis penetrance and severity and this correlated with reduced astrogliosis and macrophage/microglia enrichment around the diencephalic ventricle. Mutation of the cep290 gene encoding another transition zone protein also associated astrogliosis with scoliosis. Thus, we propose astrogliosis induced by perturbed ventricular homeostasis and associated with immune cell activation as a novel pathogenic mechanism of zebrafish scoliosis caused by cilia dysfunction.

Introduction The introduction of effective human papillomavirus (HPV) vaccination, screening, and treatment programs has led the World Health Organization to call for the global elimination of cervical cancer. Assessing progress toward this goal is supported through monitoring vaccination coverage and its impact.Areas covered We performed a targeted review to assess the characteristics of HPV-related data systems from seven high-income countries (HICs) that represented varied approaches, including Australia, Canada, France, Italy, Scotland, Sweden, and the United States (US). Included data systems focused on preventive and early detection measures: HPV vaccination and cervical screening programs, as well as HPV-related disease outcomes. Differences were observed in approach to development of data systems, along with variation in geographical scope and methods of data collection.Expert opinion A challenge exists in how to best follow-up the ongoing global-scale elimination efforts in a comprehensive manner. These sources provide a wealth of information regarding the strengths and limitations of, and notable variation among, current data systems used in HICs. This review can inform improvements to existing prevention programs and the implementation of new programs in other countries, and thus support optimization of cervical cancer prevention policy.

e19072 Background: This study aimed to provide a comprehensive overview of the evidence available on drug-induced myelosuppression in patients with MDS or AML. Methods: A systematic literature review (SLR) was conducted using MEDLINE, Embase, and Cochrane to identify studies published 2002-2022 explicitly targeting drug-induced myelosuppression with current and emerging treatments used for MDS and/or AML (venetoclax [VEN], azacitidine [AZA], magrolimab, sabatolimab, decitabine [DEC], cedazuridine, lenalidomide [LEN], low-dose cytarabine [LDAC], intensive chemotherapy [IC]) in terms of drug-induced AEs, treatment discontinuation, QOL, and MRU. Article selection was based on predefined eligibility criteria (PICO+ framework), with a focus on specific geographic regions (USA, UK, Spain, Italy, France, Germany). Results: A total of 48 studies reporting on VEN, AZA, DEC, LEN, LDAC, and IC based regimens met the inclusion criteria. In MDS populations, myelotoxicity was reported in all blood cell lineages in association with AZA, DEC, and LEN monotherapies. In AML populations, myelosuppression was reported in all blood cell lineages in association with all regimens except LEN. In general, the reported incidence of myelosuppressive AEs was higher in studies published prior to 2010 and in studies of patients with AML or MDS who had received prior treatments vs more recent studies (2018-2022) and studies of treatment-naive patients, respectively. Differences observed between the two time periods might be explained by improved supportive care (AEs prophylaxis and management). In treatment-naive AML populations, the incidence of any-grade febrile neutropenia, leukopenia, and anemia was up to 3-fold higher with AZA combination therapy vs monotherapy, and the incidence of any-grade neutropenia and febrile neutropenia was 2-fold higher with LDAC combination regimens vs monotherapy, suggestive of an additive effect. The most common reasons for treatment discontinuation were AEs and disease progression. QOL significantly improved with AZA monotherapy; however, hematologic improvement was not explicitly mentioned as the main driver. There were no data on combination therapies to indicate whether the improvement in QOL compensated for the added drug-induced AEs. The few studies that reported on the impact of myelosuppression on MRU did not provide conclusive results. Conclusions: This SLR suggests that combining ≥2 myelosuppressive drugs may result in increased toxicity; however, the lack of evidence on the impact of myelotoxicity on QOL and MRU with ≥2 myelosuppressive drugs limits informed decision-making in routine clinical practice. Further research is needed to explore the impact of drug-induced myelosuppression in patients with MDS or AML.

Topic: 10. Myelodysplastic syndromes - Clinical Background: Adverse events (AEs) associated with drug-induced myelosuppression are of substantial concern when treating patients with hematologic malignancies, especially with combination therapies. Aims: This study aimed to provide a comprehensive overview of the evidence available on drug-induced myelosuppression in patients with myelodysplastic syndromes (MDS) or acute myeloid leukemia (AML). Methods: A systematic literature review (SLR) was conducted using MEDLINE, Embase, and Cochrane to identify studies published in 2002-2022, explicitly targeting drug-induced myelosuppression with current and emerging treatments for MDS and/or AML (venetoclax [VEN], azacitidine [AZA], magrolimab, sabatolimab, decitabine [DEC], cedazuridine, lenalidomide [LEN], low-dose cytarabine [LDAC], intensive chemotherapy [IC]) in terms of drug-induced AEs, treatment discontinuation, quality of life (QOL), and medical resource use (MRU). Articles were selected based on predefined eligibility criteria (PICO+ framework), with a focus on specific countries (US, UK, Spain, Italy, France, Germany). Results: A total of 48 studies reporting on VEN-, AZA-, DEC-, LEN-, LDAC-, and IC-based regimens met the inclusion criteria. In MDS populations, myelotoxicity associated with AZA, DEC, and LEN monotherapies was reported in all blood cell lineages. In AML populations, myelosuppression associated with all regimens except LEN was reported in all blood cell lineages. In general, the reported incidence of myelosuppressive AEs was higher in studies published prior to 2010 vs more recently (2018-2022) and in studies in patients with AML or MDS who had received prior treatment vs treatment-naive patients. Differences between the two time periods might be explained by improved supportive care (AE prophylaxis and management). In treatment-naive AML populations, the incidence of any-grade febrile neutropenia, leukopenia, and anemia was up to 3-fold higher with AZA combination therapy vs monotherapy, and the incidence of any-grade neutropenia and febrile neutropenia was 2-fold higher with LDAC combination regimens vs monotherapy, suggesting an additive effect. The most common reasons for treatment discontinuation were AEs and disease progression. QOL was significantly improved with AZA monotherapy; however, hematologic improvement was not explicitly mentioned as the main driver. There were no data on combination therapies to indicate whether the improvement in QOL compensated for the added drug-induced AEs. The few studies that reported on the impact of myelosuppression on MRU did not provide conclusive results. Summary/Conclusion: This SLR suggests that combining ≥2 myelosuppressive drugs may result in increased toxicity; however, the lack of evidence on the impact of myelotoxicity on QOL and MRU with ≥2 myelosuppressive drugs limits informed decision-making in routine clinical practice. Further research is needed to explore the impact of drug-induced myelosuppression in patients with MDS or AML. Keywords: Systematic review, MDS/AML, Myelosuppression

Hematopoietic stem cells (HSCs) continuously replenish the hematopoietic system and form the basis of transplant therapies for hematologic and autoimmune diseases. In vertebrates, HSCs are developmentally specified from a transient population of specialized endothelial cells known as hemogenic endothelium (HE) located in the floor of the dorsal aorta. Under the influence of intrinsic and extrinsic differentiation cues, HE cells lose their endothelial fate and acquire hematopoietic identity through an endothelial-to-hematopoietic transition (EHT). Decades of intensive study have identified key peptide signals required for HSC specification, but a complete understanding remains elusive. Extracellular matrix (ECM) is a major component of the HSC inductive environment able both to signal directly and also regulate display of known signaling factors, but few or no studies have directly addressed the role of ECM in HSC specification. Collagen, the most abundant protein in vertebrates, forms the structural backbone of ECM and its maturation into stiffened fibers is regulated by Plod2 (Lysyl Hydroxylase 2), which catalyzes hydroxylation of key collagen lysines as a precondition to fibril crosslinking. Plod2 thus regulates ECM stability, permeability, and stiffness, and has previous roles described in malignant epithelial-to-mesenchymal transition (EMT) and metastasis. We have performed in vivo expression and functional studies in the zebrafish model. Our data show that plod2 is expressed in tissues adjacent to the dorsal aorta at the time of EHT, while plod2 loss-of-function by targeted deletion or antisense abrogates emergence of HSCs in the AGM. We are currently extending our findings to mammals. Our studies identify ECM architecture and its enzymatic regulation as central to the establishment of definitive hematopoiesis. Hematopoietic stem cells (HSCs) continuously replenish the hematopoietic system and form the basis of transplant therapies for hematologic and autoimmune diseases. In vertebrates, HSCs are developmentally specified from a transient population of specialized endothelial cells known as hemogenic endothelium (HE) located in the floor of the dorsal aorta. Under the influence of intrinsic and extrinsic differentiation cues, HE cells lose their endothelial fate and acquire hematopoietic identity through an endothelial-to-hematopoietic transition (EHT). Decades of intensive study have identified key peptide signals required for HSC specification, but a complete understanding remains elusive. Extracellular matrix (ECM) is a major component of the HSC inductive environment able both to signal directly and also regulate display of known signaling factors, but few or no studies have directly addressed the role of ECM in HSC specification. Collagen, the most abundant protein in vertebrates, forms the structural backbone of ECM and its maturation into stiffened fibers is regulated by Plod2 (Lysyl Hydroxylase 2), which catalyzes hydroxylation of key collagen lysines as a precondition to fibril crosslinking. Plod2 thus regulates ECM stability, permeability, and stiffness, and has previous roles described in malignant epithelial-to-mesenchymal transition (EMT) and metastasis. We have performed in vivo expression and functional studies in the zebrafish model. Our data show that plod2 is expressed in tissues adjacent to the dorsal aorta at the time of EHT, while plod2 loss-of-function by targeted deletion or antisense abrogates emergence of HSCs in the AGM. We are currently extending our findings to mammals. Our studies identify ECM architecture and its enzymatic regulation as central to the establishment of definitive hematopoiesis.

Background: The extent of cross-protection provided by currently licensed bivalent and quadrivalent HPV vaccines versus direct protection against HPV 31-, 33-, 45-, 52-, and 58-related disease is debated. A systematic literature review was conducted to establish the duration and magnitude of cross-protection in interventional and observational studies. Methods: PubMed and Embase databases were searched to identify randomized controlled trials (RCT) and observational studies published between 2008 and 2019 reporting on efficacy and effectiveness of HPV vaccines in women against non-vaccine types 31, 33, 45, 52, 58, and 6 and 11 (non-bivalent types). Key outcomes of interest were vaccine efficacy against 6- and 12-month persistent infection or genital lesions, and type-specific genital HPV prevalence or incidence. RCT data were analyzed for the according-to-protocol (bivalent vaccine) or negative-for-14-HPV-types (quadrivalent vaccine) efficacy cohorts. Results: Data from 23 RCTs and 33 observational studies evaluating cross-protection were extracted. RCTs assessed cross-protection in post-hoc analyses of small size subgroups. Among fully vaccinated, baseline HPV-naive women, the bivalent vaccine showed statistically significant cross-protective efficacy, although with wide confidence intervals, against 6-month and 12-month persistent cervical infections and CIN2+ only consistently for HPV 31 and 45, with the highest effect observed for HPV 31 (range 64.6% [95% CI: 27.6 to 83.9] to 79.1% [97.7% CI: 27.6 to 95.9] for 6-month persistent infection; maximal follow-up 4.7 years). No cross-protection was shown in extended follow-up. The quadrivalent vaccine efficacy reached statistical significance for HPV 31 (46.2% [15.3-66.4]; follow-up: 3.6 years). Similarly, observational studies found consistently significant effectiveness only against HPV 31 and 45 with both vaccines. Conclusions: RCTs and observational studies show that cross-protection is inconsistent across non-vaccine HPV types and is largely driven by HPV 31 and 45. Furthermore, existing data suggest that it wanes over time; its long-term durability has not been established. (C) 2020 Published by Elsevier Ltd.

Objective The objective of this exploratory analysis is to reflect and discuss which criteria of multiple criteria decision analysis (MCDA) would be relevant as part of value determination when appraising healthcare interventions in the Lebanese context. Methods A workshop was conducted as part of the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) Lebanon Chapter and included the two frameworks: Evidence and Value: Impact on Decision Making (EVIDEM) and Advance Value Framework. Thirty-seven participants expressed their individual preferences through a qualitative and a quantitative exercise. Results In the qualitative analysis of both frameworks, participants unanimously agreed on the relevance of comparative efficacy, safety, and impact of medical costs. In EVIDEM, disease severity and unmet needs were also considered to be important criteria by more than 90 percent of the participants. In the quantitative analysis of both frameworks, disease severity ranked first (a mean normalized weight of .1 in EVIDEM and .27 in Advance Value Framework), followed by the size of the population (.09), the type of therapeutic benefit at the patient level (.09) and population level (.08), and the efficacy (.07) in EVIDEM. In the Advance Value Framework, the combined unmet need/disease severity criteria were followed by direct and meaningful end points (.15), safety (.12), contraindications (.08), and indirect surrogate end points (.07). Conclusions The results were concordant with those reported in countries that have conducted similar surveys such as France, Italy, and Spain. The MCDA methodology could be used as a cornerstone to enhance evidence-based discussions among Lebanese stakeholders involved in evaluation and decision-making purposes.

Introduction: Studies on the cross-protective effect of HPV bivalent and quadrivalent vaccines demonstrated inconsistent findings against additional HPV types covered by the nonavalent vaccine. The objective of this study was to conduct a systematic literature review to assess the consistency and durability of the cross-protective neutralizing antibody immune responses of the currently licensed bivalent and quadrivalent vaccines to non-vaccine HPV types targeted by the nonavalent vaccine (HPV 6, 11, 31, 33, 45, 52, and 58). Methods: PubMed and EMBASE databases were searched from 2008 to 2019 to identify studies reporting antibody/immune response after vaccination with either the bivalent, quadrivalent, or nonavalent vaccine. Key outcomes were seroconversion, seropositivity or geometric mean titers against HPV types 6, 11, 31, 33, 45, 52, and 58. Results: Eighteen publications met inclusion criteria, reporting on 14 interventional and five observational studies. Across all studies, immune responses to non-vaccine high-risk HPV types after bivalent vaccination were higher than baseline or quadrivalent vaccine. Nonavalent vaccine elicited near total seroconversion to HPV types 31, 33, 45, 52, and 58, with seropositivity remaining near 100% up to 24 months post-dose 1. In contrast, bivalent and quadrivalent vaccination resulted in lower seroconversion levels for non-vaccine types, which waned over time. Conclusions: The cross-protection antibody/immune response among participants having received all three doses of bivalent or quadrivalent vaccine is not comparable to the specific response elicited by HPV vaccine types. Even in cases where a statistically significant cross-reactive immunological response is reported, long-term data on the duration of the response beyond two years are very limited. Further, the lack of a standard for assays limits comparability of results between studies. (C) 2021 Published by Elsevier Ltd.

The Multi-criteria decision analysis (MCDA) approach has been promoted as a mean to support systematic consideration of a broad range of decision criteria when appraising healthcare interventions. While it is important to capture all relevant aspects of value, these may not be fully transferable without considering country-specific aspects. The objective of this exploratory analysis is to discuss which criteria would be relevant in value determination for a pharmaceutical product in the Lebanese context. A face-to-face workshop was conducted as part of ISPOR Lebanon Chapter in February 2019 and included a presentation of the concept of MCDA and the two frameworks, EVIDEM and ADVANCE. During the workshop, 37 participants expressed their individual preferences through interactive exercises comprising of a qualitative exploration of criteria and their relevance in decision making and a quantitative exercise aiming at ranking (weighting) the different criteria to reflect their relative importance. In the qualitative analysis of both frameworks, participants unanimously agreed on the relevance of comparative efficacy, safety, impact of medical costs. In EVIDEM, disease severity and unmet needs were also considered to be important criteria by more than 90% of the participants. In the quantitative analysis of both frameworks, disease severity ranked first (mean normalized weight of 0.1 in EVIDEM and 0.27 in ADVANCE), followed by the size of the population (0.09), the type of therapeutic benefit patient- level (0.09), population-level (0.08) and the efficacy (0.07) in EVIDEM. In ADVANCE, the combined unmet need/disease severity criteria were followed by the direct and meaningful endpoints (0.15), safety (0.12), contraindications (0.08), and indirect surrogate endpoints (0.07). This survey’s results were concordant with those reported in countries that have conducted similar surveys such as France, Italy and Spain. MCDA methodology could be used as a cornerstone to enhance evidence-based discussions among Lebanese stakeholders involved in decision-making processes.

Background The Japanese quail (Coturnix japonica) is a popular domestic poultry species and an increasingly significant model species in avian developmental, behavioural and disease research. Results We have produced a high-quality quail genome sequence, spanning 0.93 Gb assigned to 33 chromosomes. In terms of contiguity, assembly statistics, gene content and chromosomal organisation, the quail genome shows high similarity to the chicken genome. We demonstrate the utility of this genome through three diverse applications. First, we identify selection signatures and candidate genes associated with social behaviour in the quail genome, an important agricultural and domestication trait. Second, we investigate the effects and interaction of photoperiod and temperature on the transcriptome of the quail medial basal hypothalamus, revealing key mechanisms of photoperiodism. Finally, we investigate the response of quail to H5N1 influenza infection. In quail lung, many critical immune genes and pathways were downregulated after H5N1 infection, and this may be key to the susceptibility of quail to H5N1. Conclusions We have produced a high-quality genome of the quail which will facilitate further studies into diverse research questions using the quail as a model avian species.

It is well established that haematopoietic stem and progenitor cells (HSPCs) are generated from a transient subset of specialized endothelial cells termed haemogenic, present in the yolk sac, placenta and aorta, through an endothelial-to-haematopoietic transition (EHT). HSPC generation via EHT is thought to be restricted to the early stages of development. By using experimental embryology and genetic approaches in birds and mice, respectively, we document here the discovery of a bone marrow haemogenic endothelium in the late fetus/young adult. These cells are capable of de novo producing a cohort of HSPCs in situ that harbour a very specific molecular signature close to that of aortic endothelial cells undergoing EHT or their immediate progenies, i.e., recently emerged HSPCs. Taken together, our results reveal that HSPCs can be generated de novo past embryonic stages. Understanding the molecular events controlling this production will be critical for devising innovative therapies.

The Japanese quail ( Coturnix japonica ) is a popular domestic poultry species and an increasingly significant model species in avian developmental, behavioural and disease research. We have produced a high-quality quail genome sequence, spanning 0.93 Gb assigned to 33 chromosomes. In terms of contiguity, assembly statistics, gene content and chromosomal organization, the quail genome shows high similarity to the chicken genome. We demonstrate the utility of this genome through three diverse applications. First, we identify selection signatures and candidate genes associated with social behaviour in the quail genome, an important agricultural and domestication trait. Second, we investigate the effects and interaction of photoperiod and temperature on the transcriptome of the quail medial basal hypothalamus, revealing key mechanisms of photoperiodism. Finally, we investigate the response of quail to H5N1 influenza infection. In quail lung, many critical immune genes and pathways were downregulated, and this may be key to the susceptibility of quail to H5N1. This genome will facilitate further research into diverse research questions using the quail as a model avian species.

SUMMARY Cilia-driven movements of the cerebrospinal fluid (CSF) are involved in zebrafish axis straightness, both in embryos and juveniles [1, 2]. In embryos, axis straightness requires cilia-dependent assembly of the Reissner fiber (RF), a SCO-spondin polymer running down the brain and spinal cord CSF-filled cavities [3]. Reduced expression levels of the urp1 and urp2 genes encoding neuropeptides of the Urotensin II family in CSF-contacting neurons (CSF-cNs) also underlie embryonic ventral curvature of several cilia motility mutants [4]. Moreover, mutants for scospondin and uts2r3 (a Urotensin II peptide family receptor gene) develop scoliosis at juvenile stages [3, 4]. However, whether RF maintenance and URP signaling are perturbed in juvenile scoliotic ciliary mutants and how these perturbations are linked to scoliosis is unknown. Here we produced mutants in the zebrafish ortholog of the human RPGRIP1L ciliopathy gene encoding a transition zone protein [5–7]. rpgrip1l -/- zebrafish had normal embryogenesis and developed 3D spine torsions in juveniles. Cilia lining the CNS cavities were normal in rpgrip1l -/- embryos but sparse and malformed in juveniles and adults. Hindbrain ventricle dilations were present at scoliosis onset, suggesting defects in CSF flow. Immunostaining showed a secondary loss of RF correlating with juvenile scoliosis. Surprisingly, transcriptome analysis of rgprip1l mutants at scoliosis onset uncovered increased levels of urp1 and urp2 expression. Overexpressing urp2 in foxj1 -expressing cells triggered scoliosis in rpgrip1l heterozygotes. Thus, our results demonstrate that increased URP signaling drives scoliosis onset in a ciliopathy mutant. We propose that imbalanced levels of URP neuropeptides in CSF-cNs may be an initial trigger of scoliosis.

Introduction Well- or moderately differentiated gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are often slow-growing, and some patients with unresectable, asymptomatic, non-functioning tumors may face the choice between watchful waiting (WW), or somatostatin analogues (SSA) to delay progression. We developed a comprehensive multi-criteria decision analysis (MCDA) framework to help patients and physicians clarify their values and preferences, consider each decision criterion, and support communication and shared decision-making. Methods The framework was adapted from a generic MCDA framework (EVIDEM) with patient and clinician input. During a workshop, patients and clinicians expressed their individual values and preferences (criteria weights) and, on the basis of two scenarios (treatment vs WW; SSA-1 [lanreotide] vs SSA-2 [octreotide]) with evidence from a literature review, expressed how consideration of each criterion would impact their decision in favor of either option (score), and shared their knowledge and insights verbally and in writing. Results The framework included benefit-risk criteria and modulating factors, such as disease severity, quality of evidence, costs, and constraints. Overall and progression-free survival being most important, criteria weights ranged widely, highlighting variations in individual values and the need to share them. Scoring and considering each criterion prompted a rich exchange of perspectives and uncovered individual assumptions and interpretations. At the group level, type of benefit, disease severity, effectiveness, and quality of evidence favored treatment; cost aspects favored WW (scenario 1). For scenario 2, most criteria did not favor either option. Conclusions Patients and clinicians consider many aspects in decision-making. The MCDA framework provided a common interpretive frame to structure this complexity, support individual reflection, and share perspectives. Funding Ipsen Pharma.