24 research outputs found
The Outcome of Neutrophil-T Cell Contact Differs Depending on Activation Status of Both Cell Types
Neutrophils and T cells exist in close proximity in lymph nodes and inflamed tissues duringhealth and disease. They are able to form stable interactions, with profound effects on thephenotype and function of the T cells. However, the outcome of these effects arefrequently contradictory; in some systems neutrophils suppress T cell proliferation, inothers they are activatory or present antigen directly. Published protocols modelling theseinteractions in vitro do not reflect the full range of interactions found in vivo; they do notexamine how activated and naïve T cells differentially respond to neutrophils, or whetherde-granulating or resting neutrophils induce different outcomes. Here, we established aculture protocol to ask these questions with human T cells and autologous neutrophils.We find that resting neutrophils suppress T cell proliferation, activation and cytokineproduction but that de-granulating neutrophils do not, and neutrophil-releasedintracellular contents enhance proliferation. Strikingly, we also demonstrate that T cellsearly in the activation process are susceptible to suppression by neutrophils, while laterstage T cells are not, and naïve T cells do not respond at all. Our protocol therefore allowsnuanced analysis of the outcome of interaction of these cells and may explain thecontradictory results observed previously
Cell-Free DNA Screening: Complexities and Challenges of Clinical Implementation
Screening for fetal aneuploidy in pregnant women using cell-free DNA has increased dramatically since the technology became commercially available in 2011. Since that time, numerous trials have demonstrated high sensitivity and specificity to screen for common aneuploidies in high-risk populations. Studies assessing the performance of these tests in low-risk populations have also demonstrated improved detection rates compared with traditional, serum-based screening strategies. Concurrent with the increased use of this technology has been a decrease in invasive procedures (amniocentesis and chorionic villus sampling). As the technology becomes more widely understood, available, and utilized, challenges regarding its clinical implementation have become apparent. Some of these challenges include test failures, false-positive and false-negative results, limitations in positive predictive value in low-prevalence populations, and potential maternal health implications of abnormal results. In addition, commercial laboratories are expanding screening beyond common aneuploidies to include microdeletion screening and whole genome screening. This review article is intended to provide the practicing obstetrician with a summary of the complexities of cell-free DNA screening and the challenges of implementing it in the clinical setting
Requirement analysis for the DiSSCo research infrastructure
DiSSCo – the Distributed System of Scientific Collections – will mobilise, unify and deliver bio- and geo-diversity information at the scale, form and precision required by scientific communities, and thereby transform a fragmented landscape into a coherent and responsive research infrastructure. At present DiSSCo has 115 partners from 21 countries across Europe. The DiSSCo research infrastructure will enable critical new insights from integrated digital data to address some of the world's greatest challenges, such as biodiversity loss, food security and impacts of climate change. A requirement analysis for DiSSCo was conducted to ensure that all of its envisioned future uses are accommodated through a large survey using epic user stories. An epic user story has the following format: As [e.g. scientist] I want to [e.g. map the distribution of a species through time] so that I [e.g. analyse the impact of climate change] for this I need [e.g. all georeferenced specimens records through time] Several consultation rounds within the ICEDIG community resulted in 78 unique user stories that were assigned to one, or more, out of seven recognized stakeholder categories: - Research, - Collection management, - Technical support, - Policy, - Education, - Industry, and - External. Each user story was assessed for the level of collection detail it required; four levels of detail were recognised: Collection, Taxonomic, Storage unit, and Specimen level. Furthermore, it was assessed whether the future envisioned use of digitised natural history collections were possible without the DiSSCo research infrastructure. Subsequently 1243 identified stakeholders were invited to review the DiSSCo user stories through a Survey Monkey questionnaire. Additionally, an invitation for review was posted in several Facebook groups and announced on Twitter. A total of 379 stakeholders responded to the invitation, which led to 85 additional user stories for the envisioned use of the DiSSCo research infrastructure. In order to assess which component of the DiSSCo data flow diagram should facilitate the described user story, all user stories were mapped to the five phases of the DiSSCo Data Management Cycle (DMC), including data: - acquisition, - curation, - publishing, - processing, and - use. At present, the user stories are being analysed and the results will be presented in this symposium
Requirement analysis for the DiSSCo research infrastructure
DiSSCo – the Distributed System of Scientific Collections – will mobilise, unify and deliver bio- and geo-diversity information at the scale, form and precision required by scientific communities, and thereby transform a fragmented landscape into a coherent and responsive research infrastructure. At present DiSSCo has 115 partners from 21 countries across Europe. The DiSSCo research infrastructure will enable critical new insights from integrated digital data to address some of the world's greatest challenges, such as biodiversity loss, food security and impacts of climate change. A requirement analysis for DiSSCo was conducted to ensure that all of its envisioned future uses are accommodated through a large survey using epic user stories. An epic user story has the following format: As [e.g. scientist] I want to [e.g. map the distribution of a species through time] so that I [e.g. analyse the impact of climate change] for this I need [e.g. all georeferenced specimens records through time] Several consultation rounds within the ICEDIG community resulted in 78 unique user stories that were assigned to one, or more, out of seven recognized stakeholder categories: - Research, - Collection management, - Technical support, - Policy, - Education, - Industry, and - External. Each user story was assessed for the level of collection detail it required; four levels of detail were recognised: Collection, Taxonomic, Storage unit, and Specimen level. Furthermore, it was assessed whether the future envisioned use of digitised natural history collections were possible without the DiSSCo research infrastructure. Subsequently 1243 identified stakeholders were invited to review the DiSSCo user stories through a Survey Monkey questionnaire. Additionally, an invitation for review was posted in several Facebook groups and announced on Twitter. A total of 379 stakeholders responded to the invitation, which led to 85 additional user stories for the envisioned use of the DiSSCo research infrastructure. In order to assess which component of the DiSSCo data flow diagram should facilitate the described user story, all user stories were mapped to the five phases of the DiSSCo Data Management Cycle (DMC), including data: - acquisition, - curation, - publishing, - processing, and - use. At present, the user stories are being analysed and the results will be presented in this symposium
High purity isolation of low density neutrophils casts doubt on their exceptionality in health and disease
Low density neutrophils (LDNs) are described in a number of inflammatory conditions, cancers and infections and associated with immunopathology, and a mechanistic role in disease. The role of LDNs at homeostasis in healthy individuals has not been investigated. We have developed an isolation protocol that generates high purity LDNs from healthy donors. Healthy LDNs were identical to healthy normal density neutrophils (NDNs), aside from reduced neutrophil extracellular trap formation. CD66b, CD16, CD15, CD10, CD54, CD62L, CXCR2, CD47 and CD11b were expressed at equivalent levels in healthy LDNs and NDNs and underwent apoptosis and ROS production interchangeably. Healthy LDNs had no differential effect on CD4(+) or CD8(+) T cell proliferation or IFNγ production compared with NDNs. LDNs were generated from healthy NDNs in vitro by activation with TNF, LPS or fMLF, suggesting a mechanism of LDN generation in disease however, we show neutrophilia in people with Cystic Fibrosis (CF) was not due to increased LDNs. LDNs are present in the neutrophil pool at homeostasis and have limited functional differences to NDNs. We conclude that increased LDN numbers in disease reflect the specific pathology or inflammatory environment and that neutrophil density alone is inadequate to classify discrete functional populations of neutrophils
Holoprosencephaly–polydactyly/pseudotrisomy 13: a presentation of two new cases and a review of the literature
Patients with a combination of holoprosencephaly and polydactyly, but with apparently normal chromosomes, may be clinically diagnosed with holoprosencephaly–polydactyly syndrome (HPS), also termed pseudotrisomy 13. However, the criteria for HPS have been controversial since the advent of the diagnostic term, and a clear understanding of the condition lacks definitive delineation. We review the historical and current perspectives on the condition and analyze findings in 40 patients with apparent HPS, including cases from the literature and two previously unreported patients. Overall, our analysis suggests previously unrecognized trends in patients diagnosed with HPS. Specifically, there appears to be a higher prevalence of visceral anomalies, most significantly cardiac and genitourinary, but also with increased gastrointestinal, pulmonary, adrenal, skeletal, and renal abnormalities, in patients with HPS. Although these visceral anomalies may not be essential for the identification of HPS, clinicians should be aware of the presence of such characteristics in these patients to optimize management and help establish etiologies
The neutrophil antimicrobial peptide cathelicidin promotes Th17 differentiation
The host defence peptide cathelicidin (LL-37 in humans, mCRAMP in mice) is released from neutrophils by de-granulation, NETosis and necrotic death; it has potent anti-pathogen activity as well as being a broad immunomodulator. Here we report that cathelicidin is a powerful Th17 potentiator which enhances aryl hydrocarbon receptor (AHR) and RORγt expression, in a TGF-β1-dependent manner. In the presence of TGF-β1, cathelicidin enhanced SMAD2/3 and STAT3 phosphorylation, and profoundly suppressed IL-2 and T-bet, directing T cells away from Th1 and into a Th17 phenotype. Strikingly, Th17 but not Th1 cells were protected from apoptosis by cathelicidin. We show that cathelicidin is released by neutrophils in mouse lymph nodes and that cathelicidin-deficient mice display suppressed Th17 responses during inflammation, but not at steady state. We propose that the neutrophil cathelicidin is required for maximal Th17 differentiation, and that this is one method by which early neutrophilia directs subsequent adaptive immune responses
The senescent secretome drives PLVAP expression in cultured human hepatic endothelia to promote monocyte transmigration
Liver sinusoidal endothelial cells (LSEC) undergo significant phenotypic change in chronic liver disease (CLD), and yet the factors that drive this process and the impact on their function as a vascular barrier and gatekeeper for immune cell recruitment are poorly understood. Plasmalemma-vesicle-associated protein (PLVAP) has been characterized as a marker of LSEC in CLD; notably we found that PLVAP upregulation strongly correlated with markers of tissue senescence. Furthermore, exposure of human LSEC to the senescence-associated secretory phenotype (SASP) led to a significant upregulation of PLVAP. Flow-based assays demonstrated that SASP-driven leukocyte recruitment was characterized by paracellular transmigration of monocytes while the majority of lymphocytes migrated transcellularly. Knockdown studies confirmed that PLVAP selectively supported monocyte transmigration mediated through PLVAP's impact on LSEC permeability by regulating phospho-VE-cadherin expression and endothelial gap formation. PLVAP may therefore represent an endothelial target that selectively shapes the senescence-mediated immune microenvironment in liver disease. [Abstract copyright: © 2023 The Author(s).
Prenatal exome sequencing in anomalous fetuses: new opportunities and challenges
We investigated the diagnostic and clinical performance of exome sequencing (ES) in fetuses with sonographic abnormalities with normal karyotype, microarray and, in some cases, normal gene specific sequencing
An Inhaled Galectin-3 Inhibitor in COVID-19 Pneumonitis (DEFINE):A Phase Ib/IIa Randomised Controlled Trial
RATIONALE: High circulating galectin-3 is associated with poor outcomes in patients with coronavirus disease (COVID-19). We hypothesized that GB0139, a potent inhaled thiodigalactoside galectin-3 inhibitor with antiinflammatory and antifibrotic actions, would be safely and effectively delivered in COVID-19 pneumonitis. OBJECTIVES: Primary outcomes were safety and tolerability of inhaled GB0139 as an add-on therapy for patients hospitalized with COVID-19 pneumonitis. METHODS: We present the findings of two arms of a phase Ib/IIa randomized controlled platform trial in hospitalized patients with confirmed COVID-19 pneumonitis. Patients received standard of care (SoC) or SoC plus 10 mg inhaled GB0139 twice daily for 48 hours, then once daily for up to 14 days or discharge. MEASUREMENTS AND MAIN RESULTS: Data are reported from 41 patients, 20 of which were assigned randomly to receive GB0139. Primary outcomes: the GB0139 group experienced no treatment-related serious adverse events. Incidences of adverse events were similar between treatment arms (40 with GB0139 + SoC vs. 35 with SoC). Secondary outcomes: plasma GB0139 was measurable in all patients after inhaled exposure and demonstrated target engagement with decreased circulating galectin (overall treatment effect post-hoc analysis of covariance [ANCOVA] over days 2–7; P = 0.0099 vs. SoC). Plasma biomarkers associated with inflammation, fibrosis, coagulopathy, and major organ function were evaluated. CONCLUSIONS: In COVID-19 pneumonitis, inhaled GB0139 was well-tolerated and achieved clinically relevant plasma concentrations with target engagement. The data support larger clinical trials to determine clinical efficacy. Clinical trial registered with ClinicalTrials.gov (NCT04473053) and EudraCT (2020–002230–32)