Although alterations in myeloid cells have been observed in COVID-19, the specific underlying mechanisms are not completely understood. Here, we examine the function of classical CD14+ monocytes in patients with mild and moderate COVID-19 during the acute phase of infection and in healthy individuals. Monocytes from COVID-19 patients display altered expression of cell surface receptors and a dysfunctional metabolic profile that distinguish them from healthy monocytes. Secondary pathogen sensing ex vivo leads to defects in pro-inflammatory cytokine and type-I IFN production in moderate COVID-19 cases, together with defects in glycolysis. COVID-19 monocytes switch their gene expression profile from canonical innate immune to pro-thrombotic signatures and are functionally pro-thrombotic, both at baseline and following ex vivo stimulation with SARS-CoV-2. Transcriptionally, COVID-19 monocytes are characterized by enrichment of pathways involved in hemostasis, immunothrombosis, platelet aggregation and other accessory pathways to platelet activation and clot formation. These results identify a potential mechanism by which monocyte dysfunction may contribute to COVID-19 pathology.
Immune thrombocytopenia (ITP) is traditionally considered an antibody-mediated disease. However, a number of features suggest alternative mechanisms of platelet destruction. In this study, we use a multi-dimensional approach to explore the role of cytotoxic CD8+ T cells in ITP. We characterised patients with ITP and compared them to age-matched controls using immunophenotyping, next-generation sequencing of T cell receptor (TCR) genes, single-cell RNA sequencing, and functional T cell and platelet assays. We found that adults with chronic ITP have increased polyfunctional, terminally differentiated effector memory CD8+ T cells (CD45RA+CD62L-) expressing intracellular interferon-g, tumour necrosis factor-a, and Granzyme B defining them as TEMRA cells. These TEMRA cells expand when the platelet count falls and show no evidence of physiological exhaustion. Deep sequencing of the T cell receptor showed expanded T cell clones in patients with ITP. T cell clones persisted over many years, were more prominent in patients with refractory disease, and expanded when the platelet count was low. Combined single-cell RNA and TCR sequencing of CD8+ T cells confirmed that the expanded clones are TEMRA cells. Using in vitro model systems, we show that CD8+ T cells from patients with ITP form aggregates with autologous platelets, release interferon-g and trigger platelet activation and apoptosis through TCR-mediated release of cytotoxic granules. These findings of clonally expanded CD8+ T cells causing platelet activation and apoptosis provide an antibody-independent mechanism of platelet destruction, indicating that targeting specific T-cell clones could be a novel therapeutic approach for patients with refractory ITP.
The 2015 Varsity Medical Ethics debate convened upon the motion: “This house believes nootropic drugs should be available under prescription”. This annual debate between students from the Universities of Oxford and Cambridge, now in its seventh year, provided the starting point for arguments on the subject. The present article brings together and extends many of the arguments put forward during the debate. We explore the current usage of nootropic drugs, their safety and whether it would be beneficial to individuals and society as a whole for them to be available under prescription. The Varsity Medical Debate was first held in 2008 with the aim of allowing students to engage in discussion about ethics and policy within healthcare. The event is held annually and it is hoped that this will allow future leaders to voice a perspective on the arguments behind topics that will feature heavily in future healthcare and science policy. This year the Oxford University Medical Society at the Oxford Union hosted the debate.
Every day in hospitals around the world, millions of interspecialty referrals are made to obtain advice on the optimal care and management of patients. In the UK, the brunt of this work is undertaken by junior doctors with less clinical experience than the specialist colleagues to which they refer. A survey of 283 junior doctors revealed that colleagues were underconfident when making referrals and struggled to know which specialty to contact, how to reach the specialty and what clinical information to include in the referral. More concerningly, 10% of those surveyed had experienced bullying or belittling behaviours and verbal aggression from colleagues when referring.The aim of this project was to design and implement a referrals toolkit for junior doctors to improve confidence making referrals and time to interspecialty advice, to improve patient care. Process mapping to understand the constituents of good referrals was combined with a failure modes and effects analysis describing how referrals fail to identify areas for intervention.A specialty referrals guide with all specialty contact information was created at the trust, demonstrating an increase in junior doctor median confidence from 3/5 (n=20) to 5/5 (n=23) (p<0.001); 65% found it quicker to refer with the guide and 81% found an improved time to discharge. A referrals cheat sheet was also created, containing specialty-specific information to be included when making a referral. This has been downloaded over 23 000 times from around the globe. Of survey respondents (n=43), 74% noted improved confidence in making referrals, 26% noted faster time to specialty advice and 19% found a positive impact on patient discharges. Overall, the referrals toolkit has been beneficial for both junior doctors and the patients for which they care and has been accessed by over 50% of new foundation doctors in 2021 and 2022.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.