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3.
ACS Cent Sci ; 9(3): 393-404, 2023 Mar 22.
Article in English | MEDLINE | ID: covidwho-2261001

ABSTRACT

The emergence of a polybasic cleavage motif for the protease furin in SARS-CoV-2 spike has been established as a major factor for human viral transmission. The region N-terminal to that motif is extensively mutated in variants of concern (VOCs). Besides furin, spikes from these variants appear to rely on other proteases for maturation, including TMPRSS2. Glycans near the cleavage site have raised questions about proteolytic processing and the consequences of variant-borne mutations. Here, we identify that sialic acid-containing O-linked glycans on Thr678 of SARS-CoV-2 spike influence furin and TMPRSS2 cleavage and posit O-linked glycosylation as a likely driving force for the emergence of VOC mutations. We provide direct evidence that the glycosyltransferase GalNAc-T1 primes glycosylation at Thr678 in the living cell, an event that is suppressed by mutations in the VOCs Alpha, Delta, and Omicron. We found that the sole incorporation of N-acetylgalactosamine did not impact furin activity in synthetic O-glycopeptides, but the presence of sialic acid reduced the furin rate by up to 65%. Similarly, O-glycosylation with a sialylated trisaccharide had a negative impact on TMPRSS2 cleavage. With a chemistry-centered approach, we substantiate O-glycosylation as a major determinant of spike maturation and propose disruption of O-glycosylation as a substantial driving force for VOC evolution.

4.
PLoS One ; 18(2): e0272472, 2023.
Article in English | MEDLINE | ID: covidwho-2240758

ABSTRACT

INTRODUCTION: Long COVID (LC), the persistent symptoms ≥12 weeks following acute COVID-19, presents major threats to individual and public health across countries, affecting over 1.5 million people in the UK alone. Evidence-based interventions are urgently required and an integrated care pathway approach in pragmatic trials, which include investigations, treatments and rehabilitation for LC, could provide scalable and generalisable solutions at pace. METHODS AND ANALYSIS: This is a pragmatic, multi-centre, cluster-randomised clinical trial of two components of an integrated care pathway (Coverscan™, a multi-organ MRI, and Living with COVID Recovery™, a digitally enabled rehabilitation platform) with a nested, Phase III, open label, platform randomised drug trial in individuals with LC. Cluster randomisation is at level of primary care networks so that integrated care pathway interventions are delivered as "standard of care" in that area. The drug trial randomisation is at individual level and initial arms are rivaroxaban, colchicine, famotidine/loratadine, compared with no drugs, with potential to add in further drug arms. The trial is being carried out in 6-10 LC clinics in the UK and is evaluating the effectiveness of a pathway of care for adults with LC in reducing fatigue and other physical, psychological and functional outcomes at 3 months. The trial also includes an economic evaluation which will be described separately. ETHICS AND DISSEMINATION: The protocol was reviewed by South Central-Berkshire Research Ethics Committee (reference: 21/SC/0416). All participating sites obtained local approvals prior to recruitment. Coverscan™ has UK certification (UKCA 752965). All participants will provide written consent to take part in the trial. The first participant was recruited in July 2022 and interim/final results will be disseminated in 2023, in a plan co-developed with public and patient representatives. The results will be presented at national and international conferences, published in peer reviewed medical journals, and shared via media (mainstream and social) and patient support organisations. TRIAL REGISTRATION NUMBER: ISRCTN10665760.


Subject(s)
COVID-19 , Delivery of Health Care, Integrated , Adult , Humans , SARS-CoV-2 , Post-Acute COVID-19 Syndrome , Treatment Outcome , Randomized Controlled Trials as Topic , Multicenter Studies as Topic , Clinical Trials, Phase III as Topic
6.
Cell Rep Med ; 3(10): 100781, 2022 10 18.
Article in English | MEDLINE | ID: covidwho-2042207

ABSTRACT

Patients with blood cancer continue to have a greater risk of inadequate immune responses following three COVID-19 vaccine doses and risk of severe COVID-19 disease. In the context of the CAPTURE study (NCT03226886), we report immune responses in 80 patients with blood cancer who received a fourth dose of BNT162b2. We measured neutralizing antibody titers (NAbTs) using a live virus microneutralization assay against wild-type (WT), Delta, and Omicron BA.1 and BA.2 and T cell responses against WT and Omicron BA.1 using an activation-induced marker (AIM) assay. The proportion of patients with detectable NAb titers and T cell responses after the fourth vaccine dose increased compared with that after the third vaccine dose. Patients who received B cell-depleting therapies within the 12 months before vaccination have the greatest risk of not having detectable NAbT. In addition, we report immune responses in 57 patients with breakthrough infections after vaccination.


Subject(s)
COVID-19 Vaccines , COVID-19 , Neoplasms , Humans , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , Clinical Studies as Topic , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Immunity , SARS-CoV-2
9.
Cancer Cell ; 40(2): 114-116, 2022 02 14.
Article in English | MEDLINE | ID: covidwho-1588171
10.
Nat Cancer ; 2: 1321-1337, 2021 12.
Article in English | MEDLINE | ID: covidwho-1510627

ABSTRACT

CAPTURE (NCT03226886) is a prospective cohort study of COVID-19 immunity in patients with cancer. Here we evaluated 585 patients following administration of two doses of BNT162b2 or AZD1222 vaccines, administered 12 weeks apart. Seroconversion rates after two doses were 85% and 59% in patients with solid and hematological malignancies, respectively. A lower proportion of patients had detectable neutralizing antibody titers (NAbT) against SARS-CoV-2 variants of concern (VOCs) vs wildtype (WT). Patients with hematological malignancies were more likely to have undetectable NAbT and had lower median NAbT vs solid cancers against both WT and VOCs. In comparison with individuals without cancer, patients with haematological, but not solid, malignancies had reduced NAb responses. Seroconversion showed poor concordance with NAbT against VOCs. Prior SARS-CoV-2 infection boosted NAb response including against VOCs, and anti-CD20 treatment was associated with undetectable NAbT. Vaccine-induced T-cell responses were detected in 80% of patients, and were comparable between vaccines or cancer types. Our results have implications for the management of cancer patients during the ongoing COVID-19 pandemic.


Subject(s)
Adaptive Immunity/immunology , Antibodies, Neutralizing/immunology , COVID-19 Vaccines/immunology , COVID-19/immunology , Carcinoma, Renal Cell/complications , Kidney Neoplasms/complications , SARS-CoV-2/immunology , Adult , Aged , Aged, 80 and over , BNT162 Vaccine/administration & dosage , BNT162 Vaccine/immunology , COVID-19/complications , COVID-19/epidemiology , COVID-19 Vaccines/administration & dosage , ChAdOx1 nCoV-19/administration & dosage , ChAdOx1 nCoV-19/immunology , Female , Humans , Immunogenicity, Vaccine/immunology , Longitudinal Studies , Male , Middle Aged , Pandemics/prevention & control , Prospective Studies , SARS-CoV-2/genetics , SARS-CoV-2/physiology , T-Lymphocytes/immunology , T-Lymphocytes/virology , Vaccination/methods
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