Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
1.
Diabetes Ther ; 14(6): 977-988, 2023 Jun.
Article in English | MEDLINE | ID: covidwho-20236668

ABSTRACT

INTRODUCTION: Effective and scalable solutions to support management of Type 2 Diabetes (T2D) at a distance are a priority for health systems worldwide. The use of personalised care planning has been shown to be effective at improving the health outcomes and the experience of care amongst people with T2D and other long-term health conditions. Here we describe a specific example of such an intervention. METHODS: The sample comprised 197 participants with T2D randomised to either the active intervention group with digital health planning (App + usual care), with 115 participants, or the control group (usual care), with 82 participants. We analysed data in relation to changes in body mass index (BMI) and glycated haemoglobin (HbA1c) over a 6-month follow-up period. We also analysed responses to questionnaires sent out and held interviews with participants that were in the active treatment group and therefore had a care plan created and access to an app. RESULTS: The active treatment group had significant reductions in HbA1c (p < 0.01) and BMI (p < 0.037) vs the control group (no significant change). The average percentage change in HbA1c for the treatment group over 6 months was - 7.4% (± SE 1.4%), compared with 1.8% (± SE 2.1%) for the control group. The average percentage change in BMI for the treatment group was - 0.7% (± SE 0.4%) and it was - 0.2% (± SE 0.5%) for the control group. A higher percentage of the active treatment group reduced their HbA1c and BMI than the control group. For HbA1c, 72.4% of the active treatment group reduced their HbA1c, compared to 41.5% of the control group. For BMI, 52.7% of the active treatment group experienced a reduction, compared to 42.9% for the control group. Self-measured quality of life (QoL) improved for patients in the active treatment group, shown by an increase in their pre-trial to post-trial EQ-5D-5L rating by an average of 0.0464 (± SE 0.0625), compared to a decrease of 0.0086 (± SE 0.0530) for the control group. The average EQ VAS score also increased pre- to post-trial for the active treatment group, on average by 8.2%, whereas it decreased by an  average of - 2.8% for the control group. CONCLUSION: These findings point to how the provision of personalised plans of care, support and education linked to a mobile app, can result in HbA1c and BMI reduction for many individuals with T2D. The use of a patient management app as well as a personalised care plan also led to an improvement in patient self-rated QoL and engagement.

2.
BMC Bioinformatics ; 23(1): 547, 2022 Dec 19.
Article in English | MEDLINE | ID: covidwho-2196036

ABSTRACT

As of June 2022, the GISAID database contains more than 11 million SARS-CoV-2 genomes, including several thousand nucleotide sequences for the most common variants such as delta or omicron. These SARS-CoV-2 strains have been collected from patients around the world since the beginning of the pandemic. We start by assessing the similarity of all pairs of nucleotide sequences using the Jaccard index and principal component analysis. As shown previously in the literature, an unsupervised cluster analysis applied to the SARS-CoV-2 genomes results in clusters of sequences according to certain characteristics such as their strain or their clade. Importantly, we observe that nucleotide sequences of common variants are often outliers in clusters of sequences stemming from variants identified earlier on during the pandemic. Motivated by this finding, we are interested in applying outlier detection to nucleotide sequences. We demonstrate that nucleotide sequences of common variants (such as alpha, delta, or omicron) can be identified solely based on a statistical outlier criterion. We argue that outlier detection might be a useful surveillance tool to identify emerging variants in real time as the pandemic progresses.


Subject(s)
COVID-19 , Humans , Base Sequence , SARS-CoV-2 , Cluster Analysis , Databases, Factual
4.
J Exp Med ; 219(9)2022 09 05.
Article in English | MEDLINE | ID: covidwho-1984992

ABSTRACT

Humoral immunity to SARS-CoV-2 can be supplemented with polyclonal sera from convalescent donors or an engineered monoclonal antibody (mAb) product. While pentameric IgM antibodies are responsible for much of convalescent sera's neutralizing capacity, all available mAbs are based on the monomeric IgG antibody subtype. We now show that IgM mAbs derived from immune memory B cell receptors are potent neutralizers of SARS-CoV-2. IgM mAbs outperformed clonally identical IgG antibodies across a range of affinities and SARS-CoV-2 receptor-binding domain epitopes. Strikingly, efficacy against SARS-CoV-2 viral variants was retained for IgM but not for clonally identical IgG. To investigate the biological role for IgM memory in SARS-CoV-2, we also generated IgM mAbs from antigen-experienced IgM+ memory B cells in convalescent donors, identifying a potent neutralizing antibody. Our results highlight the therapeutic potential of IgM mAbs and inform our understanding of the role for IgM memory against a rapidly mutating pathogen.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Monoclonal , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/therapy , Humans , Immunization, Passive , Immunoglobulin G , Immunoglobulin M , Memory B Cells , Spike Glycoprotein, Coronavirus , COVID-19 Serotherapy
5.
Nature ; 606(7914): 576-584, 2022 06.
Article in English | MEDLINE | ID: covidwho-1921629

ABSTRACT

SARS-CoV-2 can cause acute respiratory distress and death in some patients1. Although severe COVID-19 is linked to substantial inflammation, how SARS-CoV-2 triggers inflammation is not clear2. Monocytes and macrophages are sentinel cells that sense invasive infection to form inflammasomes that activate caspase-1 and gasdermin D, leading to inflammatory death (pyroptosis) and the release of potent inflammatory mediators3. Here we show that about 6% of blood monocytes of patients with COVID-19 are infected with SARS-CoV-2. Monocyte infection depends on the uptake of antibody-opsonized virus by Fcγ receptors. The plasma of vaccine recipients does not promote antibody-dependent monocyte infection. SARS-CoV-2 begins to replicate in monocytes, but infection is aborted, and infectious virus is not detected in the supernatants of cultures of infected monocytes. Instead, infected cells undergo pyroptosis mediated by activation of NLRP3 and AIM2 inflammasomes, caspase-1 and gasdermin D. Moreover, tissue-resident macrophages, but not infected epithelial and endothelial cells, from lung autopsies from patients with COVID-19 have activated inflammasomes. Taken together, these findings suggest that antibody-mediated SARS-CoV-2 uptake by monocytes and macrophages triggers inflammatory cell death that aborts the production of infectious virus but causes systemic inflammation that contributes to COVID-19 pathogenesis.


Subject(s)
COVID-19 , Inflammation , Monocytes , Receptors, IgG , SARS-CoV-2 , COVID-19/virology , Caspase 1/metabolism , DNA-Binding Proteins , Humans , Inflammasomes/metabolism , Inflammation/metabolism , Inflammation/virology , Monocytes/metabolism , Monocytes/virology , NLR Family, Pyrin Domain-Containing 3 Protein , Phosphate-Binding Proteins , Pore Forming Cytotoxic Proteins , Receptors, IgG/metabolism
8.
Microbiol Spectr ; 10(2): e0021122, 2022 04 27.
Article in English | MEDLINE | ID: covidwho-1752769

ABSTRACT

The use of anti-spike (S) serologic assays as surrogate measurements of SARS-CoV-2 vaccine induced immunity will be an important clinical and epidemiological tool. The characteristics of a commercially available anti-S antibody assay (Roche Elecsys anti-SARS-CoV-2 S) were evaluated in a cohort of vaccine recipients. Levels were correlated with pseudotype neutralizing antibodies (NAb) across SARS-CoV-2 variants. We recruited adults receiving a two-dose series of mRNA-1273 or BNT162b2 and collected serum at scheduled intervals up to 8 months post-first vaccination. Anti-S and NAb levels were measured, and correlation was evaluated by (i) vaccine type and (ii) SARS-CoV-2 variant (wild-type, Alpha, Beta, Gamma, and three constructs Day 146*, Day 152*, and RBM-2). Forty-six mRNA vaccine recipients were enrolled. mRNA-1273 vaccine recipients had higher peak anti-S and NAb levels compared with BNT162b2 (P < 0.001 for anti-S levels; P < 0.05 for NAb levels). When anti-S and NAb levels were compared, there was good correlation (all r values ≥ 0.85) in both BNT162b2 and mRNA-1273 vaccine recipients across all evaluated variants; however, these correlations were nonlinear in nature. Lower correlation was identified between anti-S and NAb for the Beta variant (r = 0.88) compared with the wild-type (WT) strain (r = 0.94). Finally, the degree of neutralizing activity at any given anti-S level was lower for each variant compared with that of the WT strain, (P < 0.001). Although the Roche anti-S assay correlates well with NAb levels, this association is affected by vaccine type and SARS-CoV-2 variant. These variables must be considered when interpreting anti-S levels. IMPORTANCE We evaluated anti-spike antibody concentrations in healthy mRNA vaccinated individuals and compared these concentrations to values obtained from pseudotype neutralization assays targeting SARS-CoV-2 variants of concern to determine how well anti-spike antibodies correlate with neutralizing titers, which have been used as a marker of immunity from COVID-19 infection. We found high peak anti-spike concentrations in these individuals, with significantly higher levels seen in mRNA-1273 vaccine recipients. When we compared anti-spike and pseudotype neuralization titers, we identified good correlation; however, this correlation was affected by both vaccine type and variant, illustrating the difficulty of applying a "one size fits all" approach to anti-spike result interpretation. Our results support CDC recommendations to discourage anti-spike antibody testing to assess for immunity after vaccination and cautions providers in their interpretations of these results as a surrogate of protection in COVID-vaccinated individuals.


Subject(s)
COVID-19 , SARS-CoV-2 , 2019-nCoV Vaccine mRNA-1273 , Adult , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19/diagnosis , COVID-19/prevention & control , COVID-19 Vaccines , Humans , SARS-CoV-2/genetics , Vaccines, Synthetic , mRNA Vaccines
9.
Science ; 375(6578): eabl6251, 2022 01 21.
Article in English | MEDLINE | ID: covidwho-1650842

ABSTRACT

Many studies have examined the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants on neutralizing antibody activity after they have become dominant strains. Here, we evaluate the consequences of further viral evolution. We demonstrate mechanisms through which the SARS-CoV-2 receptor binding domain (RBD) can tolerate large numbers of simultaneous antibody escape mutations and show that pseudotypes containing up to seven mutations, as opposed to the one to three found in previously studied variants of concern, are more resistant to neutralization by therapeutic antibodies and serum from vaccine recipients. We identify an antibody that binds the RBD core to neutralize pseudotypes for all tested variants but show that the RBD can acquire an N-linked glycan to escape neutralization. Our findings portend continued emergence of escape variants as SARS-CoV-2 adapts to humans.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Immune Evasion , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/metabolism , BNT162 Vaccine/immunology , Betacoronavirus/immunology , COVID-19/immunology , COVID-19/virology , Cross Reactions , Cryoelectron Microscopy , Crystallography, X-Ray , Epitopes , Evolution, Molecular , Humans , Models, Molecular , Mutation , Polysaccharides/analysis , Protein Binding , Protein Domains , Receptors, Coronavirus/chemistry , Receptors, Coronavirus/metabolism , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Viral Pseudotyping
10.
Nat Chem Biol ; 17(10): 1057-1064, 2021 10.
Article in English | MEDLINE | ID: covidwho-1281726

ABSTRACT

The predominant approach for antibody generation remains animal immunization, which can yield exceptionally selective and potent antibody clones owing to the powerful evolutionary process of somatic hypermutation. However, animal immunization is inherently slow, not always accessible and poorly compatible with many antigens. Here, we describe 'autonomous hypermutation yeast surface display' (AHEAD), a synthetic recombinant antibody generation technology that imitates somatic hypermutation inside engineered yeast. By encoding antibody fragments on an error-prone orthogonal DNA replication system, surface-displayed antibody repertoires continuously mutate through simple cycles of yeast culturing and enrichment for antigen binding to produce high-affinity clones in as little as two weeks. We applied AHEAD to generate potent nanobodies against the SARS-CoV-2 S glycoprotein, a G-protein-coupled receptor and other targets, offering a template for streamlined antibody generation at large.


Subject(s)
Antibody Formation/immunology , Protein Engineering/methods , Recombinant Proteins/biosynthesis , Antibodies/immunology , Antigens , COVID-19/immunology , Humans , Peptide Library , Recombinant Proteins/metabolism , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Saccharomyces cerevisiae/metabolism , Single-Domain Antibodies/genetics , Single-Domain Antibodies/metabolism , Spike Glycoprotein, Coronavirus/immunology
11.
Mol Cell ; 81(11): 2261-2265, 2021 06 03.
Article in English | MEDLINE | ID: covidwho-1246090

ABSTRACT

COVID-19 altered our lives and pushed scientific research to operate at breakneck speed, leading to significant breakthroughs in record time. We asked experts in the field about the challenges they faced in transitioning, rapidly but safely, to working on the virus while navigating the shutdown. Their voices converge on the importance of teamwork, forging new collaborations, and working toward a shared goal.


Subject(s)
Biomedical Research , COVID-19/epidemiology , COVID-19/prevention & control , Pandemics , Quarantine , SARS-CoV-2 , Humans , Poetry as Topic
12.
Cell ; 184(10): 2605-2617.e18, 2021 05 13.
Article in English | MEDLINE | ID: covidwho-1135275

ABSTRACT

Many individuals mount nearly identical antibody responses to SARS-CoV-2. To gain insight into how the viral spike (S) protein receptor-binding domain (RBD) might evolve in response to common antibody responses, we studied mutations occurring during virus evolution in a persistently infected immunocompromised individual. We use antibody Fab/RBD structures to predict, and pseudotypes to confirm, that mutations found in late-stage evolved S variants confer resistance to a common class of SARS-CoV-2 neutralizing antibodies we isolated from a healthy COVID-19 convalescent donor. Resistance extends to the polyclonal serum immunoglobulins of four out of four healthy convalescent donors we tested and to monoclonal antibodies in clinical use. We further show that affinity maturation is unimportant for wild-type virus neutralization but is critical to neutralization breadth. Because the mutations we studied foreshadowed emerging variants that are now circulating across the globe, our results have implications to the long-term efficacy of S-directed countermeasures.


Subject(s)
Antibodies, Viral/immunology , COVID-19 , Evolution, Molecular , Immune Evasion/immunology , Immunocompromised Host , Immunoglobulin Fab Fragments/immunology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Antibodies, Neutralizing , COVID-19/genetics , COVID-19/immunology , Female , HEK293 Cells , Humans , Male , Protein Domains , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology
SELECTION OF CITATIONS
SEARCH DETAIL