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1.
J Med Virol ; 2022 Jul 21.
Article in English | MEDLINE | ID: covidwho-1941184

ABSTRACT

This study assessed T-cell responses in individuals with and without a positive antibody response to SARS-CoV-2, in symptomatic and asymptomatic individuals during the COVID-19 pandemic. Participants were drawn from the TwinsUK cohort, grouped by (a) presence or absence of COVID-associated symptoms (S+, S-), logged prospectively through the COVID Symptom Study app, and (b) anti-IgG Spike and anti-IgG Nucleocapsid antibodies measured by ELISA (Ab+, Ab-), during the first wave of the UK pandemic. T-cell helper and regulatory responses after stimulation with SARS-CoV-2 peptides were assessed. Thirty-two participants were included in the final analysis. Fourteen of 15 with IgG Spike antibodies had a T-cell response to SARS-CoV-2-specific peptides; none of 17 participants without IgG Spike antibodies had a T-cell response (χ2 : 28.2, p < 0.001). Quantitative T-cell responses correlated strongly with fold-change in IgG Spike antibody titer (ρ = 0.79, p < 0.0001) but not to symptom score (ρ = 0.17, p = 0.35). Humoral and cellular immune responses to SARS-CoV-2 are highly correlated. We found no evidence of cellular immunity suggestive of SARS-CoV2 infection in individuals with a COVID-19-like illness but negative antibodies.

2.
Viral Immunol ; 35(6): 425-436, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1937640

ABSTRACT

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory coronavirus 2 (SARS-CoV-2), has resulted in major worldwide disruption and loss of life over the last 2 years. Many research studies have shown waning serological SARS-CoV-2-specific IgG antibody titers over time, yet, it is unclear whether these changes are reflected in the potential functional reactivation of SARS-CoV-2 antigen-specific memory B cells (MBC) populations. This is especially true in the contexts of differing COVID-19 disease severity and after vaccination regimens. This study aimed to investigate these by polyclonal in vitro reactivation of MBC populations followed by analysis using SAR-CoV-2 antigen-specific B cell ELISpots and IgG antibody ELISAs. Natural disease-associated differences were investigated in 52 donors who have recovered from COVID-19 with varying disease severity, from asymptomatic to severe COVID-19 disease, accompanied by a longitudinal evaluation in a subset of donors. Overall, these data showed limited disease severity-associated differences between donor groups but did show that COVID-19 serologically positive donors had strong antigen-specific MBC-associated responses. MBC responses were better maintained 6 months after recovery from infection when compared to serological antigen-specific IgG antibody titers. A similar investigation after vaccination using 14 donors showed robust serological antigen-specific antibody responses against spike protein that waned over time. MBC-associated responses against spike protein were also observed but showed less waning over time, indicating maintenance of a protective response 6 months after vaccination. Further research is required to evaluate these putatively functional SARS-CoV-2-specific responses in the context of long-term protection mediated by vaccination against this pathogen.


Subject(s)
COVID-19 , Spike Glycoprotein, Coronavirus , Antibodies, Viral , COVID-19/prevention & control , Humans , Immunoglobulin G , Memory B Cells , SARS-CoV-2 , Vaccination
3.
Nat Commun ; 13(1): 3528, 2022 06 28.
Article in English | MEDLINE | ID: covidwho-1908168

ABSTRACT

The frequency of, and risk factors for, long COVID are unclear among community-based individuals with a history of COVID-19. To elucidate the burden and possible causes of long COVID in the community, we coordinated analyses of survey data from 6907 individuals with self-reported COVID-19 from 10 UK longitudinal study (LS) samples and 1.1 million individuals with COVID-19 diagnostic codes in electronic healthcare records (EHR) collected by spring 2021. Proportions of presumed COVID-19 cases in LS reporting any symptoms for 12+ weeks ranged from 7.8% and 17% (with 1.2 to 4.8% reporting debilitating symptoms). Increasing age, female sex, white ethnicity, poor pre-pandemic general and mental health, overweight/obesity, and asthma were associated with prolonged symptoms in both LS and EHR data, but findings for other factors, such as cardio-metabolic parameters, were inconclusive.


Subject(s)
COVID-19 , Electronic Health Records , COVID-19/complications , COVID-19/epidemiology , Female , Humans , Longitudinal Studies , Risk Factors , Surveys and Questionnaires , United Kingdom/epidemiology
4.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-337649

ABSTRACT

Over the course of the pandemic variants have arisen at a steady rate. The most recent variants to emerge, BA.4 and BA.5, form part of the Omicron lineage and were first found in Southern Africa where they are driving the current wave of infection. In this report, we perform an in-depth characterisation of the antigenicity of the BA.4/BA.5 Spike protein by comparing sera collected post-vaccination, post-BA.1 or BA.2 infection, or post breakthrough infection of vaccinated individuals with the Omicron variant. In addition, we assess sensitivity to neutralisation by commonly used therapeutic monoclonal antibodies. We find sera collected post-vaccination have a similar ability to neutralise BA.1, BA.2 and BA.4/BA.5. In contrast, in the absence of vaccination, prior infection with BA.2 or, in particular, BA.1 results in an antibody response that neutralises BA.4/BA.5 poorly. Breakthrough infection with Omicron in vaccinees leads to a broad neutralising response against the new variants. The sensitivity of BA.4/BA.5 to neutralisation by therapeutic monoclonal antibodies was similar to that of BA.2. These data suggest BA.4/BA.5 are antigenically distinct from BA.1 and, to a lesser extent, BA.2. The enhanced breadth of neutralisation observed following breakthrough infection with Omicron suggests that vaccination with heterologous or multivalent antigens may represent viable strategies for the development of cross-neutralising antibody responses.

5.
Elife ; 112022 05 19.
Article in English | MEDLINE | ID: covidwho-1856224

ABSTRACT

The outcome of infection is dependent on the ability of viruses to manipulate the infected cell to evade immunity, and the ability of the immune response to overcome this evasion. Understanding this process is key to understanding pathogenesis, genetic risk factors, and both natural and vaccine-induced immunity. SARS-CoV-2 antagonises the innate interferon response, but whether it manipulates innate cellular immunity is unclear. An unbiased proteomic analysis determined how cell surface protein expression is altered on SARS-CoV-2-infected lung epithelial cells, showing downregulation of activating NK ligands B7-H6, MICA, ULBP2, and Nectin1, with minimal effects on MHC-I. This occurred at the level of protein synthesis, could be mediated by Nsp1 and Nsp14, and correlated with a reduction in NK cell activation. This identifies a novel mechanism by which SARS-CoV-2 host-shutoff antagonises innate immunity. Later in the disease process, strong antibody-dependent NK cell activation (ADNKA) developed. These responses were sustained for at least 6 months in most patients, and led to high levels of pro-inflammatory cytokine production. Depletion of spike-specific antibodies confirmed their dominant role in neutralisation, but these antibodies played only a minor role in ADNKA compared to antibodies to other proteins, including ORF3a, Membrane, and Nucleocapsid. In contrast, ADNKA induced following vaccination was focussed solely on spike, was weaker than ADNKA following natural infection, and was not boosted by the second dose. These insights have important implications for understanding disease progression, vaccine efficacy, and vaccine design.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies , Antibodies, Viral , Humans , Killer Cells, Natural , Proteomics
6.
Int J Obes (Lond) ; 46(8): 1478-1486, 2022 Aug.
Article in English | MEDLINE | ID: covidwho-1852402

ABSTRACT

BACKGROUND: COVID-19 severity varies widely. Although some demographic and cardio-metabolic factors, including age and obesity, are associated with increasing risk of severe illness, the underlying mechanism(s) are uncertain. SUBJECTS/METHODS: In a meta-analysis of three independent studies of 1471 participants in total, we investigated phenotypic and genetic factors associated with subcutaneous adipose tissue expression of Angiotensin I Converting Enzyme 2 (ACE2), measured by RNA-Seq, which acts as a receptor for SARS-CoV-2 cellular entry. RESULTS: Lower adipose tissue ACE2 expression was associated with multiple adverse cardio-metabolic health indices, including type 2 diabetes (T2D) (P = 9.14 × 10-6), obesity status (P = 4.81 × 10-5), higher serum fasting insulin (P = 5.32 × 10-4), BMI (P = 3.94 × 10-4), and lower serum HDL levels (P = 1.92 × 10-7). ACE2 expression was also associated with estimated proportions of cell types in adipose tissue: lower expression was associated with a lower proportion of microvascular endothelial cells (P = 4.25 × 10-4) and higher proportion of macrophages (P = 2.74 × 10-5). Despite an estimated heritability of 32%, we did not identify any proximal or distal expression quantitative trait loci (eQTLs) associated with adipose tissue ACE2 expression. CONCLUSIONS: Our results demonstrate that individuals with cardio-metabolic features known to increase risk of severe COVID-19 have lower background ACE2 levels in this highly relevant tissue. Reduced adipose tissue ACE2 expression may contribute to the pathophysiology of cardio-metabolic diseases, as well as the associated increased risk of severe COVID-19.


Subject(s)
Adipose Tissue , Angiotensin-Converting Enzyme 2 , COVID-19 , Adipose Tissue/metabolism , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , COVID-19/complications , COVID-19/genetics , Cardiometabolic Risk Factors , Diabetes Mellitus, Type 2/genetics , Endothelial Cells/metabolism , Humans , Obesity , SARS-CoV-2
7.
Cell Rep ; 39(5): 110757, 2022 05 03.
Article in English | MEDLINE | ID: covidwho-1850799

ABSTRACT

Although the antibody response to COVID-19 vaccination has been studied extensively at the polyclonal level using immune sera, little has been reported on the antibody response at the monoclonal level. Here, we isolate a panel of 44 anti-SARS-CoV-2 monoclonal antibodies (mAbs) from an individual who received two doses of the ChAdOx1 nCoV-19 (AZD1222) vaccine at a 12-week interval. We show that, despite a relatively low serum neutralization titer, Spike-reactive IgG+ B cells are still detectable 9 months post-boost. Furthermore, mAbs with potent neutralizing activity against the current SARS-CoV-2 variants of concern (Alpha, Gamma, Beta, Delta, and Omicron) are present. The vaccine-elicited neutralizing mAbs form eight distinct competition groups and bind epitopes overlapping with neutralizing mAbs elicited following SARS-CoV-2 infection. AZD1222-elicited mAbs are more mutated than mAbs isolated from convalescent donors 1-2 months post-infection. These findings provide molecular insights into the AZD1222 vaccine-elicited antibody response.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Monoclonal , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Vaccination
8.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-337014

ABSTRACT

The second and third years of the SARS-CoV-2 pandemic have been marked by the repeated emergence and replacement of ‘variants’ with genetic and phenotypic distance from the ancestral strains, the most recent examples being Delta and Omicron. Here we describe a hamster contact exposure challenge model to assess protection conferred by vaccination or prior infection against re-infection. We found that 2-doses of self-amplifying RNA vaccine based on the ancestral spike ameliorated weight loss following Delta infection and decreased viral loads, but had minimal effect on Omicron/BA.1 infection. Prior infection with ancestral or Alpha variant was partially protective against Omicron/BA.1 infection, whereas all animals previously infected with Delta and exposed to Omicron became infected, although shed less virus. We further tested whether prior infection with Omicron/BA.1 protected from re-infection with Delta or Omicron/BA.2. Omicron/BA.1 was protective against Omicron/BA.2, but not Delta reinfection, again showing Delta and Omicron have a very large antigenic distance. Indeed, cross-neutralisation assays with human antisera from otherwise immunonaïve individuals (unvaccinated and no known prior infection), confirmed a large antigenic distance between Delta and Omicron. Prior vaccination followed by Omicron or Delta breakthrough infection led to a higher degree of cross-reactivity to all tested variants. To conclude, cohorts whose only immune experience of COVID is Omicron/BA.1 infection may be particularly vulnerable to future circulation of Delta or Delta-like derivatives. In contrast, repeated exposure to antigenically distinct spikes, via infection and or vaccination drives a more cross-reactive immune response, both in hamsters and people. One Sentence Summary Infection with the Delta and Omicron SARS-CoV-2 variants do not provide cross-protective immunity against reinfection with one another in hamsters.

9.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-337005

ABSTRACT

SARS-CoV-2 antibody levels can be used to assess humoral immune responses following SARS-CoV-2 infection or vaccination, and may predict risk of future infection. From cross-sectional antibody testing of 9,361 individuals from TwinsUK and ALSPAC UK population-based longitudinal studies (jointly in April-May 2021, and TwinsUK only in November 2021-January 2022), we tested associations between antibody levels following vaccination and: (1) SARS-CoV-2 infection following vaccination(s);(2) health, socio-demographic, SARS-CoV-2 infection and SARS-CoV-2 vaccination variables. Within TwinsUK, single-vaccinated individuals with the lowest 20% of anti-Spike antibody levels at initial testing had 3-fold greater odds of SARS-CoV-2 infection over the next six to nine months, compared to the top 20%. In TwinsUK and ALSPAC, individuals identified as at increased risk of COVID-19 complication through the UK “Shielded Patient List” had consistently greater odds (2 to 4-fold) of having antibody levels in the lowest 10%. Third vaccination increased absolute antibody levels for almost all individuals, and reduced relative disparities compared with earlier vaccinations. These findings quantify the association between antibody level and risk of subsequent infection, and support a policy of triple vaccination for the generation of protective antibodies. Lay summary In this study, we analysed blood samples from 9,361 participants from two studies in the UK: an adult twin registry, TwinsUK (4,739 individuals);and the Avon Longitudinal Study of Parents and Children, ALSPAC (4,622 individuals). We did this work as part of the UK Government National Core Studies initiative researching COVID-19. We measured blood antibodies which are specific to SARS-CoV-2 (which causes COVID-19). Having a third COVID-19 vaccination boosted antibody levels. More than 90% of people from TwinsUK had levels after third vaccination that were greater than the average level after second vaccination. Importantly, this was the case even in individuals on the UK “Shielded Patient List”. We found that people with lower antibody levels after first vaccination were more likely to report having COVID-19 later on, compared to people with higher antibody levels. People on the UK “Shielded Patient List”, and individuals who reported that they had poorer general health, were more likely to have lower antibody levels after vaccination. In contrast, people who had had a previous COVID-19 infection were more likely to have higher antibody levels following vaccination compared to people without infection. People receiving the Oxford/AstraZeneca rather than the Pfizer BioNTech vaccine had lower antibody levels after one or two vaccinations. However, after a third vaccination, there was no difference in antibody levels between those who had Oxford/AstraZeneca and Pfizer BioNTech vaccines for their first two doses. These findings support having a third COVID-19 vaccination to boost antibodies.

11.
Res Sq ; 2022 Mar 02.
Article in English | MEDLINE | ID: covidwho-1766251

ABSTRACT

This study tested if prior BCG revaccination can further boost immune responses subsequently induced by an otherwise efficacious Oxford/AstraZeneca ChAdOx1nCoV-19 vaccine, referred to as COVISHIELDTM in India. We compared COVISHIELDTM induced longitudinal immune responses in 21 BCG re-vaccinees (BCG-RV) and 13 BCG-non-revaccinees (BCG-NRV), all of whom were BCG vaccinated at birth and latent tuberculosis negative, after COVISHIELDTM prime and boost with baseline samples that were collected pre-pandemic and pre-BCG revaccination. Compared to BCG-NRV, BCG-RV displayed significantly higher magnitude of spike-specific Ab and T cell responses, including a greater proportion of high responders; better quality polyfunctional CD4 and CD8 T cells that persisted and a more robust Ab and T cell response to the Delta mutant of SARS-CoV-2 highlighting greater breadth. Mechanistically, BCG adjuvant effects on COVISHIELDTM induced adaptive responses was associated with more robust innate responses to pathogen-associated-molecular-patterns through TNF-α and IL-1ß secretion. This study highlights the potential of using a cheap and globally available vaccine as an adjuvant to enhance heterologous adaptive immune responses induced by COVIDSHIELDTM and other emerging vaccines.

12.
mBio ; 13(2): e0379821, 2022 04 26.
Article in English | MEDLINE | ID: covidwho-1745822

ABSTRACT

Numerous studies have shown that a prior SARS-CoV-2 infection can greatly enhance the antibody response to COVID-19 vaccination, with this so called "hybrid immunity" leading to greater neutralization breadth against SARS-CoV-2 variants of concern. However, little is known about how breakthrough infection (BTI) in COVID-19-vaccinated individuals will impact the magnitude and breadth of the neutralizing antibody response. Here, we compared neutralizing antibody responses between unvaccinated and COVID-19-double-vaccinated individuals (including both AZD1222 and BNT162b2 vaccinees) who have been infected with the Delta (B.1.617.2) variant. Rapid production of spike-reactive IgG was observed in the vaccinated group, providing evidence of effective vaccine priming. Overall, potent cross-neutralizing activity against current SARS-CoV-2 variants of concern was observed in the BTI group compared to the infection group, including neutralization of the Omicron (B.1.1.529) variant. This study provides important insights into population immunity where transmission levels remain high and in the context of new or emerging variants of concern. IMPORTANCE COVID-19 vaccines have been vital in controlling SARS-CoV-2 infections and reducing hospitalizations. However, breakthrough SARS-CoV-2 infections (BTI) occur in some vaccinated individuals. Here, we study how BTI impacts on the potency and the breadth of the neutralizing antibody response. We show that a Delta infection in COVID-19-vaccinated individuals provides potent neutralization against the current SARS-CoV-2 variants of concern, including the Omicron variant.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines , ChAdOx1 nCoV-19 , Humans , SARS-CoV-2/genetics
13.
EuropePMC;
Preprint in English | EuropePMC | ID: ppcovidwho-327777

ABSTRACT

Adenovirus vector vaccines have been widely and successfully deployed in response to COVID-19. However, despite inducing potent T cell immunity, improvement of vaccine-specific antibody responses upon homologous boosting is modest compared to other technologies. Here, we describe a system to enable modular decoration of adenovirus capsid surfaces with protein antigens and demonstrate induction of potent humoral immunity against these displayed antigens. Ligand attachment via a covalent isopeptide bond was achieved in a rapid and spontaneous reaction, requiring simple co-incubation of ligand and vector components. We used a recently described protein superglue, DogTag/DogCatcher, which is similar to the widely used SpyTag/SpyCatcher ligation system but performs better in loop structures. DogTag was inserted into surface-exposed loops in the adenovirus hexon protein to allow attachment of DogCatcher-fused ligands on virus particles. Efficient coverage of the capsid surface was achieved using a variety of ligands and vector infectivity was retained in each case. Capsid decoration shielded particles from anti-adenovirus neutralizing antibodies. In prime-boost regimens, proof-of-concept COVID-19 adenovirus vaccines decorated with the receptor-binding domain (RBD) of SARS-CoV-2 spike induced >10-fold higher SARS-CoV-2 neutralization titers compared to an undecorated adenovirus vector encoding spike. Importantly, decorated vectors retained robust T cell immunogenicity to encoded antigens, a key hallmark of adenovirus vector vaccines. We propose capsid decoration via protein superglue-mediated covalent ligation as a novel strategy to improve the efficacy and boostability of adenovirus-based vaccines and therapeutics.

14.
EuropePMC;
Preprint in English | EuropePMC | ID: ppcovidwho-327411

ABSTRACT

Objectives To assess T cell responses in individuals with and without a positive antibody response to SARS-CoV-2, in symptomatic and asymptomatic individuals during the COVID-19 pandemic. Methods Participants were drawn from the TwinsUK cohort, selected according to a) presence or absence of COVID-associated symptoms (S+, S-), logged prospectively through the COVID Symptom Study app, and b) Anti-IgG Spike and anti-IgG Nucleocapsid antibodies measured by ELISA (Ab+, Ab-), during the first wave of the UK pandemic. T cell helper and regulatory responses after stimulation with SARS-CoV-2 peptides were assessed. Results 32 participants were included in final analysis. 14 of 15 with IgG Spike antibodies had a T cell response to SARS-CoV-2-specific peptides;none of 17 participants without IgG Spike antibodies had a T cell response (Chi-squared 28.2, p<0.001). Quantitative T cell responses correlated strongly with fold-change in IgG Spike antibody titre (rho=0.79, p<0.0001) but not to symptom score (rho=0.17, p=0.35). Conclusions Humoral and cellular immune responses to SARS-CoV-2 are highly correlated, with no evidence that cellular immunity differs from antibody status four months after acute illness.

15.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-316788

ABSTRACT

Background: Cancer patients are vulnerable populations for COVID-19 complications and mortality. We previously reported on the poor single-dose immunogenicity of BNT162b2 mRNA vaccine in cancer patients, particularly those with haematological malignancies. Methods: In this prospective, observational study relating to the safety and immunogenicity of BNT162b2 mRNA vaccine, 201 vaccinated cancer patients (solid cancer n=125;haematological cancer n=76) and 54 healthy controls (mostly health-care workers “HCW”) were recruited between December 8th, 2020, and April 23rd, 2021. The previously reported interim results covered a period of 101 days since first patient recruitment, during which time 47 subjects received a second “boost” vaccination on day 21. Because of the change in UK Government policy, all others received a delayed vaccine boost at about 12 weeks after their first vaccination, and had their blood sampled 2 weeks’ later. Here, we describe immunogenicity data following the delayed boost in 31 HCWs, 72 solid cancer and 56 haematological cancer patients. Seroconversion, virus neutralisation, and T cell assays were as described previously, with an additional test for neutralisation of the B.1.617.2 (delta) variant-ofconcern (VOC). The primary endpoint of the study was the impact on seroconversion following delayed (>21days) vaccine boosting in solid and haematological cancer patients. The secondary endpoints were: safety following delayed vaccine boost;T cell responses;and neutralisation of SARS-CoV-2 Wuhan (“wild type” [WT]), B.1.1.7 (alpha), and B.1.617.2 (delta) variants.Findings: Delayed (>21days) boost vaccination of solid cancer patients and haematological cancer patients with the BNT162b2 vaccine was well tolerated, as the primary vaccination had been. There was no vaccine-associated death. Boosting significantly increased solid cancer patients’ seroconversion responses, that had been strikingly poor in response to a single dose: from 38% to 84%. Boosting also significantly improved vaccine immunogenicity for haematological cancer patients, but most (57%) still failed to seroconvert. Seroconversion correlated strongly with the capacity to neutralise SARSCoV- 2 cell entry, although neutralisation of the WT variant was typically greater than of the VOC. Neutralisation was significantly increased by boosting for HCWs but not for cancer patients. In comparison to seroconversion, boosting achieved higher rates of functional T cell responsiveness (de novo responses) but had little impact on the magnitude of T cell responses for those who had responded to first-dose vaccination. When patients were scored as showing both seroconversion and T cell responses, the unfavourable situation of haematological cancer patients was overt with only 36% (12/33) defined as being responders compared to 78% (25/32) of solid cancer patients and 88% (15/17) of HCWs. There was no significant difference in any aspect of immunogenicity for HCWs or solid cancer patients receiving the delayed boost versus the day 21 boost (this comparison could not be made for haematological cancer patients because too few received an early boost). Chemotherapy within 15 days either side of the boost exacerbated the likelihood of non-responsiveness to the vaccine.Interpretation: Boosting at either 3 weeks or longer (up to 12 weeks) post-primary vaccination shows high efficacy in terms of seroconversion of solid cancer patients and increases in their SARS-CoV-2 Spike-specific antibody titres. By contrast, delayed boosting left most haematological cancer patients without serological protection against SARS-CoV-2 infection. These data support the ongoing adjustment of health care measures to limit the evident vulnerability of such individuals to SARS-CoV- 2, and to limit their potential to transmit virus variants that might develop in the context of absent or partial immunoprotection. The absence of any clear improvements in immunogenicity of a delayed boost relative to boosting on day 21 emphasizes the importan e of early boosting for cancer patients, and potentially of doing so repeatedly, particularly given how well the vaccine was tolerated. Chemotherapy, if possible should be withheld 15 days before and 15 days after the vaccination date.Trial Registration: The trial is registered with the NHS Health Research Authority (HRA) and Health and Care Research Wales (HCRW) (REC ID: 20/HRA/2031).Funding: KCL, CRUK, Leukemia & Lymphoma Society, Wellcome Trust, Rosetrees Trust, Francis Crick Institute.Declaration of Interest: None to declare. Ethical Approval: The trial was approved by the institutional review boards of the participating institutions (IRAS ID: 282337 REC ID: 20/HRA/2031).

16.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-316696

ABSTRACT

Prognostic characteristics inform risk stratification in intensive care unit (ICU) patients with coronavirus disease 2019 (COVID-19). We obtained blood samples (n = 474) from hospitalized COVID-19 patients (n = 123), non-COVID-19 ICU sepsis patients (n = 25) and healthy controls (n = 30). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA was detected in plasma or serum (RNAemia) of COVID-19 ICU patients when neutralizing antibody response was low. RNAemia was associated with higher 28-day ICU mortality (hazard ratio [HR], 1.84 [95% CI, 1.22–2.77] adjusted for age and sex). In longitudinal comparisons, COVID-19 ICU patients had a distinct proteomic trajectory associated with RNAemia and mortality. Among COVID-19-enriched proteins, galectin-3 binding protein (LGALS3BP) and proteins of the complement system were identified as interaction partners of SARS-CoV-2 spike glycoprotein. Finally, machine learning identified ‘Age, RNAemia’ and ‘Age, pentraxin-3 (PTX3)’ as the best binary signatures associated with 28-day ICU mortality.

17.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-307811

ABSTRACT

We describe the innate and adaptive immune system trajectory in Multi-system inflammatory syndrome of childhood (MIS-C), at acute(within 72 hours of hospitalization), resolution (at clinical improvement) and convalescent phase. In our cohort, in the acute phase, 68% of the children were SARS-CoV-2 seropositive, with hypercytokinenemia (high interleukin(IL)-1beta,IL-6,IL-8,IL-10,IL-17, interferon gamma), procoagulant state, myocardial dysfunction, activated neutrophils and monocytes;differential T and B cell subset lymphopenia;activated chemokine receptor type-7 positive and gamma-delta T cell subsets;antigen presenting cells had reduced HLA-DR expression;and B-cell class-switch responses occurred with illness resolution. MIS-C is an immunopathogenic illness associated with SARS-CoV-2 infections in children.

18.
J Clin Invest ; 132(2)2022 01 18.
Article in English | MEDLINE | ID: covidwho-1633624

ABSTRACT

Memory B cells (MBCs) can provide a recall response able to supplement waning antibodies (Abs) with an affinity-matured response better able to neutralize variant viruses. We studied a cohort of elderly care home residents and younger staff (median age of 87 years and 56 years, respectively), who had survived COVID-19 outbreaks with only mild or asymptomatic infection. The cohort was selected because of its high proportion of individuals who had lost neutralizing antibodies (nAbs), thus allowing us to specifically investigate the reserve immunity from SARS-CoV-2-specific MBCs in this setting. Class-switched spike and receptor-binding domain (RBD) tetramer-binding MBCs persisted 5 months after mild or asymptomatic SARS-CoV-2 infection, irrespective of age. The majority of spike- and RBD-specific MBCs had a classical phenotype, but we found that activated MBCs, indicating possible ongoing antigenic stimulation or inflammation, were expanded in the elderly group. Spike- and RBD-specific MBCs remained detectable in the majority of individuals who had lost nAbs, although at lower frequencies and with a reduced IgG/IgA isotype ratio. Functional spike-, S1 subunit of the spike protein- (S1-), and RBD-specific recall was also detectable by enzyme-linked immune absorbent spot (ELISPOT) assay in some individuals who had lost nAbs, but was significantly impaired in the elderly. Our findings demonstrate that a reserve of SARS-CoV-2-specific MBCs persists beyond the loss of nAbs but highlight the need for careful monitoring of functional defects in spike- and RBD-specific B cell immunity in the elderly.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , Immunologic Memory , SARS-CoV-2/immunology , COVID-19/epidemiology , Female , Humans , Immunoglobulin Class Switching , Male , Spike Glycoprotein, Coronavirus/immunology
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