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1.
Eur J Neurol ; 2023 Jun 13.
Article in English | MEDLINE | ID: covidwho-20238912

ABSTRACT

BACKGROUND AND PURPOSE: An enhanced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine regimen could improve humoral vaccine response in patients with multiple sclerosis (MS) treated by anti-CD20. The aim was to evaluate the serological response and the neutralizing activity after BNT162b2 primary and booster vaccination in MS patients, including patients on anti-CD20 receiving a primary vaccine regimen enhanced with three injections. METHODS: In this prospective longitudinal cohort study of 90 patients (47 on anti-CD20, 10 on fingolimod, 33 on natalizumab, dimethylfumarate or teriflunomide), anti-SARS-CoV-2 receptor binding domain (RBD) immunoglobulin G antibodies were quantified and their neutralization capacity was evaluated by enzyme-linked immunosorbent assay (GenScript) and a virus neutralization test against B.1 historical strain, Delta and Omicron variants, before and after three to four BNT162b2 injections. RESULTS: After the primary vaccination scheme, the anti-RBD positivity rate was strongly decreased in patients on anti-CD20 (28% [15%; 44%] after two shots, 45% [29%; 62%] after three shots) and fingolimod (50% [16%; 84%]) compared to other treatments (100% [90%; 100%]). Neutralization activity was also decreased in patients on anti-CD20 and fingolimod, and notably low for the Omicron variant in all patients (0%-22%). Delayed booster vaccination was performed in 54 patients, leading to a mild increase of anti-RBD seropositivity in patients on anti-CD20 although it was still lower compared to other treatments (65% [43%; 84%] vs. 100% [87%; 100%] respectively). After a booster, Omicron neutralization activity remained low on anti-CD20 and fingolimod treated patients but was strongly increased in patients on other treatments (91% [72%; 99%]). DISCUSSION: In MS patients on anti-CD20, an enhanced primary vaccination scheme moderately increased anti-RBD seropositivity and anti-RBD antibody titre, but neutralization activity remained modest even after a fourth booster injection. TRIAL REGISTRATION INFORMATION: COVIVAC-ID, NCT04844489, first patient included on 20 April 2021.

4.
Free Neuropathol ; 42023 Jan.
Article in English | MEDLINE | ID: covidwho-2252547

ABSTRACT

In a neuropathological series of 20 COVID-19 cases, we analyzed six cases (three biopsies and three autopsies) with multiple foci predominantly affecting the white matter as shown by MRI. The cases presented with microhemorrhages evocative of small artery diseases. This COVID-19 associated cerebral microangiopathy (CCM) was characterized by perivascular changes: arterioles were surrounded by vacuolized tissue, clustered macrophages, large axonal swellings and a crown arrangement of aquaporin-4 immunoreactivity. There was evidence of blood-brain-barrier leakage. Fibrinoid necrosis, vascular occlusion, perivascular cuffing and demyelination were absent. While no viral particle or viral RNA was found in the brain, the SARS-CoV-2 spike protein was detected in the Golgi apparatus of brain endothelial cells where it closely associated with furin, a host protease known to play a key role in virus replication. Endothelial cells in culture were not permissive to SARS-CoV-2 replication. The distribution of the spike protein in brain endothelial cells differed from that observed in pneumocytes. In the latter, the diffuse cytoplasmic labeling suggested a complete replication cycle with viral release, notably through the lysosomal pathway. In contrast, in cerebral endothelial cells the excretion cycle was blocked in the Golgi apparatus. Interruption of the excretion cycle could explain the difficulty of SARS-CoV-2 to infect endothelial cells in vitro and to produce viral RNA in the brain. Specific metabolism of the virus in brain endothelial cells could weaken the cell walls and eventually lead to the characteristic lesions of COVID-19 associated cerebral microangiopathy. Furin as a modulator of vascular permeability could provide some clues for the control of late effects of microangiopathy.

5.
Life (Basel) ; 12(12)2022 Dec 09.
Article in English | MEDLINE | ID: covidwho-2155189

ABSTRACT

The SARS-CoV-2 neutralizing antibodies response is the best indicator of effective protection after infection and/or vaccination, but its evaluation requires tedious cell-based experiments using an infectious virus. We analyzed, in 105 patients with various histories of SARS-CoV-2 infection and/or vaccination, the neutralizing response using a virus neutralization test (VNT) against B.1, Alpha, Beta and Omicron variants, and compared the results with two surrogate assays based on antibody-mediated blockage of the ACE2-RBD interaction (Lateral Flow Boditech and ELISA Genscript). The strongest response was observed for recovered COVID-19 patients receiving one vaccine dose. Naïve patients receiving 2 doses of mRNA vaccine also demonstrate high neutralization titers against B.1, Alpha and Beta variants, but only 34.3% displayed a neutralization activity against the Omicron variant. On the other hand, non-infected patients with half vaccination schedules displayed a weak and inconstant activity against all isolates. Non-vaccinated COVID-19 patients kept a neutralizing activity against B.1 and Alpha up to 12 months after recovery but a decreased activity against Beta and Omicron. Both surrogate assays displayed a good correlation with the VNT. However, an adaptation of the cut-off positivity was necessary, especially for the most resistant Beta and Omicron variants. We validated two simple and reliable surrogate neutralization assays, which may favorably replace cell-based methods, allowing functional analysis on a larger scale.

6.
AIDS ; 36(11): 1545-1552, 2022 Sep 01.
Article in English | MEDLINE | ID: covidwho-1992434

ABSTRACT

OBJECTIVES: To assess humoral responses to SARS-CoV-2 Delta-variant in people with HIV (PWH) after BNT162b2-vaccination. DESIGN: Multicenter cohort study of PWH with CD4 + cell count less than 500 cells/µl and viral load less than 50 copies/ml on stable antiretroviral therapy for at least 3 months. METHODS: Anti-SARS-CoV-2 receptor-binding-domain IgG antibodies (anti-RBD IgG) were quantified and neutralization capacity was evaluated by ELISA/GenScript and virus-neutralization-test against the D614G-strain, beta and delta variants before vaccination (day 0) and 1 month after complete schedule (M1). RESULTS: We enrolled 97 PWH, 85 received two vaccine shots. The seroconversion rate for anti-RBD IgG was 97% [95% confidence interval (CI) 90-100%] at M1. Median (IQR) anti-RBD IgG titer was 0.97 (0.97-5.3) BAU/ml at D0 and 1219 (602-1929) at M1. Neutralization capacity improved between D0 (15%; 50% CI 8-23%) and M1 (94%; 95% CI 87-98%) ( P  < 0.0001). At M1, NAbs against the D614G strain, beta and delta variants were present in 82, 77, and 84% PWH, respectively. The seroconversion rate and median anti-RBD-IgG level were 91% and 852 BAU/ml, respectively, in PWH with CD4 + cell count less than 250 ( n  = 13) and 98% and 1270 BAU/ml for CD4 + greater than 250 ( n  = 64) ( P  = 0.3994). NAbs were present in 73% of PWH with CD4 + less than 250 and 97% of those with CD4 + cell count greater than 250 ( P  = 0.0130). NAbs against beta variant were elicited in 50% in PWH with CD4 + cell count less than 250 and in 81% of those with CD4 + cell count greater than 250 ( P  = 0.0292). CD4 + and CD8 + T-cell counts were unchanged, whereas CD19 + B-cell counts decreased after vaccination(208 ±â€Š124 at D0 vs. 188 ±â€Š112 at M1, P  < 0.01). No notable adverse effects or COVID-19 cases were reported. CONCLUSION: Seroconversion rates were high, with delta-neutralization rates similar to those for the D61G strain, after a two-dose BNT162b2 vaccination in PWH.


Subject(s)
COVID-19 , HIV Infections , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , Cohort Studies , Humans , Immunoglobulin G , SARS-CoV-2 , Seroconversion , Vaccination
7.
Front Immunol ; 13: 844727, 2022.
Article in English | MEDLINE | ID: covidwho-1834403

ABSTRACT

The immunopathological pulmonary mechanisms leading to Coronavirus Disease (COVID-19)-related death in adults remain poorly understood. Bronchoalveolar lavage (BAL) and peripheral blood sampling were performed in 74 steroid and non-steroid-treated intensive care unit (ICU) patients (23-75 years; 44 survivors). Peripheral effector SARS-CoV-2-specific T cells were detected in 34/58 cases, mainly directed against the S1 portion of the spike protein. The BAL lymphocytosis consisted of T cells, while the mean CD4/CD8 ratio was 1.80 in non-steroid- treated patients and 1.14 in steroid-treated patients. Moreover, strong BAL SARS-CoV-2 specific T-cell responses were detected in 4/4 surviving and 3/3 non-surviving patients. Serum IFN-γ and IL-6 levels were decreased in steroid-treated patients when compared to non-steroid treated patients. In the lung samples from 3 (1 non-ICU and 2 ICU) additional deceased cases, a lymphocytic memory CD4 T-cell angiopathy colocalizing with SARS-CoV-2 was also observed. Taken together, these data show that disease severity occurs despite strong antiviral CD4 T cell-specific responses migrating to the lung, which could suggest a pathogenic role for perivascular memory CD4 T cells upon fatal COVID-19 pneumonia.


Subject(s)
COVID-19 , Pneumonia , Adult , CD4-Positive T-Lymphocytes , CD8-Positive T-Lymphocytes , Humans , Lung , SARS-CoV-2
8.
Clin Infect Dis ; 74(4): 707-710, 2022 03 01.
Article in English | MEDLINE | ID: covidwho-1703814

ABSTRACT

There are concerns about neutralizing antibodies' (NAbs') potency against severe acute respiratory syndrome coronavirus 2 variants. Despite decreased NAb titers elicited by BNT162b2 vaccine against VOC202012/01 and 501Y.V2 strains, 28/29 healthcare workers (HCWs) had an NAb titer ≥1:10. In contrast, 6 months after coronavirus disease 2019 mild forms, only 9/15 (60%) of HCWs displayed detectable NAbs against 501Y.V2 strain.


Subject(s)
COVID-19 , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , Health Personnel , Humans , SARS-CoV-2/genetics , United Kingdom/epidemiology
9.
Front Immunol ; 12: 761250, 2021.
Article in English | MEDLINE | ID: covidwho-1556220

ABSTRACT

Amino acid substitutions and deletions in the Spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants can reduce the effectiveness of monoclonal antibodies (mAbs). In contrast, heterologous polyclonal antibodies raised against S protein, through the recognition of multiple target epitopes, have the potential to maintain neutralization capacities. XAV-19 is a swine glyco-humanized polyclonal neutralizing antibody raised against the receptor binding domain (RBD) of the Wuhan-Hu-1 Spike protein of SARS-CoV-2. XAV-19 target epitopes were found distributed all over the RBD and particularly cover the receptor binding motives (RBMs), in direct contact sites with the angiotensin converting enzyme-2 (ACE-2). Therefore, in Spike/ACE-2 interaction assays, XAV-19 showed potent neutralization capacities of the original Wuhan Spike and of the United Kingdom (Alpha/B.1.1.7) and South African (Beta/B.1.351) variants. These results were confirmed by cytopathogenic assays using Vero E6 and live virus variants including the Brazil (Gamma/P.1) and the Indian (Delta/B.1.617.2) variants. In a selective pressure study on Vero E6 cells conducted over 1 month, no mutation was associated with the addition of increasing doses of XAV-19. The potential to reduce viral load in lungs was confirmed in a human ACE-2 transduced mouse model. XAV-19 is currently evaluated in patients hospitalized for COVID-19-induced moderate pneumonia in phase 2a-2b (NCT04453384) where safety was already demonstrated and in an ongoing 2/3 trial (NCT04928430) to evaluate the efficacy and safety of XAV-19 in patients with moderate-to-severe COVID-19. Owing to its polyclonal nature and its glyco-humanization, XAV-19 may provide a novel safe and effective therapeutic tool to mitigate the severity of coronavirus disease 2019 (COVID-19) including the different variants of concern identified so far.


Subject(s)
Antibodies, Heterophile/immunology , Antibodies, Viral/immunology , Broadly Neutralizing Antibodies/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Animals , Antibodies, Heterophile/therapeutic use , Antibodies, Viral/therapeutic use , Antigenic Variation , Broadly Neutralizing Antibodies/therapeutic use , COVID-19/therapy , COVID-19/virology , Disease Models, Animal , Epitopes , Humans , Immunization, Passive , Lung/drug effects , Lung/virology , Mice , Protein Interaction Domains and Motifs , Spike Glycoprotein, Coronavirus/genetics , Swine , Viral Load/drug effects , COVID-19 Serotherapy
11.
Nat Commun ; 12(1): 844, 2021 02 08.
Article in English | MEDLINE | ID: covidwho-1069105

ABSTRACT

There are only few data concerning persistence of neutralizing antibodies (NAbs) among SARS-CoV-2-infected healthcare workers (HCW). These individuals are particularly exposed to SARS-CoV-2 infection and at potential risk of reinfection. We followed 26 HCW with mild COVID-19 three weeks (D21), two months (M2) and three months (M3) after the onset of symptoms. All the HCW had anti-receptor binding domain (RBD) IgA at D21, decreasing to 38.5% at M3 (p < 0.0001). Concomitantly a significant decrease in NAb titers was observed between D21 and M2 (p = 0.03) and between D21 and M3 (p < 0.0001). Here, we report that SARS-CoV-2 can elicit a NAb response correlated with anti-RBD antibody levels. However, this neutralizing activity declines, and may even be lost, in association with a decrease in systemic IgA antibody levels, from two months after disease onset. This short-lasting humoral protection supports strong recommendations to maintain infection prevention and control measures in HCW, and suggests that periodic boosts of SARS-CoV-2 vaccination may be required.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , Health Personnel/statistics & numerical data , SARS-CoV-2/immunology , Adult , Binding Sites/immunology , COVID-19/virology , Cell Line, Tumor , Female , Humans , Immunoglobulin A/immunology , Male , Middle Aged , Protein Binding , Receptors, Virus/metabolism , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Time Factors
12.
Clin Microbiol Infect ; 26(11): 1560.e1-1560.e4, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-670663

ABSTRACT

OBJECTIVES: Studies are needed to better understand the genomic evolution of the recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This study aimed to describe genomic diversity of SARS-CoV-2 by next-generation sequencing (NGS) in a patient with longitudinal follow-up for SARS-CoV-2 infection. METHODS: Sequential samples collected between January 29th and February 4th, 2020, from a patient infected by SARS-CoV-2 were used to perform amplification of two genome fragments-including genes encoding spike, envelope, membrane and nucleocapsid proteins-and NGS was carried out with Illumina® technology. Phylogenetic analysis was performed with PhyML and viral variant identification with VarScan. RESULTS: Majority consensus sequences were identical in most of the samples (5/7) and differed in one synonymous mutation from the Wuhan reference sequence. We identified 233 variants; each sample harboured in median 38 different minority variants, and only four were shared by different samples. The frequency of mutation was similar between genes and correlated with the length of the gene (r = 0.93, p = 0.0002). Most of mutations were substitution variations (n = 217, 93.1%) and about 50% had moderate or high impact on gene expression. Viral variants also differed between lower and upper respiratory tract samples collected on the same day, suggesting independent sites of replication of SARS-CoV-2. CONCLUSIONS: We report for the first time minority viral populations representing up to 1% during the course of SARS-CoV-2 infection. Quasispecies were different from one day to the next, as well as between anatomical sites, suggesting that in vivo this new coronavirus appears as a complex and dynamic distributions of variants.


Subject(s)
Betacoronavirus/genetics , Betacoronavirus/isolation & purification , Coronavirus Infections/virology , Pneumonia, Viral/virology , Quasispecies/genetics , Betacoronavirus/classification , COVID-19 , Follow-Up Studies , Genome, Viral/genetics , Humans , Mutation , Pandemics , Phylogeny , SARS-CoV-2 , Viral Proteins/genetics
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