Autoantibodies against type I IFNs in patients with life-threatening COVID-19

Interindividual clinical variability in the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is vast. We report that at least 101 of 987 patients with life-threatening coronavirus disease 2019 (COVID-19) pneumonia had neutralizing immunoglobulin G (IgG) autoantibodies (auto-Abs) against interferon-w (IFN-w) (13 patients), against the 13 types of IFN-a (36), or against both (52) at the onset of critical disease; a few also had auto-Abs against the other three type I IFNs. The auto-Abs neutralize the ability of the corresponding type I IFNs to block SARS-CoV-2 infection in vitro. These auto-Abs were not found in 663 individuals with asymptomatic or mild SARS-CoV-2 infection and were present in only 4 of 1227 healthy individuals. Patients with auto-Abs were aged 25 to 87 years and 95 of the 101 were men. A B cell autoimmune phenocopy of inborn errors of type I IFN immunity accounts for life-threatening COVID-19 pneumonia in at least 2.6% of women and 12.5% of men

Rare predicted loss-of-function variants of type I IFN immunity genes are associated with life-threatening COVID-19

Background: We previously reported that impaired type I IFN activity, due to inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity or to autoantibodies against type I IFN, account for 15–20% of cases of life-threatening COVID-19 in unvaccinated patients. Therefore, the determinants of life-threatening COVID-19 remain to be identified in ~ 80% of cases. Methods: We report here a genome-wide rare variant burden association analysis in 3269 unvaccinated patients with life-threatening COVID-19, and 1373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. Among the 928 patients tested for autoantibodies against type I IFN, a quarter (234) were positive and were excluded. Results: No gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI 1.5–528.7, P = 1.1 × 10−4) for biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR = 3.70[95%CI 1.3–8.2], P = 2.1 × 10−4). This enrichment was further strengthened by (1) adding the recently reported TYK2 and TLR7 COVID-19 loci, particularly under a recessive model (OR = 19.65[95%CI 2.1–2635.4], P = 3.4 × 10−3), and (2) considering as pLOF branchpoint variants with potentially strong impacts on splicing among the 15 loci (OR = 4.40[9%CI 2.3–8.4], P = 7.7 × 10−8). Finally, the patients with pLOF/bLOF variants at these 15 loci were significantly younger (mean age [SD] = 43.3 [20.3] years) than the other patients (56.0 [17.3] years; P = 1.68 × 10−5). Conclusions: Rare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old

Unusual bleeding

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Longitudinal Cytokine Profiling in Severe COVID-19 Patients on ECMO and Haemoadsorption

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Ocular tolerance in rabbits after intracameral administration of a fixed combination of tropicamide, phenylephrine, and lidocaine with and without rinsing

Purpose: To evaluate the safety and tolerability of a single intracameral administration of a combined mydriatic (tropicamide and phenylephrine) and anesthetic (lidocaine) formulation (Mydrane) with or without rinsing.Setting: Iris Pharma, La Gaude, France.Design: Experimental study.Methods: Sixty pigmented rabbits received 100 mu L or 200 mu L of the combination product or a placebo (sodium chloride 0.9%) by intracameral injection. For the combination product, separate groups were included with and without rinsing after administration. From day 1 day to day 7, assessments included general clinical and ocular observations, pupil diameter measurements, corneal assessments, confocal microscopy, and electroretinography (ERG). Necropsy examinations were performed at study completion at day 8.Results: Rapid mydriasis, stable 24 minutes after injection and returning to baseline levels by day 1, was induced in all groups that received the combination mydriatic and anesthetic drug. Rinsing had no effect. The combination product induced no adverse effects on the anterior or posterior segment of the eye (ie, no increased corneal thickness and endothelial cell loss, no abnormalities in ERG). Slitlamp examination showed slightly increased anterior chamber inflammation with rinsing in both the study group and placebo group. This observation was not confirmed by aqueous flare examination. No toxic effects of the products were found on histological evaluation.Conclusion: The combination mydriatic and anesthetic drug administered to pigmented rabbits as a single intracameral injection at volumes of 100 mu L and 200 mu L was well tolerated with no ocular adverse effects and no effect on the corneal endothelium.</p

Nucleocapsid-specific and PD-L1+CXCR3+ CD8 polyfunctional T-cell abundances are associated with survival of critical SARS-CoV2-infected patients

International audienceRationale. The importance of the adaptative T cell response in the control and resolution of viral infection has been well-established. However, the nature of T cell-mediated viral control mechanisms in life-threatening stages of COVID-19 has yet to be determined.Objective. The aim of the present study was to determine the function and phenotype of T cell populations associated with survival or death of COVID-19 patients under intensive care as a result of phenotypic and functional profiling by mass cytometry.Findings. Increased frequencies of circulating, polyfunctional, CD4+CXCR5+HLA-DR+ stem cell memory T cells (TSCM) and decreased proportions of Granzyme-B and Perforin-expressing effector memory T cells (TEM) were detected in recovered and deceased patients, respectively. The higher abundance of polyfunctional CD8+PD-L1+CXCR3+ T effector cells, CXCR5+HLA-DR+ TSCM, as well as anti-nucleocapsid (NC) cytokine-producing T cells permitted to differentiate between recovered and deceased patients. The results from a principal component analysis showed an imbalance in the T cell compartment allowed for the separation of recovered and deceased patients. The paucity of circulating CD8+PD-L1+CXCR3+ Teff-cells and NC-specific CD8+ T-cells accurately forecasts fatal disease outcome.Conclusion. This study provides insight into the nature of the T cell populations involved in the control of COVID-19 and therefor might impact T cell-based vaccine designs for this infectious disease

LOX-1-Expressing Immature Neutrophils Identify Critically-Ill COVID-19 Patients at Risk of Thrombotic Complications

International audienceBackground: Lymphopenia and the neutrophil/lymphocyte ratio may have prognostic value in COVID-19 severity.Objective: We investigated neutrophil subsets and functions in blood and bronchoalveolar lavage (BAL) of COVID-19 patients on the basis of patients’ clinical characteristics.Methods: We used a multiparametric cytometry profiling based to mature and immature neutrophil markers in 146 critical or severe COVID-19 patients.Results: The Discovery study (38 patients, first pandemic wave) showed that 80% of Intensive Care Unit (ICU) patients develop strong myelemia with CD10−CD64+ immature neutrophils (ImNs). Cellular profiling revealed three distinct neutrophil subsets expressing either the lectin‐like oxidized low‐density lipoprotein receptor‐1 (LOX‐1), the interleukin-3 receptor alpha (CD123), or programmed death-ligand 1 (PD-L1) overrepresented in ICU patients compared to non-ICU patients. The proportion of LOX-1- or CD123-expressing ImNs is positively correlated with clinical severity, cytokine storm (IL-1β, IL-6, IL-8, TNFα), acute respiratory distress syndrome (ARDS), and thrombosis. BALs of patients with ARDS were highly enriched in LOX-1-expressing ImN subsets and in antimicrobial neutrophil factors. A validation study (118 patients, second pandemic wave) confirmed and strengthened the association of the proportion of ImN subsets with disease severity, invasive ventilation, and death. Only high proportions of LOX-1-expressing ImNs remained strongly associated with a high risk of severe thrombosis independently of the plasma antimicrobial neutrophil factors, suggesting an independent association of ImN markers with their functions.Conclusion: LOX-1-expressing ImNs may help identifying COVID-19 patients at high risk of severity and thrombosis complications

Elevated Neopterin Levels Predict Fatal Outcome in SARS-CoV-2-Infected Patients

International audienceHighlights: Innate immune activation during Covid-19 infection is associated with pernicious clinical outcome.Background: Coronavirus disease 2019 (Covid-19) is a worldwide threat that has already caused more than 3 000 000 deaths. It is characterized by different patterns of disease evolution depending on host factors among which old-age and pre-existing comorbidities play a detrimental role. Previous coronavirus epidemics, notably SARS-CoV, were associated with increased serum neopterin levels, which can be interpreted as a sign of acute innate immunity in response to viral infection. Here we hypothesize that neopterin may serve as a biomarker of SARS-CoV-2 viral infection and Covid-19 disease severity.Methods: We measured neopterin blood levels by ELISA. Seric concentration was quantified from 256 healthy donors and 374 Covid-19 patients at hospital admission. Enrolled Covid-19 patients were all symptomatic and displayed a large spectrum of comorbidities. Patients were followed until disease resolution or death.Results: Severe and critically ill SARS-CoV-2 infected patients were characterized by a profound exacerbation of immune activation characterized by elevated neopterin blood levels. Systemic neopterin levels above 19nM stratified healthy individuals from Covid-19 patients with 87% specificity and 100% sensitivity. Moreover, systemic neopterin levels above 53nM differentiated non-survivors from survivors with 64% specificity and 100% sensitivity.Conclusion: We propose that neopterin concentration measured at arrival to hospital is a hallmark of severe Covid-19 and identifies a high-risk population of pernicious clinical outcome with a need for special medical care

Lower disease activity but higher risk of severe COVID-19 and herpes zoster in systemiclupus erythematosus patients with pre-existing autoantibodies neutralising IFN-

International audienceObjectives: Type-I interferons (IFNs-I) have potent antiviral effects. IFNs-I are alsooverproduced in patients with systemic lupus erythematosus (SLE). Auto-antibodies (AAbs)neutralising IFN-, - and/or - subtypes are strong determinants of hypoxemic COVID-19pneumonia, but their impact on inflammation remains unknown.Methods: We retrospectively analysed a monocentric longitudinal cohort of 609 patients withSLE. Serum AAbs against IFN-α were quantified by ELISA and functionally assessed byabolishment of Madin-Darby bovine kidney cells protection by IFN-α2 against vesicularstomatitis virus challenge. Serum neutralising activity against IFN-, - and - was alsodetermined with a reporter luciferase activity. SARS-CoV-2 antibody responses were measuredagainst wild-type spike antigen, while serum-neutralising activity was assessed against theSARS-CoV-2 historical strain and variants of concerns.Results: Neutralising and non-neutralising anti-IFN- antibodies are present at a frequency of3.3% and 8.4%, respectively, in individuals with SLE. AAbs neutralising IFN-, unlike nonneutralisingAAbs, are associated with reduced IFN- serum levels and a reduced likelihood todevelop active disease. However, they predispose patients to an increased risk of herpes zosterand severe COVID-19 pneumonia. Severe COVID-19 pneumonia in patients with SLE ismostly associated with combined neutralisation of different IFNs-I. Finally, anti-IFN-AAbsdo not interfere with COVID-19 vaccine humoral immunogenicity.Conclusion: The production of non-neutralising and neutralising anti-IFN-I antibodies in SLEis likely to be a consequence of SLE-associated high IFN-I serum levels, with a beneficialeffect on disease activity, yet a greater viral risk. This finding reinforces the recommendationsfor vaccination against SARS-CoV-2 in SLE