The emergence of SARS-CoV-2 variants with mutations in the spike protein is raising concerns about the efficacy of infection- or vaccine-induced antibodies. We compared antibody binding and live ...virus neutralization of sera from naturally infected and Moderna-vaccinated individuals against two SARS-CoV-2 variants: B.1 containing the spike mutation D614G and the emerging B.1.351 variant containing additional spike mutations and deletions. Sera from acutely infected and convalescent COVID-19 patients exhibited a 3-fold reduction in binding antibody titers to the B.1.351 variant receptor-binding domain of the spike protein and a 3.5-fold reduction in neutralizing antibody titers against SARS-CoV-2 B.1.351 variant compared to the B.1 variant. Similar results were seen with sera from Moderna-vaccinated individuals. Despite reduced antibody titers against the B.1.351 variant, sera from infected and vaccinated individuals containing polyclonal antibodies to the spike protein could still neutralize SARS-CoV-2 B.1.351, suggesting that protective humoral immunity may be retained against this variant.
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•Antibodies from infected and vaccinated individuals bind to the B.1.351 RBD•Convalescent sera through eight months can neutralize the B.1.351 variant•Serum from vaccinated individuals retains neutralization against the B.1.351 variant
In this study, Edara et al. (2021) report that, despite reduced antibody binding to the B.1.351 RBD, sera from infected (acute and convalescent) and Moderna (mRNA-1273)-vaccinated individuals were still able to neutralize the SARS-CoV-2 B.1.351 variant, suggesting that protective humoral immunity may be retained against this variant.
Abstract
Severe COVID-19 and multisystem inflammatory syndrome in children (MIS-C) are characterized by hyperinflammation. Severe COVID in adults is associated with development of afucosylated ...SARS-CoV-2 IgG that induce monocytes to secrete inflammatory cytokines. This study aimed to analyze the relationship between spike IgG Fc glycosylation and inflammatory markers during acute pediatric COVID or MIS-C or following COVID vaccination in adults.
We assessed cross-sectional and longitudinal samples from 195 participants: Adult vaccinees, acute COVID patients, and healthy controls, as well as pediatric acute COVID patients, MIS-C patients, and healthy controls. We developed capillary electrophoresis (CE) methods to analyze bulk and spike IgG Fc glycans and measured ten relevant cytokines/chemokines by multiplexed assay.
Analysis of healthy control bulk IgG by CE found 95.3–99.6% fucosylated, 2.7–6.9% bisected, 55.8–66.8% galactosylated, and 4.6–15.6% sialylated Fc glycans, compared to 99.8%, 6.7%, 45.4%, and 8.2% by mass spectrometry, respectively. IFN-γ, IL-10, CXCL10, and CCL3 were significantly increased in MIS-C compared to pediatric healthy controls; IL-10, CCL2, and TNF were only increased in severe adult COVID compared to healthy controls or less severe COVID. Initial results confirmed significantly more afucosylated spike IgG in adult severe COVID than afucosylated bulk IgG in controls.
Our high-throughput methods for IgG Fc glycan profiling generated comparable results to mass spectrometry. Continued assessment will determine if COVID- or vaccine-induced spike IgG glycoforms correlate with inflammatory markers. Future mechanistic work will examine how modified glycosylation induces inflammatory cytokines.
Supported by an IDCRC New Investigator Pilot Award to E.M.S. (NIH UM1AI148684), by the Centers for Disease Control and Prevention through a cooperative agreement with the Georgia Emerging Infection Program (grant no. U50CK000485), and by grant from NIH to P.A. (R24GM137782).
The clinical trajectory of COVID-19 may be influenced by previous responses to heterologous viruses. We examined the relationship of Abs against different viruses to clinical trajectory groups from ...the National Institutes of Health IMPACC (Immunophenotyping Assessment in a COVID-19 Cohort) study of hospitalized COVID-19 patients. Whereas initial Ab titers to SARS-CoV-2 tended to be higher with increasing severity (excluding fatal disease), those to seasonal coronaviruses trended in the opposite direction. Initial Ab titers to influenza and parainfluenza viruses also tended to be lower with increasing severity. However, no significant relationship was observed for Abs to other viruses, including measles, CMV, EBV, and respiratory syncytial virus. We hypothesize that some individuals may produce lower or less durable Ab responses to respiratory viruses generally (reflected in lower baseline titers in our study), and that this may carry over into poorer outcomes for COVID-19 (despite high initial SARS-CoV-2 titers). We further looked at longitudinal changes in Ab responses to heterologous viruses, but found little change during the course of acute COVID-19 infection. We saw significant trends with age for Ab levels to many of these viruses, but no difference in longitudinal SARS-CoV-2 titers for those with high versus low seasonal coronavirus titers. We detected no difference in longitudinal SARS-CoV-2 titers for CMV seropositive versus seronegative patients, although there was an overrepresentation of CMV seropositives among the IMPACC cohort, compared with expected frequencies in the United States population. Our results both reinforce findings from other studies and suggest (to our knowledge) new relationships between the response to SARS-CoV-2 and Abs to heterologous viruses.
Age is a major risk factor for severe coronavirus disease 2019 (COVID-19), yet the mechanisms behind this relationship have remained incompletely understood. To address this, we evaluated the impact ...of aging on host immune response in the blood and the upper airway, as well as the nasal microbiome in a prospective, multicenter cohort of 1031 vaccine-naïve patients hospitalized for COVID-19 between 18 and 96 years old. We performed mass cytometry, serum protein profiling, anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody assays, and blood and nasal transcriptomics. We found that older age correlated with increased SARS-CoV-2 viral abundance upon hospital admission, delayed viral clearance, and increased type I interferon gene expression in both the blood and upper airway. We also observed age-dependent up-regulation of innate immune signaling pathways and down-regulation of adaptive immune signaling pathways. Older adults had lower naïve T and B cell populations and higher monocyte populations. Over time, older adults demonstrated a sustained induction of pro-inflammatory genes and serum chemokines compared with younger individuals, suggesting an age-dependent impairment in inflammation resolution. Transcriptional and protein biomarkers of disease severity differed with age, with the oldest adults exhibiting greater expression of pro-inflammatory genes and proteins in severe disease. Together, our study finds that aging is associated with impaired viral clearance, dysregulated immune signaling, and persistent and potentially pathologic activation of pro-inflammatory genes and proteins.
The IMPACC cohort, composed of >1,000 hospitalized COVID-19 participants, contains five illness trajectory groups (TGs) during acute infection (first 28 days), ranging from milder (TG1–3) to more ...severe disease course (TG4) and death (TG5). Here, we report deep immunophenotyping, profiling of >15,000 longitudinal blood and nasal samples from 540 participants of the IMPACC cohort, using 14 distinct assays. These unbiased analyses identify cellular and molecular signatures present within 72 h of hospital admission that distinguish moderate from severe and fatal COVID-19 disease. Importantly, cellular and molecular states also distinguish participants with more severe disease that recover or stabilize within 28 days from those that progress to fatal outcomes (TG4 vs. TG5). Furthermore, our longitudinal design reveals that these biologic states display distinct temporal patterns associated with clinical outcomes. Characterizing host immune responses in relation to heterogeneity in disease course may inform clinical prognosis and opportunities for intervention.
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•Distinct baseline and temporal patterns are associated with the clinical course•Persistent viral levels, despite high antibody titers, are associated with severity•Severity is linked to reduced cytotoxic NK cells, increased inflammation, and thrombosis•Myocardial damage markers distinguish critical patients who recover from those who die
Diray-Arce et al. conduct deep immunophenotyping of acute COVID-19 infection using more than 15,000 longitudinal samples from 540 hospitalized patients in the IMPACC cohort. The study comprehensively defines baseline and longitudinal immunologic states that are associated with mild to fatal disease trajectory groups.
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