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1.
Allergy Asthma Proc ; 43(5): 419-430, 2022 Sep 01.
Article in English | MEDLINE | ID: covidwho-2022489

ABSTRACT

Background: Secretory immunoglobulin A (sIgA) plays an important role in antiviral protective immunity. Although salivary testing has been used for many viral infections, including severe acute respiratory syndrome (SARS) and Middle East Respiratory Syndrome (MERS), its use has not yet been well established with the SARS coronavirus 2 (SARS-CoV-2). Quantification of salivary IgA and IgG antibodies can elucidate mucosal and systemic immune responses after natural infection or vaccination. Here, we report the development and validation of a rapid enzyme-linked immunosorbent assay (ELISA) for anti-SARS-CoV-2 salivary IgA and serum IgG antibodies, and present quantitative results for immunized subjects both prior to or following COVID-19 infections. Objective: Total and serum SARS-CoV-2 spike-specific IgG responses were compared with salivary spike-specific IgA and IgG responses in samples obtained from patients recently infected with SARS-CoV-2 and from subjects recently immunized with COVID-19 vaccines. Methods: A total of 52 paired saliva and serum samples were collected from 26 study participants: 7 subjects after COVID-19 infection and 19 subjects who were uninfected. The ELISA results from these samples were compared with five prepandemic control serum samples. Total IgG and SARS-CoV-2 spike-specific IgG in the serum samples from the subjects who were infected and vaccinated were also measured in a commercial laboratory with an enzyme immunoassay. Results: A wide variation in antibody responses was seen in salivary and serum samples measured by both methods. Three groups of serum total and IgG spike-specific SARS-CoV-2 antibody responses were observed: (1) low, (2) intermediate, and (3) high antibody responders. A correlational analysis of salivary IgA (sIgA) responses with serum IgG concentrations showed a statistical correlation in the low and intermediate antibody responder groups but not in the high group (which we believe was a result of saturation). Conclusion: These preliminary findings suggest measuring salivary and serum IgG and IgA merit further investigation as markers of current or recent SARS-CoV-2 infections.


Subject(s)
COVID-19 Vaccines , COVID-19 , Immunoglobulin A , Immunoglobulin G , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Antibodies, Viral , COVID-19/blood , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Humans , Immunization , Immunoglobulin A/analysis , Immunoglobulin A/blood , Immunoglobulin A/immunology , Immunoglobulin A, Secretory , Immunoglobulin G/analysis , Immunoglobulin G/blood , Immunoglobulin G/immunology , Saliva/chemistry , Saliva/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccination
2.
Nature ; 611(7934): 139-147, 2022 11.
Article in English | MEDLINE | ID: covidwho-2016757

ABSTRACT

Severe SARS-CoV-2 infection1 has been associated with highly inflammatory immune activation since the earliest days of the COVID-19 pandemic2-5. More recently, these responses have been associated with the emergence of self-reactive antibodies with pathologic potential6-10, although their origins and resolution have remained unclear11. Previously, we and others have identified extrafollicular B cell activation, a pathway associated with the formation of new autoreactive antibodies in chronic autoimmunity12,13, as a dominant feature of severe and critical COVID-19 (refs. 14-18). Here, using single-cell B cell repertoire analysis of patients with mild and severe disease, we identify the expansion of a naive-derived, low-mutation IgG1 population of antibody-secreting cells (ASCs) reflecting features of low selective pressure. These features correlate with progressive, broad, clinically relevant autoreactivity, particularly directed against nuclear antigens and carbamylated proteins, emerging 10-15 days after the onset of symptoms. Detailed analysis of the low-selection compartment shows a high frequency of clonotypes specific for both SARS-CoV-2 and autoantigens, including pathogenic autoantibodies against the glomerular basement membrane. We further identify the contraction of this pathway on recovery, re-establishment of tolerance standards and concomitant loss of acute-derived ASCs irrespective of antigen specificity. However, serological autoreactivity persists in a subset of patients with postacute sequelae, raising important questions as to the contribution of emerging autoreactivity to continuing symptomology on recovery. In summary, this study demonstrates the origins, breadth and resolution of autoreactivity in severe COVID-19, with implications for early intervention and the treatment of patients with post-COVID sequelae.


Subject(s)
Autoantibodies , B-Lymphocytes , COVID-19 , Humans , Autoantibodies/immunology , B-Lymphocytes/immunology , B-Lymphocytes/pathology , COVID-19/immunology , COVID-19/pathology , COVID-19/physiopathology , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Immunoglobulin G/immunology , Single-Cell Analysis , Autoantigens/immunology , Basement Membrane/immunology
3.
Fukushima J Med Sci ; 68(1): 67-70, 2022 Apr 08.
Article in English | MEDLINE | ID: covidwho-1975228

ABSTRACT

This study investigated the immune response and outcome of BNT162b2 vaccination among 12 staff at a hospital in Fukushima, Japan. Blood samples were collected from participants before their first vaccination, with subsequent sampling performed during the participants' work days for six weeks thereafter. Antibody titers peaked 6-13 days after the second vaccination (days 27-34 after the first), followed by a steady decrease. Six males had significantly lower peak antibody titers than six females (p = 0.016 with t-test); the older six (median age 53 years) had lower antibody titers than the younger six (median age 35 years) but without statistical significance (p value=0.24 with t-test).


Subject(s)
Antibodies, Viral , BNT162 Vaccine , COVID-19 , Immunoglobulin G , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Adult , Antibodies, Viral/immunology , BNT162 Vaccine/administration & dosage , BNT162 Vaccine/immunology , COVID-19/prevention & control , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/immunology , Female , Humans , Immunoglobulin G/immunology , Male , Middle Aged , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology
4.
Viruses ; 12(1)2020 01 20.
Article in English | MEDLINE | ID: covidwho-1969491

ABSTRACT

Middle East respiratory syndrome (MERS) is an acute, high-mortality-rate, severe infectious disease caused by an emerging MERS coronavirus (MERS-CoV) that causes severe respiratory diseases. The continuous spread and great pandemic potential of MERS-CoV make it necessarily important to develop effective vaccines. We previously demonstrated that the application of Gram-positive enhancer matrix (GEM) particles as a bacterial vector displaying the MERS-CoV receptor-binding domain (RBD) is a very promising MERS vaccine candidate that is capable of producing potential neutralization antibodies. We have also used the rabies virus (RV) as a viral vector to design a recombinant vaccine by expressing the MERS-CoV S1 (spike) protein on the surface of the RV. In this study, we compared the immunological efficacy of the vaccine candidates in BALB/c mice in terms of the levels of humoral and cellular immune responses. The results show that the rabies virus vector-based vaccine can induce remarkably earlier antibody response and higher levels of cellular immunity than the GEM particles vector. However, the GEM particles vector-based vaccine candidate can induce remarkably higher antibody response, even at a very low dose of 1 µg. These results indicate that vaccines constructed using different vaccine vector platforms for the same pathogen have different rates and trends in humoral and cellular immune responses in the same animal model. This discovery not only provides more alternative vaccine development platforms for MERS-CoV vaccine development, but also provides a theoretical basis for our future selection of vaccine vector platforms for other specific pathogens.


Subject(s)
Coronavirus Infections/immunology , Middle East Respiratory Syndrome Coronavirus/immunology , Viral Vaccines/immunology , Animals , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , Cell Line , Coronavirus Infections/prevention & control , Genetic Vectors , Humans , Immunization , Immunoglobulin G/blood , Immunoglobulin G/immunology , Lactococcus lactis/genetics , Mice , Mice, Inbred BALB C , Middle East Respiratory Syndrome Coronavirus/genetics , Rabies virus/genetics , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , T-Lymphocytes/immunology , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/immunology , Viral Vaccines/administration & dosage
5.
PLoS One ; 17(2): e0262591, 2022.
Article in English | MEDLINE | ID: covidwho-1968842

ABSTRACT

SARS-CoV-2 Nucleocapsid (N) is the most abundant viral protein expressed in host samples and is an important antigen for diagnosis. N is a 45 kDa protein that does not present disulfide bonds. Intending to avoid non-specific binding of SARS-CoV-2 N to antibodies from patients who previously had different coronaviruses, a 35 kDa fragment of N was expressed without a conserved motif in E. coli as inclusion bodies (N122-419-IB). Culture media and IB washing conditions were chosen to obtain N122-419-IB with high yield (370 mg/L bacterial culture) and protein purity (90%). High pressure solubilizes protein aggregates by weakening hydrophobic and ionic interactions and alkaline pH promotes solubilization by electrostatic repulsion. The association of pH 9.0 and 2.4 kbar promoted efficient solubilization of N122-419-IB without loss of native-like tertiary structure that N presents in IB. N122-419 was refolded with a yield of 85% (326 mg/L culture) and 95% purity. The refolding process takes only 2 hours and the protein is ready for use after pH adjustment, avoiding the necessity of dialysis or purification. Antibody binding of COVID-19-positive patients sera to N122-419 was confirmed by Western blotting. ELISA using N122-419 is effective in distinguishing between sera presenting antibodies against SARS-CoV-2 from those who do not. To the best of our knowledge, the proposed condition for IB solubilization is one of the mildest described. It is possible that the refolding process can be extended to a wide range of proteins with high yields and purity, even those that are sensible to very alkaline pH.


Subject(s)
Antibodies, Viral/blood , Antigens, Viral/chemistry , COVID-19/blood , COVID-19/diagnosis , Coronavirus Nucleocapsid Proteins/chemistry , Immunoglobulin G/blood , Inclusion Bodies/chemistry , Protein Refolding , SARS-CoV-2/immunology , Antibodies, Viral/immunology , Antigens, Viral/immunology , COVID-19/virology , Coronavirus Nucleocapsid Proteins/immunology , Enzyme-Linked Immunosorbent Assay/methods , Escherichia coli/genetics , Escherichia coli/metabolism , Humans , Hydrogen-Ion Concentration , Hydrostatic Pressure , Immunoglobulin G/immunology , Phosphoproteins/chemistry , Phosphoproteins/immunology , Protein Structure, Tertiary , Recombinant Proteins/chemistry , Recombinant Proteins/immunology , Solubility
6.
Proc Natl Acad Sci U S A ; 119(31): e2204336119, 2022 08 02.
Article in English | MEDLINE | ID: covidwho-1947765

ABSTRACT

The durability of vaccine-mediated immunity to SARS-CoV-2, the durations to breakthrough infection, and the optimal timings of booster vaccination are crucial knowledge for pandemic response. Here, we applied comparative evolutionary analyses to estimate the durability of immunity and the likelihood of breakthrough infections over time following vaccination by BNT162b2 (Pfizer-BioNTech), mRNA-1273 (Moderna), ChAdOx1 (Oxford-AstraZeneca), and Ad26.COV2.S (Johnson & Johnson/Janssen). We evaluated anti-Spike (S) immunoglobulin G (IgG) antibody levels elicited by each vaccine relative to natural infection. We estimated typical trajectories of waning and corresponding infection probabilities, providing the distribution of times to breakthrough infection for each vaccine under endemic conditions. Peak antibody levels elicited by messenger RNA (mRNA) vaccines mRNA-1273 and BNT1262b2 exceeded that of natural infection and are expected to typically yield more durable protection against breakthrough infections (median 29.6 mo; 5 to 95% quantiles 10.9 mo to 7.9 y) than natural infection (median 21.5 mo; 5 to 95% quantiles 3.5 mo to 7.1 y). Relative to mRNA-1273 and BNT1262b2, viral vector vaccines ChAdOx1 and Ad26.COV2.S exhibit similar peak anti-S IgG antibody responses to that from natural infection and are projected to yield lower, shorter-term protection against breakthrough infection (median 22.4 mo and 5 to 95% quantiles 4.3 mo to 7.2 y; and median 20.5 mo and 5 to 95% quantiles 2.6 mo to 7.0 y; respectively). These results leverage the tools from evolutionary biology to provide a quantitative basis for otherwise unknown parameters that are fundamental to public health policy decision-making.


Subject(s)
COVID-19 Vaccines , COVID-19 , Immunogenicity, Vaccine , SARS-CoV-2 , Antibodies, Viral/blood , Antibodies, Viral/immunology , Antibody Formation , COVID-19/immunology , COVID-19/prevention & control , COVID-19/virology , COVID-19 Vaccines/immunology , COVID-19 Vaccines/therapeutic use , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Time Factors
7.
PLoS One ; 17(3): e0265236, 2022.
Article in English | MEDLINE | ID: covidwho-1938430

ABSTRACT

OBJECTIVE: To determine the seroprevalence of the SARS Cov 2 infection among vaccine naive population in a rural district of South India post-second surge. METHODOLOGY: We conducted a cross-sectional study in the five villages of a randomly chosen sub-district in the Bangalore rural district. We did house to house surveys and recruited 831 vaccine naive adults in July 2021. We tested samples for the presence of antibodies (including IgG & IgM) to SARS CoV-2 using the Roche Elecsys SARS-CoV-2 -S assay that quantifies antibodies against the receptor-binding domain (RBD) of the spike (S) protein. RESULTS: We estimated an overall prevalence of 62.7% (95% CI: 59.3-66.0) and an age-and gender-adjusted seroprevalence of 44.9% (95% CI: 42.5-47.4). When adjusted for test performance, the seroprevalence was 74.64% (95% CI: 70.66-78.47). The case-to-undetected-infected ratio (CIR) was 1: 8.65 (95% CI 1:8.1-1:9.1), and the Infection Fatality Rate (IFR) was 16.27 per 100,00 infections as of 13 July 2021. A history of at least one symptom suggestive of COVID-19 or a positive COVID-19 test of self or a family member in the past were significantly associated with seropositivity. CONCLUSION: We report a high seroprevalence of COVID-19 infection despite the advantages of low population density and well-ventilated landscapes in rural areas. CIR and IFR were higher than the previous serosurvey conducted in the same population during the first surge. The thought of achieving herd immunity comes with relief. However, it's vital to put efforts into building population health and rural health infrastructure to avert future health catastrophes.


Subject(s)
COVID-19/epidemiology , COVID-19/immunology , SARS-CoV-2/immunology , Adult , Antibodies, Viral/immunology , COVID-19 Vaccines , Cross-Sectional Studies , Female , Humans , Immunoglobulin G/immunology , India/epidemiology , Male , Middle Aged , Prevalence , RNA, Viral/immunology , Rural Population , SARS-CoV-2/pathogenicity , Seroepidemiologic Studies
8.
PLoS One ; 17(2): e0253638, 2022.
Article in English | MEDLINE | ID: covidwho-1910476

ABSTRACT

Population immunity (herd immunity) to SARS-CoV-2 derives from two sources: vaccinations or cases of infection with the virus. Infections can be diagnosed as COVID-19 and registered, or they can be asymptomatic, oligosymptomatic, or even full-blown but undiagnosed and unregistered when patients recovered at home. Estimation of population immunity to SARS-CoV-2 is difficult and remains a subject of speculations. Here we present a population screening for SARS-CoV-2 specific IgG and IgA antibodies in Polish citizens (N = 501) who had never been positively diagnosed with or vaccinated against SARS-CoV-2. Serum samples were collected in Wroclaw (Lower Silesia) on 15th and 22nd May 2021. Sera from hospitalized COVID-19 patients (N = 22) or from vaccinated citizens (N = 14) served as positive controls. Sera were tested with Microblot-Array COVID-19 IgG and IgA (quantitative) that contain specific SARS-CoV-2 antigens: NCP, RBD, Spike S2, E, ACE2, PLPro protein, and antigens for exclusion cross-reactivity with other coronaviruses: MERS-CoV, SARS-CoV, HCoV 229E Np, HCoV NL63 Np. Within the investigated population of healthy individuals who had never been positively diagnosed with or vaccinated against SARS-CoV-2, we found that 35.5% (178 out of 501) were positive for SARS-CoV-2-specific IgG and 52.3% (262 out of 501) were positive for SARS-CoV-2-specific IgA; 21.2% of the investigated population developed virus-specific IgG or IgA while being asymptomatic. Anti-RBD IgG, which represents virus-neutralizing potential, was found in 25.6% of individuals (128 out of 501). These patients, though positive for anti-SARS-CoV-2 antibodies, cannot be identified in the public health system as convalescents due to undiagnosed infections, and they are considered unaffected by SARS-CoV-2. Their contribution to population immunity against COVID-19 should however be considered in predictions and modeling of the COVID-19 pandemic. Of note, the majority of the investigated population still lacked anti-RBD IgG protection (74.4%); thus vaccination against COVID-19 is still of the most importance for controlling the pandemic.


Subject(s)
Asymptomatic Infections/epidemiology , COVID-19 Vaccines/therapeutic use , COVID-19/epidemiology , COVID-19/immunology , Immunity, Herd , Pandemics/prevention & control , SARS-CoV-2/immunology , Vaccination/methods , Adolescent , Adult , Aged , Antibodies, Viral/blood , Antibodies, Viral/immunology , Antigens, Viral/immunology , COVID-19/blood , COVID-19/prevention & control , Cross Reactions , Female , Humans , Immunoglobulin A/blood , Immunoglobulin A/immunology , Immunoglobulin G/blood , Immunoglobulin G/immunology , Male , Middle Aged , Poland/epidemiology , Treatment Outcome , Young Adult
9.
Proc Natl Acad Sci U S A ; 119(28): e2204607119, 2022 07 12.
Article in English | MEDLINE | ID: covidwho-1908385

ABSTRACT

Messenger RNA (mRNA) vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are highly effective at inducing protective immunity. However, weak antibody responses are seen in some individuals, and cellular correlates of immunity remain poorly defined, especially for B cells. Here we used unbiased approaches to longitudinally dissect primary antibody, plasmablast, and memory B cell (MBC) responses to the two-dose mRNA-1273 vaccine in SARS-CoV-2-naive adults. Coordinated immunoglobulin A (IgA) and IgG antibody responses were preceded by bursts of spike-specific plasmablasts after both doses but earlier and more intensely after dose 2. While antibody and B cell cellular responses were generally robust, they also varied within the cohort and decreased over time after a dose-2 peak. Both antigen-nonspecific postvaccination plasmablast frequency after dose 1 and their spike-specific counterparts early after dose 2 correlated with subsequent antibody levels. This correlation between early plasmablasts and antibodies remained for titers measured at 6 months after vaccination. Several distinct antigen-specific MBC populations emerged postvaccination with varying kinetics, including two MBC populations that correlated with 2- and 6-month antibody titers. Both were IgG-expressing MBCs: one less mature, appearing as a correlate after the first dose, while the other MBC correlate showed a more mature and resting phenotype, emerging as a correlate later after dose 2. This latter MBC was also a major contributor to the sustained spike-specific MBC response observed at month 6. Thus, these plasmablasts and MBCs that emerged after both the first and second doses with distinct kinetics are potential determinants of the magnitude and durability of antibodies in response to mRNA-based vaccination.


Subject(s)
2019-nCoV Vaccine mRNA-1273 , Antibody Formation , B-Lymphocytes , COVID-19 , RNA, Messenger , SARS-CoV-2 , 2019-nCoV Vaccine mRNA-1273/administration & dosage , 2019-nCoV Vaccine mRNA-1273/immunology , B-Lymphocytes/immunology , COVID-19/prevention & control , Humans , Immunity, Cellular , Immunoglobulin A/blood , Immunoglobulin A/immunology , Immunoglobulin G/blood , Immunoglobulin G/immunology , RNA, Messenger/administration & dosage , RNA, Messenger/immunology , SARS-CoV-2/immunology , Vaccination
10.
Sci Rep ; 12(1): 3351, 2022 03 01.
Article in English | MEDLINE | ID: covidwho-1908222

ABSTRACT

Severe acute respiratory coronavirus 2 (SARS-CoV-2) has spread globally since its emergence in 2019. Most SARS-CoV-2 infections generate immune responses leading to rising levels of immunoglobulins (Ig) M, A and G which can be detected using diagnostic tests including enzyme-linked immunosorbent assays (ELISA). Whilst implying previous SARS-CoV-2 infection, the detection of Ig by ELISA does not guarantee the presence of neutralising antibodies (NAb) that can prevent the virus infecting cells. Plaque reduction neutralisation tests (PRNT) detect NAb, but are not amenable to mass testing as they take several days and require use of SARS-CoV-2 in high biocontainment laboratories. We evaluated the ability of IgG and IgM ELISAs targeting SARS-CoV-2 spike subunit 1 receptor binding domain (S1-RBD), and spike subunit 2 (S2) and nucleocapsid protein (NP), at predicting the presence and magnitude of NAb determined by PRNT. IgG S2 + NP ELISA was 96.8% [95% CI 83.8-99.9] sensitive and 88.9% [95% CI 51.8-99.7] specific at predicting the presence of NAbs (PRNT80 > 1:40). IgG and IgM S1-RBD ELISAs correlated with PRNT titre, with higher ELISA results increasing the likelihood of a robust neutralising response. The IgM S1-RBD assay can be used as a rapid, high throughput test to approximate the magnitude of NAb titre.


Subject(s)
Antibodies, Viral/immunology , COVID-19/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Neutralization Tests , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Aged , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Middle Aged
11.
J Virol ; 96(13): e0014322, 2022 Jul 13.
Article in English | MEDLINE | ID: covidwho-1879115

ABSTRACT

Differentiation of infected from vaccinated hosts (DIVH) is a critical step in virus eradication programs. DIVH-compatible vaccines, however, take years to develop, and are therefore unavailable for fighting the sudden outbreaks that typically drive pandemics. Here, we establish a protocol for the swift and efficient development of DIVH assays, and show that this approach is compatible with any type of vaccines. Using porcine circovirus 2 (PCV2) as the experimental model, the first step is to use Immunoglobin G (IgG) sero-dynamics (IsD) curves to aid epitope discovery (IsDAED): PCV2 Cap peptides were categorized into three types: null interaction, nonspecific interaction (NSI), and specific interaction (SI). We subsequently compared IsDAED approach and traditional approach, and demonstrated identifying SI peptides and excluding NSI peptides supports efficient diagnostic kit development, specifically using a protein-peptide hybrid microarray (PPHM). IsDAED directed the design of a DIVH protocol for three types of PCV2 vaccines (while using a single PPHM). Finally, the DIVH protocol successfully differentiated infected pigs from vaccinated pigs at five farms. This IsDAED approach is almost certainly extendable to other viruses and host species. IMPORTANCE Sudden outbreaks of pandemics caused by virus, such as SARS-CoV-2, has been determined as a public health emergency of international concern. However, the development of a DIVH-compatible vaccine is time-consuming and full of uncertainty, which is unsuitable for an emergent situation like the ongoing COVID-19 pandemic. Along with the development and public health implementation of new vaccines to prevent human diseases, e.g., human papillomavirus vaccines for cervical cancer; enterovirus 71 vaccines for hand, foot, and mouth disease; and most recently SARS-CoV-2, there is an increasing demand for DIVH. Here, we use the IsDAED approach to confirm SI peptides and to exclude NSI peptides, finally to direct the design of a DIVH protocol. It is plausible that our IsDAED approach is applicable for other infectious disease.


Subject(s)
Antibodies, Viral , Circoviridae Infections , Epitopes , Immunoglobulin G , Viral Vaccines , Animals , Antibodies, Viral/blood , COVID-19 , Circoviridae Infections/immunology , Circovirus , Disease Models, Animal , Epitopes/analysis , Epitopes/immunology , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Peptides , SARS-CoV-2 , Swine , Swine Diseases/immunology , Viral Vaccines/immunology
12.
Br J Haematol ; 198(4): 668-679, 2022 08.
Article in English | MEDLINE | ID: covidwho-1874397

ABSTRACT

Allogeneic haematopoietic stem cell transplant (HSCT) recipients remain at high risk of adverse outcomes from coronavirus disease 2019 (COVID-19) and emerging variants. The optimal prophylactic vaccine strategy for this cohort is not defined. T cell-mediated immunity is a critical component of graft-versus-tumour effect and in determining vaccine immunogenicity. Using validated anti-spike (S) immunoglobulin G (IgG) and S-specific interferon-gamma enzyme-linked immunospot (IFNγ-ELIspot) assays we analysed response to a two-dose vaccination schedule (either BNT162b2 or ChAdOx1) in 33 HSCT recipients at ≤2 years from transplant, alongside vaccine-matched healthy controls (HCs). After two vaccines, infection-naïve HSCT recipients had a significantly lower rate of seroconversion compared to infection-naïve HCs (25/32 HSCT vs. 39/39 HCs no responders) and had lower S-specific T-cell responses. The HSCT recipients who received BNT162b2 had a higher rate of seroconversion compared to ChAdOx1 (89% vs. 74%) and significantly higher anti-S IgG titres (p = 0.022). S-specific T-cell responses were seen after one vaccine in HCs and HSCT recipients. However, two vaccines enhanced S-specific T-cell responses in HCs but not in the majority of HSCT recipients. These data demonstrate limited immunogenicity of two-dose vaccination strategies in HSCT recipients, bolstering evidence of the need for additional boosters and/or alternative prophylactic measures in this group.


Subject(s)
COVID-19 Vaccines , COVID-19 , Hematopoietic Stem Cell Transplantation , Age Factors , Antibodies, Viral/immunology , BNT162 Vaccine/immunology , BNT162 Vaccine/therapeutic use , Bone Marrow Transplantation/adverse effects , COVID-19/prevention & control , COVID-19/virology , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , COVID-19 Vaccines/pharmacology , COVID-19 Vaccines/therapeutic use , ChAdOx1 nCoV-19/immunology , ChAdOx1 nCoV-19/therapeutic use , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Immunity, Cellular/drug effects , Immunity, Cellular/immunology , Immunity, Humoral/drug effects , Immunity, Humoral/immunology , Immunoglobulin G/blood , Immunoglobulin G/immunology , Seroconversion , Transplantation, Homologous/adverse effects , Vaccination/adverse effects
13.
Sci Rep ; 12(1): 8890, 2022 05 25.
Article in English | MEDLINE | ID: covidwho-1864769

ABSTRACT

We assessed the feasibility of a highly sensitive immunoassay method based on single molecule array (Simoa) technology to detect IgG and IgA antibodies against SARS-CoV-2 spike protein receptor binding domain (RBD) in saliva from individuals with natural or vaccine-induced COVID-19 immunity. The performance of the method was compared to a laboratory-developed SARS-CoV-2 RBD total antibody enzyme-linked immunosorbent assay (ELISA). Paired serum and saliva specimens were collected from individuals (n = 40) prior to and 2 weeks after receiving an initial prime COVID-19 vaccine dose (Pfizer/BioNTech BNT162b2 or Moderna mRNA-1273). Saliva was collected using a commercially available collection device (OraSure Inc.) and SARS-CoV-2 RBD IgG antibodies were measured by an indirect ELISA using concentrated saliva samples and a Simoa immunoassay using unconcentrated saliva samples. The IgG results were compared with paired serum specimens that were analyzed for total RBD antibodies using the ELISA method. The analytical sensitivity of the saliva-based Simoa immunoassay was five orders of magnitude higher than the ELISA assay: 0.24 pg/mL compared to 15 ng/mL. The diagnostic sensitivity of the saliva ELISA method was 90% (95% CI 76.3-97.2%) compared to 91.7% (95% CI 77.5-98.2%) for the Simoa immunoassay without total IgG-normalization and 100% (95% CI 90.3-100%) for the Simoa immunoassay after total IgG-normalization when compared to the serum ELISA assay. When analyzed using the SARS-CoV-2 RBD IgG antibody ELISA, the average relative increase in antibody index (AI) between the saliva of the post- and pre-vaccinated individuals was 8.7 (AIpost/pre). An average relative increase of 431 pg/mL was observed when the unconcentrated saliva specimens were analyzed using the Simoa immunoassay (SARS-CoV-2 RBD IgGpost/pre). These findings support the suitability of concentrated saliva specimens for the measurement of SARS-CoV-2 RBD IgG antibodies via ELISA, and unconcentrated saliva specimens for the measurement of SARS-CoV-2 RBD IgG and IgA using an ultrasensitive Simoa immunoassay.


Subject(s)
COVID-19 Vaccines , COVID-19 , Immunoglobulin G , SARS-CoV-2 , Antibodies, Viral/chemistry , Antibodies, Viral/immunology , BNT162 Vaccine , COVID-19/diagnosis , COVID-19/immunology , COVID-19 Vaccines/immunology , Humans , Immunoglobulin A/chemistry , Immunoglobulin A/immunology , Immunoglobulin G/chemistry , Immunoglobulin G/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology
14.
PLoS One ; 17(2): e0262442, 2022.
Article in English | MEDLINE | ID: covidwho-1854992

ABSTRACT

In late December 2019, pneumonia cases of unknown origin were reported in Wuhan, China. This virus was named SARS-CoV2 and the clinical syndrome was named coronavirus disease 19 (COVID-19). South Africa, despite strict and early lockdown has the highest infection rate in Africa. A key component of South Africa's response to SARSCoV2 was the rapid scale-up of diagnostic testing. The Abbott SARS-CoV2 assay detects IgG antibodies against the Nucleocapsid (N) protein of the SARS-CoV2 virus. This study undertook to validate and evaluate performance criteria of the Abbott assay and to establish whether this assay would show clinical utility in our population. Positive patients (n = 391) and negative controls (n = 139) were included. The Architect-i and Alinity-i systems were analyzers that were used to perform the SARS-CoV-2 IgG assay. In-house ELISA was incorporated into the study as a confirmatory serology test. A total of number of 530 participants was tested, 87% were symptomatic with infection and 13% were asymptomatic. When compared to RT-qPCR, the sensitivity of Architect and Alinity SARS-CoV2 assays was 69.5% and 64.8%, respectively. Specificity for Architect and Alinity assays was 95% and 90.3%, respectively. The Abbott assay was also compared to in house ELISA assay, with sensitivity for the Architect and Alinity assays of 94.7% and 92.5%, respectively. Specificity for Abbott Alinity assays was 91.7% higher than Abbott Architect 88.1%. Based on the current findings testing of IgG after 14 days is recommended in South Africa and supports other studies performed around the world.


Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing/methods , COVID-19/diagnosis , Immunoglobulin G/blood , SARS-CoV-2/isolation & purification , Adult , Aged , Aged, 80 and over , Antibodies, Viral/immunology , COVID-19/blood , COVID-19/epidemiology , COVID-19/virology , Enzyme-Linked Immunosorbent Assay , Female , Follow-Up Studies , Humans , Immunoglobulin G/immunology , Male , Middle Aged , Prognosis , Retrospective Studies , South Africa/epidemiology , Young Adult
15.
EBioMedicine ; 75: 103805, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1850947

ABSTRACT

BACKGROUND: Two doses of mRNA vaccination have shown >94% efficacy at preventing COVID-19 mostly in naïve adults, but it is not clear if the second dose is needed to maximize effectiveness in those previously exposed to SARS-CoV-2 and what other factors affect responsiveness. METHODS: We measured IgA, IgG and IgM levels against SARS-CoV-2 spike (S) and nucleocapsid (N) antigens from the wild-type and S from the Alpha, Beta and Gamma variants of concern, after BNT162b2 (Pfizer/BioNTech) or mRNA-1273 (Moderna) vaccination in a cohort of health care workers (N=578). Neutralizing capacity and antibody avidity were evaluated. Data were analyzed in relation to COVID-19 history, comorbidities, vaccine doses, brand and adverse events. FINDINGS: Vaccination induced robust IgA and IgG levels against all S antigens. Neutralization capacity and S IgA and IgG levels were higher in mRNA-1273 vaccinees, previously SARS-CoV-2 exposed, particularly if symptomatic, and in those experiencing systemic adverse effects (p<0·05). A second dose in pre-exposed did not increase antibody levels. Smoking and comorbidities were associated with 43% (95% CI, 19-59) and 45% (95% CI, 63-18) lower neutralization, respectively, and 35% (95% CI, 3-57%) and 55% (95% CI, 33-70%) lower antibody levels, respectively. Among fully vaccinated, 6·3% breakthroughs were detected up to 189 days post-vaccination. Among pre-exposed non-vaccinated, 90% were IgG seropositive more than 300 days post-infection. INTERPRETATION: Our data support administering a single-dose in pre-exposed healthy individuals as primary vaccination. However, heterogeneity of responses suggests that personalized recommendations may be necessary depending on COVID-19 history and life-style. Higher mRNA-1273 immunogenicity would be beneficial for those expected to respond worse to vaccination and in face of variants that escape immunity such as Omicron. Persistence of antibody levels in pre-exposed unvaccinated indicates maintenance of immunity up to one year. FUNDING: This work was supported by Institut de Salut Global de Barcelona (ISGlobal) internal funds, in-kind contributions from Hospital Clínic de Barcelona, the Fundació Privada Daniel Bravo Andreu, and European Institute of Innovation and Technology (EIT) Health (grant number 20877), supported by the European Institute of Innovation and Technology, a body of the European Union receiving support from the H2020 Research and Innovation Programme. We acknowledge support from the Spanish Ministry of Science and Innovation and State Research Agency through the "Centro de Excelencia Severo Ochoa 2019-2023" Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Program. L. I. work was supported by PID2019-110810RB-I00 grant from the Spanish Ministry of Science & Innovation. Development of SARS-CoV-2 reagents was partially supported by the National Institute of Allergy and Infectious Diseases Centers of Excellence for Influenza Research and Surveillance (contract number HHSN272201400008C). The funders had no role in study design, data collection and analysis, the decision to publish, or the preparation of the manuscript.


Subject(s)
/administration & dosage , Antibody Formation/drug effects , COVID-19/prevention & control , Health Personnel , SARS-CoV-2/immunology , /immunology , Adult , Antibodies, Viral/immunology , COVID-19/epidemiology , COVID-19/immunology , Coronavirus Nucleocapsid Proteins/immunology , Female , Humans , Immunogenicity, Vaccine , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Male , Middle Aged , Phosphoproteins/immunology , Spike Glycoprotein, Coronavirus/immunology
16.
J Clin Immunol ; 42(2): 232-239, 2022 02.
Article in English | MEDLINE | ID: covidwho-1838372

ABSTRACT

PURPOSE: To study the effect of interferon-α2 auto-antibodies (IFN-α2 Abs) on clinical and virological outcomes in critically ill COVID-19 patients and the risk of IFN-α2 Abs transfer during convalescent plasma treatment. METHODS: Sera from healthy controls, cases of COVID-19, and other respiratory illness were tested for IFN-α2 Abs by ELISA and a pseudo virus-based neutralization assay. The effects of disease severity, sex, and age on the risk of having neutralizing IFN-α2 Abs were determined. Longitudinal analyses were performed to determine association between IFN-α2 Abs and survival and viral load and whether serum IFN-α2 Abs appeared after convalescent plasma transfusion. RESULTS: IFN-α2 neutralizing sera were found only in COVID-19 patients, with proportions increasing with disease severity and age. In the acute stage of COVID-19, all sera from patients with ELISA-detected IFN-α2 Abs (13/164, 7.9%) neutralized levels of IFN-α2 exceeding physiological concentrations found in human plasma and this was associated with delayed viral clearance. Convalescent plasma donors that were anti-IFN-α2 ELISA positive (3/118, 2.5%) did not neutralize the same levels of IFN-α2. Neutralizing serum IFN-α2 Abs were associated with delayed viral clearance from the respiratory tract. CONCLUSIONS: IFN-α2 Abs were detected by ELISA and neutralization assay in COVID-19 patients, but not in ICU patients with other respiratory illnesses. The presence of neutralizing IFN-α2 Abs in critically ill COVID-19 is associated with delayed viral clearance. IFN-α2 Abs in COVID-19 convalescent plasma donors were not neutralizing in the conditions tested.


Subject(s)
Autoantibodies/immunology , COVID-19/immunology , COVID-19/therapy , Interferon alpha-2/immunology , Plasma/immunology , Adult , Aged , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Antiviral Agents/immunology , Blood Component Transfusion/methods , Critical Illness , Female , Humans , Immunization, Passive/methods , Immunoglobulin G/immunology , Male , Middle Aged , SARS-CoV-2/immunology
17.
Lancet ; 399(10324): 521-529, 2022 02 05.
Article in English | MEDLINE | ID: covidwho-1815310

ABSTRACT

INTRODUCTION: The inactivated whole-virion SARS-CoV-2 vaccine (CoronaVac, Sinovac) has been widely used in a two-dose schedule. We assessed whether a third dose of the homologous or a different vaccine could boost immune responses. METHODS: RHH-001 is a phase 4, participant masked, two centre, safety and immunogenicity study of Brazilian adults (18 years and older) in São Paulo or Salvador who had received two doses of CoronaVac 6 months previously. The third heterologous dose was of either a recombinant adenoviral vectored vaccine (Ad26.COV2-S, Janssen), an mRNA vaccine (BNT162b2, Pfizer-BioNTech), or a recombinant adenoviral-vectored ChAdOx1 nCoV-19 vaccine (AZD1222, AstraZeneca), compared with a third homologous dose of CoronaVac. Participants were randomly assigned (5:6:5:5) by a RedCAP computer randomisation system stratified by site, age group (18-60 years or 61 years and over), and day of randomisation, with a block size of 42. The primary outcome was non-inferiority of anti-spike IgG antibodies 28 days after the booster dose in the heterologous boost groups compared with homologous regimen, using a non-inferiority margin for the geometric mean ratio (heterologous vs homologous) of 0·67. Secondary outcomes included neutralising antibody titres at day 28, local and systemic reactogenicity profiles, adverse events, and serious adverse events. This study was registered with Registro Brasileiro de Ensaios Clínicos, number RBR-9nn3scw. FINDINGS: Between Aug 16, and Sept 1, 2021, 1240 participants were randomly assigned to one of the four groups, of whom 1239 were vaccinated and 1205 were eligible for inclusion in the primary analysis. Antibody concentrations were low before administration of a booster dose with detectable neutralising antibodies of 20·4% (95% CI 12·8-30·1) in adults aged 18-60 years and 8·9% (4·2-16·2) in adults 61 years or older. From baseline to day 28 after the booster vaccine, all groups had a substantial rise in IgG antibody concentrations: the geometric fold-rise was 77 (95% CI 67-88) for Ad26.COV2-S, 152 (134-173) for BNT162b2, 90 (77-104) for ChAdOx1 nCoV-19, and 12 (11-14) for CoronaVac. All heterologous regimens had anti-spike IgG responses at day 28 that were superior to homologous booster responses: geometric mean ratios (heterologous vs homologous) were 6·7 (95% CI 5·8-7·7) for Ad26.COV2-S, 13·4 (11·6-15·3) for BNT162b2, and 7·0 (6·1-8·1) for ChAdOx1 nCoV-19. All heterologous boost regimens induced high concentrations of pseudovirus neutralising antibodies. At day 28, all groups except for the homologous boost in the older adults reached 100% seropositivity: geometric mean ratios (heterologous vs homologous) were 8·7 (95% CI 5·9-12·9) for Ad26.COV2-S vaccine, 21·5 (14·5-31·9) for BNT162b2, and 10·6 (7·2-15·6) for ChAdOx1 nCoV-19. Live virus neutralising antibodies were also boosted against delta (B.1.617.2) and omicron variants (B.1.1.529). There were five serious adverse events. Three of which were considered possibly related to the vaccine received: one in the BNT162b2 group and two in the Ad26.COV2-S group. All participants recovered and were discharged home. INTERPRETATION: Antibody concentrations were low at 6 months after previous immunisation with two doses of CoronaVac. However, all four vaccines administered as a third dose induced a significant increase in binding and neutralising antibodies, which could improve protection against infection. Heterologous boosting resulted in more robust immune responses than homologous boosting and might enhance protection. FUNDING: Ministry of Health, Brazil.


Subject(s)
COVID-19 Vaccines , COVID-19/prevention & control , Adult , Aged , Antibodies, Neutralizing , Antibodies, Viral , Brazil , Female , Humans , Immunization, Secondary , Immunoglobulin G/immunology , Male , Middle Aged , SARS-CoV-2 , Single-Blind Method , Vaccines, Inactivated
18.
J Virol ; 96(4): e0160021, 2022 02 23.
Article in English | MEDLINE | ID: covidwho-1759291

ABSTRACT

A comprehensive study of the B cell response against SARS-CoV-2 could be significant for understanding the immune response and developing therapeutical antibodies and vaccines. To define the dynamics and characteristics of the antibody repertoire following SARS-CoV-2 infection, we analyzed the mRNA transcripts of immunoglobulin heavy chain (IgH) repertoires of 24 peripheral blood samples collected between 3 and 111 days after symptom onset from 10 COVID-19 patients. Massive clonal expansion of naive B cells with limited somatic hypermutation (SHM) was observed in the second week after symptom onset. The proportion of low-SHM IgG clones strongly correlated with spike-specific IgG antibody titers, highlighting the significant activation of naive B cells in response to a novel virus infection. The antibody isotype switching landscape showed a transient IgA surge in the first week after symptom onset, followed by a sustained IgG elevation that lasted for at least 3 months. SARS-CoV-2 infection elicited poly-germ line reactive antibody responses. Interestingly, 17 different IGHV germ line genes recombined with IGHJ6 showed significant clonal expansion. By comparing the IgH repertoires that we sequenced with the 774 reported SARS-CoV-2-reactive monoclonal antibodies (MAbs), 13 shared spike-specific IgH clusters were found. These shared spike-specific IgH clusters are derived from the same lineage of several recently published neutralizing MAbs, including CC12.1, CC12.3, C102, REGN10977, and 4A8. Furthermore, identical spike-specific IgH sequences were found in different COVID-19 patients, suggesting a highly convergent antibody response to SARS-CoV-2. Our analysis based on sequencing antibody repertoires from different individuals revealed key signatures of the systemic B cell response induced by SARS-CoV-2 infection. IMPORTANCE Although the canonical delineation of serum antibody responses following SARS-CoV-2 infection has been well established, the dynamics of antibody repertoire at the mRNA transcriptional level has not been well understood, especially the correlation between serum antibody titers and the antibody mRNA transcripts. In this study, we analyzed the IgH transcripts and characterized the B cell clonal expansion and differentiation, isotype switching, and somatic hypermutation in COVID-19 patients. This study provided insights at the repertoire level for the B cell response after SARS-CoV-2 infection.


Subject(s)
Antibodies, Neutralizing/genetics , Antibodies, Viral/genetics , B-Lymphocytes/immunology , COVID-19/genetics , Immunoglobulin G/genetics , Receptors, Antigen, B-Cell/genetics , SARS-CoV-2/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , Humans , Immunoglobulin G/immunology , Receptors, Antigen, B-Cell/immunology
19.
Lancet Infect Dis ; 22(2): e52-e58, 2022 02.
Article in English | MEDLINE | ID: covidwho-1751515

ABSTRACT

As the number of individuals vaccinated against SARS-CoV-2 rises worldwide, population-level data regarding the vaccines' ability to reduce infection are being generated. Randomised trials have shown that these vaccines dramatically reduce symptomatic COVID-19; however, less is known about their effects on transmission between individuals. The natural course of infection with SARS-CoV-2 involves infection of the respiratory epithelia and replication within the mucosa to sufficient viral titres for transmission via aerosol particles and droplets. Here we discuss the available data on the existing, approved SARS-CoV-2 vaccines' capacity to reduce transmissibility by reducing primary infection, viral replication, capacity for transmission, and symptomaticity. The potential for mucosal-targeted SARS-CoV-2 vaccine strategies to more effectively limit transmission than intramuscular vaccines is considered with regard to known immunological mechanisms. Finally, we enumerate the population-level effects of approved vaccines on transmission through observational studies following clinical trials and vaccine distribution in real-world settings.


Subject(s)
COVID-19 Vaccines , COVID-19/prevention & control , COVID-19/transmission , Antibodies, Viral/biosynthesis , Antibodies, Viral/immunology , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , Humans , Immunoglobulin A/biosynthesis , Immunoglobulin A/immunology , Immunoglobulin G/biosynthesis , Immunoglobulin G/immunology , Virus Replication/immunology
20.
PLoS One ; 17(3): e0265016, 2022.
Article in English | MEDLINE | ID: covidwho-1745313

ABSTRACT

Serological databases represent an important source of information to perceive COVID-19 impact on health professionals involved in combating the disease. This paper describes SerumCovid, a COVID-19 serological database focused on the diagnosis of health professionals, providing a preliminary analysis to contribute to the understanding of the antibody response to the SARS-CoV-2. The study population comprises 321 samples from 236 healthcare and frontline workers fighting COVID-19 in Vitória de Santo Antão, Brazil. Samples were collected from at least six days of symptoms to more than 100 days. The used immunoenzymatic assays were Euroimmun Anti-SARS-CoV-2 ELISA IgG and IgA. The most common gender in SerumCovid is female, while the most common age group is between 30 and 39 years old. However, no statistical differences were observed in either genders or age categories. The most reported symptoms were fatigue, headaches, and myalgia. Still, some subjects presented positive results for IgA after 130 days. Based on a temporal analysis, we have not identified general patterns as subjects presented high and low values of IgA and IgG with different evolution trends. Unexpectedly, for subjects with both serological tests, the outcome of IgA and IgG tests were the same (either positive or negative) for more than 80% of the samples. Therefore, SerumCovid helps better understand how COVID-19 affected healthcare and frontline workers, which increases knowledge about the infection and enables direct prevention actions.


Subject(s)
COVID-19 Serological Testing , COVID-19/epidemiology , Health Personnel/statistics & numerical data , Adolescent , Adult , Antibodies, Viral/immunology , Brazil/epidemiology , COVID-19/diagnosis , COVID-19/immunology , COVID-19 Serological Testing/methods , COVID-19 Serological Testing/statistics & numerical data , Databases as Topic , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Male , Middle Aged , SARS-CoV-2/immunology , Young Adult
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