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1.
Clin Infect Dis ; 73(12): 2155-2162, 2021 12 16.
Article in English | MEDLINE | ID: covidwho-1592795

ABSTRACT

BACKGROUND: Assessing the duration of immunity following infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a first priority to gauge the degree of protection following infection. Such knowledge is lacking, especially in the general population. Here, we studied changes in immunoglobulin isotype seropositivity and immunoglobulin G (IgG) binding strength of SARS-CoV-2-specific serum antibodies up to 7 months following onset of symptoms in a nationwide sample. METHODS: Participants from a prospective representative serological study in the Netherlands were included based on IgG seroconversion to the spike S1 protein of SARS-CoV-2 (N = 353), with up to 3 consecutive serum samples per seroconverted participant (N = 738). Immunoglobulin M (IgM), immunoglobulin A (IgA), and IgG antibody concentrations to S1, and increase in IgG avidity in relation to time since onset of disease symptoms, were determined. RESULTS: While SARS-CoV-2-specific IgM and IgA antibodies declined rapidly after the first month after disease onset, specific IgG was still present in 92% (95% confidence interval [CI], 89%-95%) of the participants after 7 months. The estimated 2-fold decrease of IgG antibodies was 158 days (95% CI, 136-189 days). Concentrations were sustained better in persons reporting significant symptoms compared to asymptomatic persons or those with mild upper respiratory complaints only. Similarly, avidity of IgG antibodies for symptomatic persons showed a steeper increase over time compared with persons with mild or no symptoms (P = .022). CONCLUSIONS: SARS-CoV-2-specific IgG antibodies persist and show increasing avidity over time, indicative of underlying immune maturation. These data support development of immune memory against SARS-CoV-2, providing insight into protection of the general unvaccinated part of the population. CLINICAL TRIALS REGISTRATION: NL8473 (the Dutch trial registry).


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Netherlands/epidemiology , Prospective Studies
2.
Clin Infect Dis ; 73(11): e4082-e4089, 2021 12 06.
Article in English | MEDLINE | ID: covidwho-1559187

ABSTRACT

BACKGROUND: Leronlimab, a monoclonal antibody blocker of C-C chemokine receptor type 5 originally developed to treat human immunodeficiency virus infection, was administered as an open-label compassionate-use therapeutic for coronavirus disease 2019 (COVID-19). METHODS: Twenty-three hospitalized severe/critical COVID-19 patients received 700 mg leronlimab subcutaneously, repeated after 7 days in 17 of 23 patients still hospitalized. Eighteen of 23 received other experimental treatments, including convalescent plasma, hydroxychloroquine, steroids, and/or tocilizumab. Five of 23 received leronlimab after blinded, placebo-controlled trials of remdesivir, sarilumab, selinexor, or tocilizumab. Outcomes and results were extracted from medical records. RESULTS: Mean age was 69.5 ±â€…14.9 years; 20 had significant comorbidities. At baseline, 22 were receiving supplemental oxygen (3 high flow, 7 mechanical ventilation). Blood showed markedly elevated inflammatory markers (ferritin, D-dimer, C-reactive protein) and an elevated neutrophil-to-lymphocyte ratio. By day 30 after initial dosing, 17 were recovered, 2 were still hospitalized, and 4 had died. Of the 7 intubated at baseline, 4 were fully recovered off oxygen, 2 were still hospitalized, and 1 had died. CONCLUSIONS: Leronlimab appeared safe and well tolerated. The high recovery rate suggested benefit, and those with lower inflammatory markers had better outcomes. Some, but not all, patients appeared to have dramatic clinical responses, indicating that unknown factors may determine responsiveness to leronlimab. Routine inflammatory and cell prognostic markers did not markedly change immediately after treatment, although interleukin-6 tended to fall. In some persons, C-reactive protein clearly dropped only after the second leronlimab dose, suggesting that a higher loading dose might be more effective. Future controlled trials will be informative.


Subject(s)
COVID-19 , Aged , Aged, 80 and over , Antibodies, Monoclonal, Humanized , COVID-19/therapy , HIV Antibodies , Humans , Immunization, Passive , Middle Aged , SARS-CoV-2 , Treatment Outcome
3.
Clin Microbiol Infect ; 27(9): 1351.e5-1351.e7, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1379061

ABSTRACT

OBJECTIVES: Data on the immune response after two doses of BNT162b2 are so far limited. Previously infected individuals were excluded from pivotal clinical trials and the optimum dose regimen in this population has not been clearly studied. The CRO-VAX HCP study aims to investigate the early antibody response in a population of health-care professionals having received two doses of the BNT162b2 mRNA coronavirus disease 2019 (COVID-19) vaccine. METHODS: The CRO-VAX HCP study is a multicentre, prospective, interventional study conducted in several sites in Belgium. The study included 231 health-care professional volunteers who received the two-dose regimen of the BNT162b2 mRNA COVID-19 vaccine. Of these, 73 were previously infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and 158 were uninfected and seronegative. In the first group, blood samples were collected at baseline and after 2, 4, 7, 10, 14, 21 and 28 days. In the second group, samples were obtained at baseline and after 14 and 28 days. Antibodies against the SARS-CoV-2 nucleocapsid and the receptor binding domain of the S1 subunit of the spike protein were measured in all individuals at different time-points. RESULTS: In uninfected individuals, 95.5% (95% CI 91.0%-98.2%) developed anti-spike antibodies after 14 days and a 24.9-fold rise (95% CI 21.4%-28.9%) in antibody titre was observed after the second dose. In previously infected individuals, peak antibody response was reached after 7 days (i.e. 6347 U/mL) and the second dose did not lead to significantly higher antibody titres (i.e. 8856-11 911 U/mL). Antibody titres were higher in previously infected individuals. CONCLUSIONS: This study supports the concept that a single dose of BNT162b2 would be sufficient in previously infected individuals.


Subject(s)
Antibodies, Viral/blood , COVID-19 Vaccines/administration & dosage , COVID-19/epidemiology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Adult , Aged , Belgium , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Case-Control Studies , Drug Administration Schedule , Female , Health Personnel , Humans , Immunity, Humoral , Male , Middle Aged , Prospective Studies , Time Factors , Young Adult
4.
Sci Immunol ; 6(58)2021 04 15.
Article in English | MEDLINE | ID: covidwho-1349998

ABSTRACT

Novel mRNA vaccines for SARS-CoV-2 have been authorized for emergency use. Despite their efficacy in clinical trials, data on mRNA vaccine-induced immune responses are mostly limited to serological analyses. Here, we interrogated antibody and antigen-specific memory B cells over time in 33 SARS-CoV-2 naïve and 11 SARS-CoV-2 recovered subjects. SARS-CoV-2 naïve individuals required both vaccine doses for optimal increases in antibodies, particularly for neutralizing titers against the B.1.351 variant. Memory B cells specific for full-length spike protein and the spike receptor binding domain (RBD) were also efficiently primed by mRNA vaccination and detectable in all SARS-CoV-2 naive subjects after the second vaccine dose, though the memory B cell response declined slightly with age. In SARS-CoV-2 recovered individuals, antibody and memory B cell responses were significantly boosted after the first vaccine dose; however, there was no increase in circulating antibodies, neutralizing titers, or antigen-specific memory B cells after the second dose. This robust boosting after the first vaccine dose strongly correlated with levels of pre-existing memory B cells in recovered individuals, identifying a key role for memory B cells in mounting recall responses to SARS-CoV-2 antigens. Together, our data demonstrated robust serological and cellular priming by mRNA vaccines and revealed distinct responses based on prior SARS-CoV-2 exposure, whereby COVID-19 recovered subjects may only require a single vaccine dose to achieve peak antibody and memory B cell responses. These findings also highlight the utility of defining cellular responses in addition to serologies and may inform SARS-CoV-2 vaccine distribution in a resource-limited setting.


Subject(s)
Antibodies, Viral/immunology , B-Lymphocytes/immunology , COVID-19 Vaccines , COVID-19/immunology , SARS-CoV-2/immunology , Vaccines, Synthetic , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Female , Humans , Male , Middle Aged , RNA, Messenger , Spike Glycoprotein, Coronavirus/immunology , Vaccination , Young Adult
5.
Lancet Glob Health ; 9(7): e925-e931, 2021 07.
Article in English | MEDLINE | ID: covidwho-1303720

ABSTRACT

BACKGROUND: Detection of anti-SARS-CoV-2 antibodies among people at risk of infection is crucial for understanding both the past transmission of COVID-19 and vulnerability of the population to continuing transmission and, when done serially, the intensity of ongoing transmission over an interval in a community. We aimed to estimate the seroprevalence of COVID-19 in a representative population-based cohort in Iquitos, one of the regions with the highest mortality rates from COVID-19 in Peru, where a devastating number of cases occurred in March, 2020. METHODS: We did a population-based study of SARS-CoV-2 transmission in Iquitos at two timepoints: July 13-18, 2020 (baseline), and Aug 13-18, 2020 (1-month follow-up). We obtained a geographically stratified representative sample of the city population using the 2017 census data, which was updated on Jan 20, 2020. We included people who were inhabitants of Iquitos since COVID-19 was identified in Peru (March 6, 2020) or earlier. We excluded people living in institutions, people receiving any pharmacological treatment for COVID-19, people with any contraindication for phlebotomy, and health workers or individuals living with an active health worker. We tested each participant for IgG and IgM anti-SARS-CoV-2 antibodies using the COVID-19 IgG/IgM Rapid Test (Zhejiang Orient Gene Biotech, China). We used survey analysis methods to estimate seroprevalence accounting for the sampling design effect and test performance characteristics. FINDINGS: We identified 726 eligible individuals and enrolled a total of 716 participants (99%), distributed across 40 strata (four districts, two sexes, and five age groups). We excluded ten individuals who: did not have consent from a parent or legal representative (n=3), had moved to Iquitos after March 6, 2020 (n=3), were in transit (n=2), or had respiratory symptoms (n=1). After adjusting for the study sampling effects and sensitivity and specificity of the test, we estimated a seroprevalence of 70% (95% CI 67-73) at baseline and 66% (95% CI 62-70) at 1 month of follow-up, with a test-retest positivity of 65% (95% CI 61-68), and an incidence of new exposures of 2% (95% CI 1-3). We observed significant differences in the seroprevalence between age groups, with participants aged 18-29 years having lower seroprevalence than those aged younger than 12 years (prevalence ratio 0·85 [95% CI 0·73-0·98]; p=0·029). INTERPRETATION: After the first epidemic peak, Iquitos had one of the highest rates of seroprevalence of anti-SARS-CoV-2 antibodies worldwide. Nevertheless, the city experienced a second wave starting in January, 2021, probably due to the emergence of the SARS-CoV-2 P1 variant, which has shown higher transmissibility and reinfection rates. FUNDING: Dirección Regional de Salud de Loreto (DIRESA), Loreto, Peru. TRANSLATION: For the Spanish translation of the abstract see Supplementary Materials section.


Subject(s)
Antibodies, Viral/blood , COVID-19/epidemiology , COVID-19/virology , SARS-CoV-2/immunology , Adolescent , Adult , Child , Cohort Studies , Female , Humans , Male , Middle Aged , Peru/epidemiology , Seroepidemiologic Studies , Young Adult
6.
Immunology ; 164(1): 135-147, 2021 09.
Article in English | MEDLINE | ID: covidwho-1295026

ABSTRACT

Detecting antibody responses during and after SARS-CoV-2 infection is essential in determining the seroepidemiology of the virus and the potential role of antibody in disease. Scalable, sensitive and specific serological assays are essential to this process. The detection of antibody in hospitalized patients with severe disease has proven relatively straightforward; detecting responses in subjects with mild disease and asymptomatic infections has proven less reliable. We hypothesized that the suboptimal sensitivity of antibody assays and the compartmentalization of the antibody response may contribute to this effect. We systematically developed an ELISA, optimizing different antigens and amplification steps, in serum and saliva from non-hospitalized SARS-CoV-2-infected subjects. Using trimeric spike glycoprotein, rather than nucleocapsid, enabled detection of responses in individuals with low antibody responses. IgG1 and IgG3 predominate to both antigens, but more anti-spike IgG1 than IgG3 was detectable. All antigens were effective for detecting responses in hospitalized patients. Anti-spike IgG, IgA and IgM antibody responses were readily detectable in saliva from a minority of RT-PCR confirmed, non-hospitalized symptomatic individuals, and these were mostly subjects who had the highest levels of anti-spike serum antibodies. Therefore, detecting antibody responses in both saliva and serum can contribute to determining virus exposure and understanding immune responses after SARS-CoV-2 infection.


Subject(s)
Antibodies, Viral/immunology , COVID-19/immunology , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Antigens, Viral/immunology , COVID-19/blood , COVID-19/diagnosis , Enzyme-Linked Immunosorbent Assay , Humans , Saliva
7.
Int J Infect Dis ; 109: 17-23, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1267698

ABSTRACT

BACKGROUND: The distribution and nature of symptoms among SARS-CoV-2 infected individuals need to be clarified. METHODS: Between May and August 2020, 11 138 healthcare and administrative personnel from Central Denmark Region were tested for SARS-CoV-2 antibodies and subsequently completed a questionnaire. Symptom prevalence and overall duration for symptoms persisting for more than 30 days were calculated. Logistic regression models were used to estimate adjusted odds ratios (ORs) with 95% CIs. RESULTS: In total, 447 (4%) of the participants were SARS-CoV-2-seropositive. Loss of sense of smell and taste was reported by 50% of seropositives compared with 3% of seronegatives. Additionally, seropositives more frequently reported fever, dyspnoea, muscle or joint ache, fatigue, cough, headache and sore throat, and they were more likely to report symptoms persisting for more than 30 days. In adjusted models, they had a higher risk of reporting symptoms, with the strongest association observed for loss of sense of taste and smell (OR = 35.6; 95% CI: 28.6-44.3). CONCLUSION: In this large study, SARS-CoV-2-seropositive participants reported COVID-19-associated symptoms more frequently than those who were seronegative, especially loss of sense of taste and smell. Overall, their symptoms were also more likely to persist for more than 30 days.


Subject(s)
COVID-19 , SARS-CoV-2 , Administrative Personnel , Delivery of Health Care , Denmark/epidemiology , Humans
8.
J Med Life ; 14(2): 257-261, 2021.
Article in English | MEDLINE | ID: covidwho-1262738

ABSTRACT

The coronavirus disease 2019 (COVID-19) was declared a pandemic by the World Health Organization (WHO) on the 11th of March 2020. In Romania, there have been 983,217 confirmed cases and 24,386 deaths. We aim to show our experience at the Fundeni Clinical Institute in the diagnosis of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection in both patients and health care personnel. Swab samples were collected for extraction of the SARS-CoV-2 RNA from 29380 patients and health care personnel. We have combined three real-time reverse transcription-polymerase chain reaction (RT-PCR) assays for the qualitative detection of SARS-CoV-2. Also, the presence of IgG against SARS-CoV-2 nucleoprotein was analyzed in 1068 patients and clinical staff using the chemiluminescence method. Other 50 people were screened post-vaccination for the presence of SARS-CoV-2 antibodies against the spike (S) protein, using the chemiluminescence method as well. The majority of confirmed cases were in adults, 71.3% of cases being registered in people aged 30-69 years. Most patients diagnosed with SARS-CoV-2 infection (83%) were admitted to the gastroenterology, hematology, and surgery wards. Our study showed that one-third of people developed antibodies against the nucleocapsid of SARS-CoV-2. SARS-CoV-2 IgG seroprevalence does not vary by gender or age. Also, we noticed the presence of antibodies against the SARS-CoV-2 spike protein in all 50 people post-vaccination that were tested two weeks after the second dose. Due to the increasing number of infected patients with SARS-CoV-2, the new coronavirus pandemic involves a sustained testing effort for an accurate virological diagnosis in both direct and indirect diagnosis.


Subject(s)
COVID-19/diagnosis , COVID-19/virology , SARS-CoV-2/physiology , Adult , Aged , Antibodies, Viral/immunology , COVID-19/genetics , COVID-19/immunology , COVID-19 Serological Testing , Female , Health Personnel , Humans , Immunoglobulin G/immunology , Male , Middle Aged , Pandemics , RNA, Viral , Real-Time Polymerase Chain Reaction , Romania
9.
ERJ Open Res ; 7(2)2021 Apr.
Article in English | MEDLINE | ID: covidwho-1262495

ABSTRACT

BACKGROUND: Healthcare workers (HCWs) are believed to be at increased risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. It is not known to what extent the natural production of antibodies to SARS-CoV-2 is protective against re-infection. METHODS: A prospective observational study of HCWs in Scotland (UK) from May to September 2020 was performed. The Siemens SARS-CoV-2 total antibody assay was used to establish seroprevalence in this cohort. Controls, matched for age and sex to the general local population, were studied for comparison. New infections (up to 2 December 2020) post antibody testing were recorded to determine whether the presence of SARS-CoV-2 antibodies protects against re-infection. RESULTS: A total of 2063 health and social care workers were recruited for this study. At enrolment, 300 HCWs had a positive antibody test (14.5%). 11 out of 231 control sera tested positive (4.8%). HCWs therefore had an increased likelihood of a positive test (OR 3.4, 95% CI 1.85-6.16; p<0.0001). Dentists were most likely to test positive. 97.3% of patients who had previously tested positive for SARS-CoV-2 by reverse transcriptase (RT)-PCR had positive antibodies. 18.7% had an asymptomatic infection. There were 38 new infections with SARS-CoV-2 in HCWs who were previously antibody negative, and one symptomatic RT-PCR-positive re-infection. The presence of antibodies was therefore associated with an 85% reduced risk of re-infection with SARS-CoV-2 (hazard ratio 0.15, 95% CI 0.06-0.35; p=0.026). CONCLUSION: HCWs were three times more likely to test positive for SARS-CoV-2 than the general population. Almost all infected individuals developed an antibody response, which was 85% effective in protecting against re-infection with SARS-CoV-2.

10.
BMJ Open ; 11(6): e051415, 2021 06 08.
Article in English | MEDLINE | ID: covidwho-1262401

ABSTRACT

OBJECTIVE: This study investigated seroprevalence of SARS-CoV-2-specific IgG antibodies, using the Abbott antinucleocapsid IgG chemiluminescent microparticle immunoassay (CMIA) assay, in five prespecified healthcare worker (HCW) subgroups following the first wave of the COVID-19 pandemic. SETTING: An 800-bed tertiary-level teaching hospital in the south of Ireland. PARTICIPANTS: Serum was collected for anti-SARS-CoV-2 nucleocapsid IgG using the Abbott ARCHITECT SARS-CoV-2 IgG CMIA qualitative assay, as per the manufacturer's specifications.The groups were as follows: (1) HCWs who had real-time PCR (RT-PCR) confirmed COVID-19 infection (>1-month postpositive RT-PCR); (2) HCWs identified as close contacts of persons with COVID-19 infection and who subsequently developed symptoms (virus not detected by RT-PCR on oropharyngeal/nasopharyngeal swab); (3) HCWs identified as close contacts of COVID-19 cases and who remained asymptomatic (not screened by RT-PCR); (4) HCWs not included in the aforementioned groups working in areas determined as high-risk clinical areas; and (5) HCWs not included in the aforementioned groups working in areas determined as low-risk clinical areas. RESULTS: Six of 404 (1.49%) HCWs not previously diagnosed with SARS-CoV-2 infection (groups 2-5) were seropositive for SARS-CoV-2 at the time of recruitment into the study.Out of the 99 participants in group 1, 72 had detectable IgG to SARS-CoV-2 on laboratory testing (73%). Antibody positivity correlated with shorter length of time between RT-PCR positivity and antibody testing.Quantification cycle value on RT-PCR was not found to be correlated with antibody positivity. CONCLUSIONS: Seroprevalence of SARS-CoV-2 antibodies in HCWs who had not previously tested RT-PCR positive for COVID-19 was low compared with similar studies.


Subject(s)
COVID-19 , Pandemics , Antibodies, Viral , Health Personnel , Humans , Ireland/epidemiology , SARS-CoV-2 , Seroepidemiologic Studies
11.
Biosens Bioelectron ; 190: 113414, 2021 Oct 15.
Article in English | MEDLINE | ID: covidwho-1252505

ABSTRACT

Antibody detection methods for viral infections have received broad attention due to the COVID-19 pandemic. In addition, there remains an ever-increasing need to quantitatively evaluate the immune response to develop vaccines and treatments for COVID-19. Here, we report an analytical method for the rapid and quantitative detection of SARS-CoV-2 antibody in human serum by fluorescence polarization immunoassay (FPIA). A recombinant SARS-CoV-2 receptor binding domain (RBD) protein labeled with HiLyte Fluor 647 (F-RBD) was prepared and used for FPIA. When the anti-RBD antibody in human serum binds to F-RBD, the degree of polarization (P) increases by suppressing the rotational diffusion of F-RBD. The measurement procedure required only mixing a reagent containing F-RBD with serum sample and measuring the P value with a portable fluorescence polarization analyzer after 15 min incubation. We evaluated analytical performance of the developed FPIA system using 30 samples: 20 COVID-19 positive sera and 10 negative sera. The receiver operating characteristic curve drawn with the obtained results showed that this FPIA system had high accuracy for discriminating COVID-19 positive or negative serum (AUC = 0.965). The total measurement time was about 20 min, and the serum volume required for measurement was 0.25 µL. Therefore, we successfully developed the FPIA system that enables rapid and easy quantification of SARS-CoV-2 antibody. It is believed that our FPIA system will facilitate rapid on-site identification of infected persons and deepen understanding of the immune response to COVID-19.


Subject(s)
Biosensing Techniques , COVID-19 , Antibodies, Viral , Fluorescence Polarization Immunoassay , Humans , Pandemics , SARS-CoV-2
12.
Clin Exp Immunol ; 205(3): 363-378, 2021 09.
Article in English | MEDLINE | ID: covidwho-1249405

ABSTRACT

Since December 2019, Coronavirus disease-19 (COVID-19) has spread rapidly throughout the world, leading to a global effort to develop vaccines and treatments. Despite extensive progress, there remains a need for treatments to bolster the immune responses in infected immunocompromised individuals, such as cancer patients who recently underwent a haematopoietic stem cell transplantation. Immunological protection against COVID-19 is mediated by both short-lived neutralizing antibodies and long-lasting virus-reactive T cells. Therefore, we propose that T cell therapy may augment efficacy of current treatments. For the greatest efficacy with minimal adverse effects, it is important that any cellular therapy is designed to be as specific and directed as possible. Here, we identify T cells from COVID-19 patients with a potentially protective response to two major antigens of the SARS-CoV-2 virus, Spike and Nucleocapsid protein. By generating clones of highly virus-reactive CD4+ T cells, we were able to confirm a set of nine immunodominant epitopes and characterize T cell responses against these. Accordingly, the sensitivity of T cell clones for their specific epitope, as well as the extent and focus of their cytokine response was examined. Moreover, using an advanced T cell receptor (TCR) sequencing approach, we determined the paired TCR-αß sequences of clones of interest. While these data on a limited population require further expansion for universal application, the results presented here form a crucial first step towards TCR-transgenic CD4+ T cell therapy of COVID-19.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/virology , COVID-19/immunology , COVID-19/therapy , Coronavirus Nucleocapsid Proteins/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Adult , Aged , Aged, 80 and over , Amino Acid Sequence , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/virology , COVID-19/virology , Clone Cells/immunology , Clone Cells/virology , Coronavirus Nucleocapsid Proteins/chemistry , Coronavirus Nucleocapsid Proteins/genetics , Cytokines/biosynthesis , Epitopes, T-Lymphocyte/chemistry , Epitopes, T-Lymphocyte/genetics , Epitopes, T-Lymphocyte/immunology , Female , Humans , Immunization, Passive , Immunodominant Epitopes/chemistry , Immunodominant Epitopes/genetics , Immunodominant Epitopes/immunology , Male , Middle Aged , Phosphoproteins/chemistry , Phosphoproteins/genetics , Phosphoproteins/immunology , Receptors, Antigen, T-Cell, alpha-beta/genetics , Receptors, Antigen, T-Cell, alpha-beta/immunology , SARS-CoV-2/chemistry , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics
13.
Clin Ther ; 43(6): e157-e162, 2021 06.
Article in English | MEDLINE | ID: covidwho-1245896

ABSTRACT

The use of monoclonal antibodies in children with certain conditions and at high risk for severe COVID-19 has been approved by the US Food and Drug Administration under the Emergency Use Authorization mechanism of the Federal Food, Drug, and Cosmetic Act. No data on the tolerability or efficacy of these therapies in persons <18 years of age are available; there is risk. Whether they will work is unknown, but they could. A disproportionate number of these children who meet the criteria for treatment with mAbs are from communities of black, Native American, and other race. How should health systems, hospitals, and clinicians balance the tensions between being seen as experimenting with an untested drug as opposed to withholding a potentially life-saving treatment? This article identifies, analyzes, and makes recommendations on the methods by which health systems, hospitals, and individual clinicians can ethically balance these tensions.


Subject(s)
Antineoplastic Agents, Immunological , COVID-19 , Antibodies, Monoclonal , Child , Humans , SARS-CoV-2 , United States , United States Food and Drug Administration
14.
Immun Inflamm Dis ; 9(3): 905-917, 2021 09.
Article in English | MEDLINE | ID: covidwho-1224967

ABSTRACT

BACKGROUND: Hamburg is a city state of approximately 1.9 Mio inhabitants in Northern Germany. Currently, the COVID-19 epidemic that had largely subsided during last summer is resurging in Hamburg and in other parts of the world, underlining the need for additional tools to monitor SARS-CoV-2 antibody responses. AIM: We aimed to develop and validate a simple, low-cost assay for detecting antibodies against the native coronavirus 2 spike protein (CoV-2 S) that does not require recombinant protein or virus. METHOD: We transiently co-transfected HEK cells or CHO cells with expression vectors encoding CoV-2 S and nuclear GFP. Spike protein-specific antibodies in human serum samples bound to transfected cells were detected with fluorochrome conjugated secondary antibodies by flow cytometry orimmunofluorescence microscopy. We applied this assay to monitor antibody development in COVID-19 patients, household contacts, and hospital personnel during the ongoing epidemic in the city state of Hamburg. RESULTS: All recovered COVID-19 patients showed high levels of CoV-2 S-specific antibodies. With one exception, all household members that did not develop symptoms also did not develop detectable antibodies. Similarly, lab personnel that worked during the epidemic and followed social distancing guidelines remained antibody-negative. CONCLUSION: We conclude that high-titer CoV-2 S-specific antibodies are found in most recovered COVID-19 patients and in symptomatic contacts, but only rarely in asymptomatic contacts. The assay may help health care providers to monitor disease progression and antibody responses in vaccination trials, to identify health care personnel that likely are resistant to re-infection, and recovered individuals with high antibody titers that may be suitable asplasma and/or antibody donors.


Subject(s)
Antibodies, Viral/analysis , COVID-19 , Spike Glycoprotein, Coronavirus , Adult , Aged , Aged, 80 and over , Animals , COVID-19/immunology , Cricetinae , Cricetulus , Flow Cytometry , HEK293 Cells , Humans , Middle Aged , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology
15.
Acta Naturae ; 13(1): 102-115, 2021.
Article in English | MEDLINE | ID: covidwho-1218997

ABSTRACT

The coronavirus disease outbreak in 2019 (COVID-19) has now achieved the level of a global pandemic and affected more than 100 million people on all five continents and caused over 2 million deaths. Russia is, needless to say, among the countries affected by SARS-CoV-2, and its health authorities have mobilized significant efforts and resources to fight the disease. The paper presents the result of a functional analysis of 155 patients in the Moscow Region who were examined at the Central Clinical Hospital of the Russian Academy of Sciences during the first wave of the pandemic (February-July, 2020). The inclusion criteria were a positive PCR test and typical, computed tomographic findings of viral pneumonia in the form of ground-glass opacities. A clinical correlation analysis was performed in four groups of patients: (1) those who were not on mechanical ventilation, (2) those who were on mechanical ventilation, and (3) those who subsequently recovered or (4) died. The correlation analysis also considered confounding comorbidities (diabetes, metabolic syndrome, hypertension, etc.). The immunological status of the patients was examined (levels of immunoglobulins of the M, A, G classes and their subclasses, as well as the total immunoglobulin level) using an original SARS-CoV-2 antibody ELISA kit. The ELISA kit was developed using linear S-protein RBD-SD1 and NTD fragments, as well as the N-protein, as antigens. These antigens were produced in the prokaryotic E. coli system. Recombinant RBD produced in the eukaryotic CHO system (RBD CHO) was used as an antigen representing conformational RBD epitopes. The immunoglobulin A level was found to be the earliest serological criterion for the development of a SARS-CoV-2 infection and it yielded the best sensitivity and diagnostic significance of ELISA compared to that of class M immunoglobulin. We demonstrated that the seroconversion rate of "early" N-protein-specific IgM and IgA antibodies is comparable to that of antibodies specific to RBD conformational epitopes. At the same time, seroconversion of SARS-CoV-2 N-protein-specific class G immunoglobulins was significantly faster compared to that of other specific antibodies. Our findings suggest that the strong immunogenicity of the RBD fragment is for the most part associated with its conformational epitopes, while the linear RBD and NTD epitopes have the least immunogenicity. An analysis of the occurrence rate of SARS-CoV-2-specific immunoglobulins of different classes revealed that RBD- and N-specific antibodies should be evaluated in parallel to improve the sensitivity of ELISA. An analysis of the immunoglobulin subclass distribution in sera of seropositive patients revealed uniform induction of N-protein-specific IgG subclasses G1-G4 and IgA subclasses A1-A2 in groups of patients with varying severity of COVID-19. In the case of the S-protein, G1, G3, and A1 were the main subclasses of antibodies involved in the immune response.

16.
J Clin Invest ; 131(12)2021 06 15.
Article in English | MEDLINE | ID: covidwho-1218257

ABSTRACT

BACKGROUNDThe COVID-19 vaccines currently in use require 2 doses to achieve optimal protection. Currently, there is no indication as to whether individuals who have been exposed to SARS-CoV-2 should be vaccinated, or whether they should receive 1 or 2 vaccine doses.METHODSWe tested the antibody response developed after administration of the Pfizer/BioNTech vaccine in 124 health care professionals, of whom 57 had a previous history of SARS-CoV-2 exposure with or without symptoms.RESULTSPostvaccine antibodies in SARS-CoV-2-exposed individuals increased exponentially within 5 to 18 days after the first dose compared to naive subjects (P < 0.0001). In a multivariate linear regression (LR) model we showed that the antibody response depended on the IgG prevaccine titer and on the exposure to SARS-CoV-2. In symptomatic SARS-CoV-2-exposed individuals, IgG reached a plateau after the second dose, and those who voluntarily refrained from receiving the second dose (n = 7) retained their antibody response. Gastrointestinal symptoms, muscle pain, and fever markedly positively correlated with increased IgG responses. By contrast, all asymptomatic/paucisymptomatic and unexposed individuals showed an important increase after the second dose.CONCLUSIONOne vaccine dose is sufficient in symptomatic SARS-CoV-2-exposed subjects to reach a high titer of antibodies, suggesting no need for a second dose, particularly in light of current vaccine shortage.TRIAL REGISTRATIONClinicalTrials.gov NCT04387929.FUNDINGDolce & Gabbana and the Italian Ministry of Health (Ricerca corrente).


Subject(s)
Antibodies, Viral , Antibody Formation/drug effects , COVID-19 Vaccines/administration & dosage , COVID-19 , SARS-CoV-2 , Adult , Antibodies, Viral/blood , Antibodies, Viral/immunology , COVID-19/blood , COVID-19/immunology , COVID-19 Vaccines/immunology , Female , Humans , Male , Middle Aged , SARS-CoV-2/immunology , SARS-CoV-2/metabolism
17.
J Clin Endocrinol Metab ; 106(5): e2025-e2034, 2021 04 23.
Article in English | MEDLINE | ID: covidwho-1199961

ABSTRACT

PURPOSE: Comorbidities making up metabolic syndrome (MetS), such as obesity, type 2 diabetes, and chronic cardiovascular disease can lead to increased risk of coronavirus disease-2019 (COVID-19) with a higher morbidity and mortality. SARS-CoV-2 antibodies are higher in severely or critically ill COVID-19 patients, but studies have not focused on levels in convalescent patients with MetS, which this study aimed to assess. METHODS: This retrospective study focused on adult convalescent outpatients with SARS-CoV-2 positive serology during the COVID-19 pandemic at NewYork Presbyterian/Weill Cornell. Data collected for descriptive and correlative analysis included SARS-COV-2 immunoglobin G (IgG) levels and history of MetS comorbidities from April 17, 2020 to May 20, 2020. Additional data, including SARS-CoV-2 IgG levels, body mass index (BMI), hemoglobin A1c (HbA1c) and lipid levels were collected and analyzed for a second cohort from May 21, 2020 to June 21, 2020. SARS-CoV-2 neutralizing antibodies were measured in a subset of the study cohort. RESULTS: SARS-CoV-2 IgG levels were significantly higher in convalescent individuals with MetS comorbidities. When adjusted for age, sex, race, and time duration from symptom onset to testing, increased SARS-CoV-2 IgG levels remained significantly associated with obesity (P < 0.0001). SARS-CoV-2 IgG levels were significantly higher in patients with HbA1c ≥6.5% compared to those with HbA1c <5.7% (P = 0.0197) and remained significant on multivariable analysis (P = 0.0104). A positive correlation was noted between BMI and antibody levels [95% confidence interval: 0.37 (0.20-0.52) P < 0.0001]. Neutralizing antibody titers were higher in COVID-19 individuals with BMI ≥ 30 (P = 0.0055). CONCLUSION: Postconvalescent SARS-CoV-2 IgG and neutralizing antibodies are elevated in obese patients, and a positive correlation exists between BMI and antibody levels.


Subject(s)
Antibodies, Neutralizing/immunology , COVID-19/immunology , Immunoglobulin G/immunology , Metabolic Syndrome/immunology , Adult , Antibodies, Neutralizing/blood , COVID-19/blood , COVID-19/complications , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/immunology , Diabetes Mellitus, Type 2/virology , Female , Humans , Immunoglobulin G/blood , Male , Metabolic Syndrome/blood , Metabolic Syndrome/virology , Middle Aged , Obesity/blood , Obesity/immunology , Obesity/virology , Retrospective Studies
18.
JAMA Intern Med ; 181(7): 960-966, 2021 07 01.
Article in English | MEDLINE | ID: covidwho-1196360

ABSTRACT

Importance: Clinical data are lacking regarding the risk of viral transmission from individuals who have positive reverse-transcription-polymerase chain reaction (RT-PCR) SARS-CoV-2 test results after recovery from COVID-19. Objective: To describe case characteristics, including viral dynamics and transmission of infection, for individuals who have clinically recovered from SARS-CoV-2 infection but continued to have positive test results following discontinuation of isolation precautions. Design, Setting, and Participants: This retrospective cohort study used data collected from June 11, 2020, to October 19, 2020, as part of the National Basketball Association (NBA) closed campus occupational health program in Orlando, Florida, which required daily RT-PCR testing and ad hoc serological testing for SARS-CoV-2 IgG antibodies. Nearly 4000 NBA players, staff, and vendors participated in the NBA's regular and postseason occupational health program in Orlando. Persistent positive cases were those who recovered from a documented SARS-CoV-2 infection, satisfied US Centers for Disease Control and Prevention criteria for discontinuation of isolation precautions, and had at least 1 postinfection positive RT-PCR test(s) result. Exposures: Person-days of participation in indoor, unmasked activities that involved direct exposure between persistent positive cases and noninfected individuals. Main Outcomes and Measures: Transmission of SARS-CoV-2 following interaction with persistent positive individuals, as measured by the number of new COVID-19 cases in the Orlando campus program. Results: Among 3648 individuals who participated, 36 (1%) were persistent positive cases, most of whom were younger than 30 years (24 [67%]) and male (34 [94%]). Antibodies were detected in 33 individuals (91.7%); all remained asymptomatic following the index persistent positive RT-PCR result. Cycle threshold values for persistent positive RT-PCR test results were typically above the Roche cobas SARS-CoV-2 limit of detection. Cases were monitored for up to 100 days (mean [SD], 51 [23.9] days), during which there were at least 1480 person-days of direct exposure activities, with no transmission events or secondary infections of SARS-CoV-2 detected (0 new cases). Conclusions and Relevance: In this retrospective cohort study of the 2020 NBA closed campus occupational health program, recovered individuals who continued to test positive for SARS-CoV-2 following discontinuation of isolation were not infectious to others. These findings support time-based US Centers of Disease Control and Prevention recommendations for ending isolation.


Subject(s)
Antibodies, Viral/analysis , Basketball/statistics & numerical data , COVID-19/transmission , Disease Transmission, Infectious/statistics & numerical data , Pandemics , SARS-CoV-2/immunology , Adolescent , Adult , COVID-19/epidemiology , Female , Follow-Up Studies , Humans , Male , Retrospective Studies , United States/epidemiology , Young Adult
19.
Commun Biol ; 4(1): 486, 2021 04 20.
Article in English | MEDLINE | ID: covidwho-1195630

ABSTRACT

There is an ongoing need of developing sensitive and specific methods for the determination of SARS-CoV-2 seroconversion. For this purpose, we have developed a multiplexed flow cytometric bead array (C19BA) that allows the identification of IgG and IgM antibodies against three immunogenic proteins simultaneously: the spike receptor-binding domain (RBD), the spike protein subunit 1 (S1) and the nucleoprotein (N). Using different cohorts of samples collected before and after the pandemic, we show that this assay is more sensitive than ELISAs performed in our laboratory. The combination of three viral antigens allows for the interrogation of full seroconversion. Importantly, we have detected N-reactive antibodies in COVID-19-negative individuals. Here we present an immunoassay that can be easily implemented and has superior potential to detect low antibody titers compared to current gold standard serology methods.


Subject(s)
Antibodies, Viral/immunology , COVID-19/diagnosis , Flow Cytometry/methods , Nucleoproteins/immunology , SARS-CoV-2/immunology , Seroconversion , Antigens, Viral/immunology , COVID-19/epidemiology , COVID-19/virology , Humans , Immunoassay/methods , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Pandemics , Reproducibility of Results , SARS-CoV-2/physiology , Sensitivity and Specificity
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