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1.
J Formos Med Assoc ; 121(12): 2438-2445, 2022 Dec.
Статья в английский | MEDLINE | ID: covidwho-2210778

Реферат

BACKGROUND: Whether immunocompromising conditions affect the immunogenicity of COVID-19 booster vaccination remains a concern, which impedes the vaccination campaign in people most vulnerable to COVID-19-associated morbidity and mortality. We aimed to evaluate the effect of immune dysfunction on immunogenicity of homologous and heterologous prime-boost COVID-19 vaccination. METHODS: Between July and August, 2021, 399 participants were randomized to receive ChAdOx1/ChAdOx1 8 weeks apart, ChAdOx1/mRNA-1273 8 weeks apart, ChAdOx1/mRNA-1273 4 weeks apart, and mRNA-1273/mRNA-1273 4 weeks apart. The anti-SARS-CoV-2 spike IgG antibody titers on the day before booster vaccination and 4 weeks after booster vaccination were compared between participants with and without immunocompromising conditions. RESULTS: Among ChAdOx1-primed participants, a trend of lower anti-SARS-CoV-2 spike IgG titers before booster vaccination were found in participants with autoimmune diseases (geometric means, 34.76 vs. 84.25 binding antibody units [BAU]/mL, P = 0.173), compared to those without. Participants receiving immunosuppressants and/or immunomodulators had significant lower anti-SARS-CoV-2 spike IgG titers before booster vaccination than those without (geometric means, 36.39 vs. 83.84 BAU/mL; P = 0.001). Among mRNA-1273-boosted participants, anti-SARS-CoV-2 spike IgG titers 4 weeks after booster vaccination were similar across all the strata. Participants with autoimmune diseases and receiving immunosuppressants and/or immunomodulators, had numerically lower anti-SARS-CoV-2 spike IgG titers 4 weeks after booster vaccination compared to those without (geometric means, 1474.34 vs. 1923.23 and 1590.61 vs. 1918.38 BAU/mL; P > 0.05). CONCLUSION: The immunogenicity of prime vaccination with ChAdOx1 decreased by immune dysfunction, but enhanced after receiving boost vaccination with mRNA-1273. Our study results support the efficacy of mRNA-1273 booster dose among immunocompromised hosts.


Тема - темы
Autoimmune Diseases , COVID-19 , Humans , Immunization, Secondary/methods , 2019-nCoV Vaccine mRNA-1273 , COVID-19/prevention & control , Taiwan , Antibodies, Viral , Immunocompromised Host , Vaccination , Immunoglobulin G , Adjuvants, Immunologic , Immunosuppressive Agents
2.
Indian J Med Res ; 155(1): 171-177, 2022 01.
Статья в английский | MEDLINE | ID: covidwho-2201777

Реферат

Background & objectives: Serology testing is essential for immunological surveillance in the population. This serosurvey was conducted to ascertain the cumulative population immunity against SARS-CoV-2 among adults in Jammu district and to understand the association of seropositivity with sociodemographic and clinical correlates. Methods: On September 30 and October 1, 2020, a household survey was done in 20 villages/wards chosen from 10 health blocks in district Jammu, India. Demographic, clinical and exposure information was collected from 2000 adults. Serum samples were screened for IgG antibodies using COVID Kavach MERILISA kit. Tests of association were used to identify risk factors associated with IgG positivity. Crude odds ratio with 95 per cent confidence intervals (CIs) was calculated during univariate analysis followed by logistic regression. Results: Overall adjusted seroprevalence for SARS-CoV-2 was 8.8 per cent (95% CI: 8.78-8.82); it varied from 4.1 per cent in Chauki choura to 16.7 per cent Pallanwalla across 10 blocks in the district. Seropositivity was observed to be comparatively higher in 41-50 and 61-70 yr age groups, among males and in rural areas. Fever, sore throat, cough, dyspnoea, myalgias, anosmia, ageusia, fatigue, seizures, history of exposure, medical consultation, hospitalization and missing work showed significant association with seropositivity on univariate analysis. On logistic regression, only sore throat, myalgia and missing work showed significant adjusted odds of IgG positivity. Extrapolation to adult population suggested that exposure to SARS-CoV-2 was 14.4 times higher than reported cases, translating into Infection fatality rate of 0.08 per cent. Interpretation & conclusions: Since a major part of population was immunologically naive, all efforts to contain COVID-19 need to be vigorously followed while these baseline results provide an important yardstick to monitor the trends of COVID-19 and guide locally appropriate control strategies in the region.


Тема - темы
COVID-19 , Pharyngitis , Adult , Antibodies, Viral , COVID-19/epidemiology , Humans , Immunoglobulin G , Male , SARS-CoV-2 , Seroepidemiologic Studies
3.
Front Immunol ; 13: 918896, 2022.
Статья в английский | MEDLINE | ID: covidwho-2198845

Реферат

Background: Effective and safe vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are critical to controlling the COVID-19 pandemic and will remain the most important tool in limiting the spread of the virus long after the pandemic is over. Methods: We bring pioneering contributions on the maintenance of the immune response over a year on a real-life basis study in 1,587 individuals (18-90 yrs, median 39 yrs; 1,208 female/379 male) who underwent vaccination with two doses of CoronaVac and BNT162b2 booster after 6-months of primary protocol. Findings: Elevated levels of anti-spike IgG antibodies were detected after CoronaVac vaccination, which significantly decreased after 80 days and remained stable until the introduction of the booster dose. Heterologous booster restored antibody titers up to-1·7-fold, changing overall seropositivity to 96%. Titers of neutralising antibodies to the Omicron variant were lower in all timepoints than those against Delta variant. Individuals presenting neutralising antibodies against Omicron also presented the highest titers against Delta and anti-Spike IgG. Cellular immune response measurement pointed out a mixed immune profile with a robust release of chemokines, cytokines, and growth factors on the first month after CoronaVac vaccination followed by a gradual reduction over time and no increase after the booster dose. A stronger interaction between those mediators was noted over time. Prior exposure to the virus leaded to a more robust cellular immune response and a rise in antibody levels 60 days post CoronaVac than in individuals with no previous COVID-19. Both vaccines were safe and well tolerated among individuals. Interpretation: Our data approach the effectiveness of CoronaVac association with BNT162b2 from the clinical and biological perspectives, aspects that have important implications for informing decisions about vaccine boosters. Funding: Fiocruz, Brazil.


Тема - темы
COVID-19 Vaccines , COVID-19 , Immunization, Secondary , Immunogenicity, Vaccine , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine/immunology , Brazil , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , Female , Follow-Up Studies , Humans , Immunoglobulin G , Male , Pandemics , SARS-CoV-2
4.
Front Immunol ; 13: 915034, 2022.
Статья в английский | MEDLINE | ID: covidwho-2198841

Реферат

The rapid development, approval, and production of vaccines against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in less than 1 year after the first reports of a new infectious disease was a real game changer, providing 80%-90% efficacy in preventing severe etiopathologies of the coronavirus disease 2019 (COVID-19). These vaccines induce an immune response against the SARS-CoV-2 spike (S) protein located on the surface of the virus particle. Antibodies (Abs) recognizing the S-protein can inhibit binding of the virus via the S-protein to the angiotensin-converting enzyme-2 (ACE-2) receptor expressed on different human cells, especially when these Abs bind to the interaction site, the so-called receptor-binding domain (RBD). We have expressed the RBDs of wild-type SARS-CoV-2 and five variants of concern (VOCs) to test the immune response in people before vaccination with mRNA vaccines BNT162b2 and mRNA-1273 and after up to three vaccinations using in-house ELISA and inhibition assays. The methods of both assays are provided. Both vaccines initiated similarly high IgG titers after two vaccinations against the wild-type and even two VOC-RBDs (alpha and delta) and strongly inhibited the corresponding RBD-ACE-2 binding. The IgG titers and inhibition of ACE-2 binding were lower for beta and gamma RBDs and much lower for omicron RBD. The third vaccination after 6 months strongly increased both the IgG titers and the neutralizing effect against all variants, especially for omicron, leading to 63% ± 13% neutralization potential. Importantly, neutralization linearly increased with the IgG titers.


Тема - темы
COVID-19 , SARS-CoV-2 , BNT162 Vaccine , COVID-19/prevention & control , Humans , Immunoglobulin G , RNA, Messenger
5.
Front Immunol ; 13: 911738, 2022.
Статья в английский | MEDLINE | ID: covidwho-2198836

Реферат

Introduction: Vaccination is an effective strategy for preventing SARS-CoV-2 infection and associated mortality. Renal Transplant Recipients (RTRs) are vulnerable to acquiring infection and high mortality due to their immunocompromised state. Varying responses to the different vaccines, depending on types of vaccines and population, have been reported. Vaccines supply is also limited. The current study evaluated the seroconversion rate after SARS-CoV-2 infection and 2 doses of either COVAXIN™ or COVISHIELD™ vaccination in RTR. Methods: The serum anti-SARS-CoV-2 spike protein neutralizing antibody titer was measured in 370 RTRs who acquired SARS-CoV-2 infection (n=172), yet not vaccinated; and those vaccinated with COVAXIN™ (n=78), and COVISHIELD™ (n=120) by chemiluminescence microparticle immunoassay methods from serum. Result: Overall, the seroconversion rate either after vaccination or infection was 85.13% (315/370). The vaccine-associated seroconversion was 80.30% (159/198). SARS-CoV-2 infection-associated seroconversion was 90.69% (156/172), COVISHIELD™ associated seroconversion was 79.2% (95/120), and COVAXIN™ associated seroconversion was 82.05% (64/78). The median IgG titer in the SARS-CoV-2 infection group was 646.50 AU/ml (IQR: 232.52-1717.42), in the COVAXIN™ group was 1449.75 AU/ml (IQR: 400.0-3068.55), and the COVISHIELD™ vaccination group was 1500.51 AU/ml (IQR: 379.47-4938.50). The seroconversion rate and antibody titers were similar irrespective of the place of sampling. Patient's age-associated seroconversion in <45 years was 88.01% (213/242), 45.1-60 years was 83.18% (94/113), and > 60 years was 58.3% (7/12). Conclusions: Both infection and vaccination induce robust antibody formation in RTRs. The seroconversion rate after SARS-CoV-2 infection was higher but with a lower antibody titer than vaccines. The vaccines, COVAXIN™ and COVISHIELD™, induce more elevated antibody titers than natural infection. The seroconversion rate and antibody titer in Indian RTRs appears to be better than in the western population, irrespective of their vaccination status.


Тема - темы
COVID-19 , Kidney Transplantation , Allografts , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Immunoglobulin G , Middle Aged , SARS-CoV-2 , Seroconversion , Tertiary Care Centers , Vaccination , Vaccines, Inactivated
6.
Front Cell Infect Microbiol ; 12: 978440, 2022.
Статья в английский | MEDLINE | ID: covidwho-2198706

Реферат

Purpose: This study was conducted in order to properly understand whether prior seasonal human coronavirus (HCoV) immunity could impact the potential cross-reactivity of humoral responses induced by SARS-CoV-2 vaccine, thereby devising universal coronavirus vaccines for future outbreaks. Methods: We performed enzyme-linked immunosorbent assay (ELISA) to quantify the immunoglobulin G (IgG) antibody levels to spike (S) protein and S1 subunit of HCoVs (HCoV-OC43, HCoV-HKU1, HCoV-NL63, and HCoV-229E), and ELISA [anti-RBD and anti-nucleoprotein (N)], chemiluminescence immunoassay assays (anti-RBD), pseudovirus neutralization test, and authentic viral neutralization test to detect the binding and neutralizing antibodies to SARS-CoV-2 in the vaccinees. Results: We found that the antibody of seasonal HCoVs did exist before vaccination and could be boosted by SARS-CoV-2 vaccine. A further analysis demonstrated that the prior S and S1 IgG antibodies of HCoV-OC43 were positively correlated with anti-RBD and neutralization antibodies to SARS-CoV-2 at 12 and 24 weeks after the second vaccination, and the correlation is more statistically significant at 24 weeks. The persistent antibody levels of SARS-CoV-2 were observed in vaccinees with higher pre-existing HCoV-OC43 antibodies. Conclusion: Our data indicate that inactivated SARS-CoV-2 vaccination may confer cross-protection against seasonal coronaviruses in most individuals, and more importantly, the pre-existing HCoV-OC43 antibody was associated with protective immunity to SARS-CoV-2, supporting the development of a pan-coronavirus vaccine.


Тема - темы
COVID-19 , Coronavirus OC43, Human , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Immunoglobulin G , SARS-CoV-2 , Vaccination
7.
Front Cell Infect Microbiol ; 12: 932563, 2022.
Статья в английский | MEDLINE | ID: covidwho-2198700

Реферат

In Brazil, the coronavirus disease 2019 (COVID-19) epidemic spread rapidly in a heterogeneous way, mainly due to the different socioeconomic and behavioral characteristics of different regional populations and different evaluation periods. We performed a cross-sectional study including 1,337 individuals (first wave = 736/second wave = 601) after the first two waves of COVID-19 in the city of Belém, the capital of the state of Pará. The detection of IgG anti-SARS-CoV-2 antibodies was performed using an enzyme-linked immunosorbent assay test followed by statistical analysis using the RStudio program. Our results showed an increase in the seroprevalence (first wave= 39.1%/second wave= 50.1%) of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG antibodies in the population of Belém from the first to the second pandemic wave. Advanced age, primary or secondary education level, lack of social isolation, and a low frequency of protective mask use were considered risk factors for SARS-CoV-2 infection during the first wave compared to the second wave. This study is one of the firsts to provide important information about the dynamics of virus circulation and the groups vulnerable to exposure in the two major periods. Our data emphasize the socioeconomic characteristics of the affected population and that nonpharmacological prevention measures are crucial for combating the pandemic.


Тема - темы
COVID-19 , Antibodies, Viral , Brazil/epidemiology , COVID-19/epidemiology , Cross-Sectional Studies , Humans , Immunoglobulin G , Risk Factors , SARS-CoV-2 , Seroepidemiologic Studies
8.
PLoS Med ; 19(10): e1003979, 2022 10.
Статья в английский | MEDLINE | ID: covidwho-2196855

Реферат

BACKGROUND: Vaccines can be less immunogenic in people living with HIV (PLWH), but for SARS-CoV-2 vaccinations this is unknown. In this study we set out to investigate, for the vaccines currently approved in the Netherlands, the immunogenicity and reactogenicity of SARS-CoV-2 vaccinations in PLWH. METHODS AND FINDINGS: We conducted a prospective cohort study to examine the immunogenicity of BNT162b2, mRNA-1273, ChAdOx1-S, and Ad26.COV2.S vaccines in adult PLWH without prior COVID-19, and compared to HIV-negative controls. The primary endpoint was the anti-spike SARS-CoV-2 IgG response after mRNA vaccination. Secondary endpoints included the serological response after vector vaccination, anti-SARS-CoV-2 T-cell response, and reactogenicity. Between 14 February and 7 September 2021, 1,154 PLWH (median age 53 [IQR 44-60] years, 85.5% male) and 440 controls (median age 43 [IQR 33-53] years, 28.6% male) were included in the final analysis. Of the PLWH, 884 received BNT162b2, 100 received mRNA-1273, 150 received ChAdOx1-S, and 20 received Ad26.COV2.S. In the group of PLWH, 99% were on antiretroviral therapy, 97.7% were virally suppressed, and the median CD4+ T-cell count was 710 cells/µL (IQR 520-913). Of the controls, 247 received mRNA-1273, 94 received BNT162b2, 26 received ChAdOx1-S, and 73 received Ad26.COV2.S. After mRNA vaccination, geometric mean antibody concentration was 1,418 BAU/mL in PLWH (95% CI 1322-1523), and after adjustment for age, sex, and vaccine type, HIV status remained associated with a decreased response (0.607, 95% CI 0.508-0.725, p < 0.001). All controls receiving an mRNA vaccine had an adequate response, defined as >300 BAU/mL, whilst in PLWH this response rate was 93.6%. In PLWH vaccinated with mRNA-based vaccines, higher antibody responses were predicted by CD4+ T-cell count 250-500 cells/µL (2.845, 95% CI 1.876-4.314, p < 0.001) or >500 cells/µL (2.936, 95% CI 1.961-4.394, p < 0.001), whilst a viral load > 50 copies/mL was associated with a reduced response (0.454, 95% CI 0.286-0.720, p = 0.001). Increased IFN-γ, CD4+ T-cell, and CD8+ T-cell responses were observed after stimulation with SARS-CoV-2 spike peptides in ELISpot and activation-induced marker assays, comparable to controls. Reactogenicity was generally mild, without vaccine-related serious adverse events. Due to the control of vaccine provision by the Dutch National Institute for Public Health and the Environment, there were some differences between vaccine groups in the age, sex, and CD4+ T-cell counts of recipients. CONCLUSIONS: After vaccination with BNT162b2 or mRNA-1273, anti-spike SARS-CoV-2 antibody levels were reduced in PLWH compared to HIV-negative controls. To reach and maintain the same serological responses as HIV-negative controls, additional vaccinations are probably required. TRIAL REGISTRATION: The trial was registered in the Netherlands Trial Register (NL9214). https://www.trialregister.nl/trial/9214.


Тема - темы
COVID-19 Vaccines , COVID-19 , HIV Infections , Adult , Female , Humans , Male , Middle Aged , Ad26COVS1 , Antibodies, Viral , BNT162 Vaccine , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines/immunology , HIV Infections/immunology , Immunogenicity, Vaccine , Immunoglobulin G , Netherlands/epidemiology , Prospective Studies , RNA, Messenger , SARS-CoV-2
9.
Clin Infect Dis ; 75(1): e314-e321, 2022 08 24.
Статья в английский | MEDLINE | ID: covidwho-2188494

Реферат

BACKGROUND: An immunodiagnostic assay that sensitively detects a cell-mediated immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is needed for epidemiological investigation and for clinical assessment of T- cell-mediated immune response to vaccines, particularly in the context of emerging variants that might escape antibody responses. METHODS: The performance of a whole blood interferon-gamma (IFN-γ) release assay (IGRA) for the detection of SARS-CoV-2 antigen-specific T cells was evaluated in coronavirus disease 2019 (COVID-19) convalescents tested serially up to 10 months post-infection and in healthy blood donors. SARS-CoV-2 IGRA was applied in contacts of households with index cases. Freshly collected blood in the lithium heparin tube was left unstimulated, stimulated with a SARS-CoV-2 peptide pool, and stimulated with mitogen. RESULTS: The overall sensitivity and specificity of IGRA were 84.5% (153/181; 95% confidence interval [CI]: 79.0-89.0) and 86.6% (123/142; 95% CI: 80.0-91.2), respectively. The sensitivity declined from 100% (16/16; 95% CI: 80.6-100) at 0.5-month post-infection to 79.5% (31/39; 95% CI: 64.4-89.2) at 10 months post-infection (P < .01). The IFN-γ response remained relatively robust at 10 months post-infection (3.8 vs 1.3 IU/mL, respectively). In 14 households, IGRA showed a positivity rate of 100% (12/12) and 65.2% (15/23), and IgG of 50.0% (6/12) and 43.5% (10/23) in index cases and contacts, respectively, exhibiting a difference of + 50% (95% CI: +25.4 to +74.6) and +21.7% (95% CI: +9.23 to +42.3), respectively. Either IGRA or IgG was positive in 100% (12/12) of index cases and 73.9% (17/23) of contacts. CONCLUSIONS: The SARS-CoV-2 IGRA is a useful clinical diagnostic tool for assessing cell-mediated immune response to SARS-CoV-2.


Тема - темы
COVID-19 , SARS-CoV-2 , Antibodies, Viral , COVID-19/diagnosis , Humans , Immunoglobulin G , Interferon-gamma Release Tests , Sensitivity and Specificity
10.
Biopreserv Biobank ; 20(5): 423-428, 2022 Oct.
Статья в английский | MEDLINE | ID: covidwho-2188054

Реферат

Background: Antibodies with the specialized ability to fight infection can be found in the blood of individuals who have recovered from or have been vaccinated against COVID-19. As a result, plasma from these individuals could be used to treat critically ill patients. This treatment is known as convalescent plasma (CCP) therapy. Methods: Plasma units from 1555 consented healthy blood bank donors were collected from February to September 2021. Blood units were tested for the quantitative determination of Immunoglobulin G (IgG) antibodies to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus using one of the following assays based on the availability of the kits: The LIAISON® SARS-CoV-2 TrimericS IgG assay or the Abbott SARS-CoV-2 IgG II Quant assay. Results: Among the tested donors, 1027 participants tested positive for neutralizing anti-SARS-CoV-2 IgG antibodies (66.04%). There were 484 donors whose plasma qualified to be used for CCP therapy (47.13%) and 214 CCP units were stored in the COVID-19 convalescent biobank. Conclusion: We were able to identify and store 214 fresh frozen plasma units qualified for CCP-plasma therapy for COVID-19 patients according to World Health Organization standards. Hence, we established the first COVID-19-convalescent plasma data and plasma biobank for treating COVID-19-infected cancer patients in Jordan and the region.


Тема - темы
COVID-19 , SARS-CoV-2 , Humans , COVID-19/therapy , Antibodies, Viral , Jordan , Biological Specimen Banks , Antibodies, Neutralizing , Blood Donors , Immunoglobulin G , Plasma
11.
Eur J Cancer ; 171: 143-149, 2022 08.
Статья в английский | MEDLINE | ID: covidwho-2178267

Реферат

INTRODUCTION: The protective role against SARS-CoV-2 infection by the third booster dose of mRNA vaccines in cancer patients with solid malignancies is presently unknown. We prospectively investigated the occurrence of COVID-19 in cancer patients on active therapy after the booster vaccine dose. METHODS: Cancer patients on treatment at the Center for Immuno-Oncology (CIO) of the University Hospital of Siena, Italy, and health care workers at CIO who had received a booster third dose of mRNA vaccine entered a systematic follow-up monitoring period to prospectively assess their potential risk of SARS-CoV-2 infection. Serological and microneutralization assay were utilized to assess levels of anti-spike IgG, and of neutralizing antibodies to the SARS-CoV-2 Wild Type, Delta and Omicron variants, respectively, after the booster dose and after negativization of the nasopharyngeal swab for those who had developed COVID-19. RESULTS: Ninety cancer patients with solid tumors on active treatment (Cohort 1) and 30 health care workers (Cohort 2) underwent a booster third dose of mRNA vaccine. After the booster dose, the median value of anti-spike IgG was higher (p = 0.009) in patients than in healthy subjects. Remarkably, 11/90 (12%) patients and 11/30 (37%) healthy subjects tested positive to SARS-CoV-2 infection during the monitoring period. Similar levels of anti-spike IgG and of neutralizing antibodies against all the investigated variants, with geometric mean titers of neutralizing antibodies against the Omicron being the lowest were detected after the booster dose and after COVID-19 in both Cohorts. CONCLUSIONS: The occurrence of SARS-CoV-2 infection we observed in a sizable proportion of booster-dosed cancer patients and in healthy subjects during the Omicron outbreak indicates that highly specific vaccines against SARS-CoV-2 variants are urgently required.


Тема - темы
COVID-19 Vaccines , COVID-19 , Neoplasms , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Humans , Immunoglobulin G , Neoplasms/therapy , SARS-CoV-2 , Vaccines, Synthetic , Viral Envelope Proteins/genetics , mRNA Vaccines
12.
Rev Esp Quimioter ; 35(6): 538-543, 2022 Dec.
Статья в испанский | MEDLINE | ID: covidwho-2206374

Реферат

OBJECTIVE: Serological tests have been a valuable tool during the SARS-CoV-2 pandemic, supporting molecular methods for detection, and monitoring the immune response, caused by vaccination or by natural infection. Within all these techniques, rapid tests are interesting due to their ease of use, rapid response and low cost. METHODS: Two different immunological techniques were evaluated: Realy Tech and Mikrogen Diagnostik recomLine SARS-CoV-2 IgG. SARS-CoV-2 IgG II Quant antibody test and SARS-CoV-IgG assay, both from Abbott Diagnostics, were used as reference techniques. RESULTS: Mikrogen Diagnostik recomLine SARS-CoV-2 IgG shows the best results (S=0.985; E=0.839). Three techniques offered good positive predictive values, but Realy Tech and Healgen negative predictive values left to be desired. CONCLUSIONS: Mikrogen Diagnostik recomLine SARS-CoV-2 IgG showed good results in the detection of antibodies against SARS-CoV-2 and could be used as an alternative to automated techniques.


Тема - темы
COVID-19 , SARS-CoV-2 , Humans , COVID-19 Testing , COVID-19/diagnosis , Sensitivity and Specificity , Antibodies, Viral , Immunoglobulin G
14.
Anal Bioanal Chem ; 413(22): 5619-5632, 2021 Sep.
Статья в английский | MEDLINE | ID: covidwho-2174032

Реферат

In the face of the COVID-19 pandemic, the need for rapid serological tests that allow multiplexing emerged, as antibody seropositivity can instruct about individual immunity after an infection with SARS-CoV-2 or after vaccination. As many commercial antibody tests are either time-consuming or tend to produce false negative or false positive results when only one antigen is considered, we developed an automated, flow-based chemiluminescence microarray immunoassay (CL-MIA) that allows for the detection of IgG antibodies to SARS-CoV-2 receptor-binding domain (RBD), spike protein (S1 fragment), and nucleocapsid protein (N) in human serum and plasma in less than 8 min. The CoVRapid CL-MIA was tested with a set of 65 SARS-CoV-2 serology positive or negative samples, resulting in 100% diagnostic specificity and 100% diagnostic sensitivity, thus even outcompeting commercial tests run on the same sample set. Additionally, the prospect of future quantitative assessments (i.e., quantifying the level of antibodies) was demonstrated. Due to the fully automated process, the test can easily be operated in hospitals, medical practices, or vaccination centers, offering a valuable tool for COVID-19 serosurveillance. Graphical abstract.


Тема - темы
Antibodies, Viral/blood , COVID-19 Serological Testing/methods , Immunoassay/methods , Immunoglobulin G/blood , SARS-CoV-2/immunology , Antigens, Viral/chemistry , Antigens, Viral/immunology , Automation, Laboratory , Coronavirus Nucleocapsid Proteins/immunology , Humans , Immobilized Proteins/chemistry , Immobilized Proteins/immunology , Immune Sera , Immunoassay/instrumentation , Lab-On-A-Chip Devices , Luminescent Measurements , Phosphoproteins/immunology , Sensitivity and Specificity , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Time Factors
15.
Front Immunol ; 13: 909910, 2022.
Статья в английский | MEDLINE | ID: covidwho-2163010

Реферат

Background: IgG anti-spike (S) antibodies arise after SARS-CoV-2 infection as well as vaccination. Levels of IgG anti-S are linked to neutralizing antibody titers and protection against (re)infection. Methods: We measured IgG anti-S and surrogate neutralizing antibody kinetics against Wild Type (WT) and 4 Variants of Concern (VOC) in health care workers (HCW) 3 and 10 months after natural infection ("infection", n=83) or vaccination (2 doses of BNT162b2) with ("hybrid immunity", n=17) or without prior SARS-CoV-2 infection ("vaccination", n=97). Results: The humoral immune response in the "vaccination" cohort was higher at 3 months, but lower at 10 months, compared to the "infection" cohort due to a faster decline. The "hybrid immunity" cohort had the highest antibody levels at 3 and 10 months with a slower decline compared to the "vaccination" cohort. Surrogate neutralizing antibody levels (expressed as %inhibition of ACE-2 binding) showed a linear relation with log10 of IgG anti-S against WT and four VOC. IgG anti-S corresponding to 90% inhibition ranged from 489 BAU/mL for WT to 1756 BAU/mL for Beta variant. Broad pseudoneutralization predicted live virus neutralization of Omicron BA.1 in 20 randomly selected high titer samples. Conclusions: Hybrid immunity resulted in the strongest humoral immune response. Antibodies induced by natural infection decreased more slowly than after vaccination, resulting in higher antibody levels at 10 months compared to vaccinated HCW without prior infection. There was a linear relationship between surrogate neutralizing activity and log10 IgG anti-S for WT and 4 VOC, although some VOC showed reduced sensitivity to pseudoneutralization.


Тема - темы
Antibodies, Neutralizing , COVID-19 , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , Health Personnel , Humans , Immunoglobulin G , SARS-CoV-2
16.
Front Cell Infect Microbiol ; 12: 960938, 2022.
Статья в английский | MEDLINE | ID: covidwho-2154694

Реферат

Coronavirus disease 2019 (COVID-19) is an extremely contagious illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Early disease recognition of COVID-19 is crucial not only for prompt diagnosis and treatment of the patients, but also for effective public health surveillance and response. The reverse transcription-polymerase chain reaction (RT-PCR) is the most common method for the detection of SARS-CoV-2 viral mRNA and is regarded as the gold standard test for COVID-19. However, this test and those for antibodies (IgM and IgG) and antigens have certain limitations (e.g., by yielding false-negative and false-positive results). We have developed an RNA fluorescence in situ hybridization (FISH) method for high-sensitivity detection of SARS-CoV-2 mRNAs in HEK 293T cell cultures as a model. After transfection of HEK 293T cells with plasmids, Spike (S)/envelope (E) proteins and their mRNAs were clearly detected inside the cells. In addition, hybridization time could be reduced to 2 hours for faster detection when probe concentration was increased. Our approach might thus significantly improve the sensitivity and specificity of SARS-CoV-2 detection and be widely applied for the high-sensitivity single-molecular detection of other RNA viruses (e.g., Middle East respiratory syndrome coronavirus (MERS-CoV), Hepatitis A virus, all influenza viruses, and human immunodeficiency virus (HIV)) in various types of samples including tissue, body fluid, blood, and water. RNA FISH can also be utilized for the detection of DNA viruses (e.g., Monkeypox virus, human papillomavirus (HPV), and cytomegalovirus (CMV)) by detection of their mRNAs inside cells or body fluid.


Тема - темы
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , COVID-19 Testing , Clinical Laboratory Techniques/methods , RNA, Messenger/genetics , In Situ Hybridization, Fluorescence , HEK293 Cells , Immunoglobulin M , Immunoglobulin G , Water
17.
Epidemiol Infect ; 150: e187, 2022 Nov 03.
Статья в английский | MEDLINE | ID: covidwho-2150943

Реферат

The SARS-CoV-2 Omicron variant has increased infectivity and immune escape compared with previous variants, and caused the surge of massive COVID-19 waves globally. Despite a vast majority (~90%) of the population of Santa Fe city, Argentina had been vaccinated and/or had been infected by SARS-CoV-2 when Omicron emerged, the epidemic wave that followed its arrival was by far the largest one experienced in the city. A serosurvey conducted prior to the arrival of Omicron allowed to assess the acquired humoral defences preceding the wave and to conduct a longitudinal study to provide individual-level real-world data linking antibody levels and protection against COVID-19 during the wave. A very large proportion of 1455 sampled individuals had immunological memory against COVID-19 at the arrival of Omicron (almost 90%), and about half (48.9%) had high anti-spike immunoglobulin G levels (>200 UI/ml). However, the antibody titres varied greatly among the participants, and such variability depended mainly on the vaccine platform received, on having had COVID-19 previously and on the number of days elapsed since last antigen exposure (vaccine shot or natural infection). A follow-up of 514 participants provided real-world evidence of antibody-mediated protection against COVID-19 during a period of high risk of exposure to an immune-escaping highly transmissible variant. Pre-wave antibody titres were strongly negatively associated with COVID-19 incidence and severity of symptoms during the wave. Also, receiving a vaccine shot during the follow-up period reduced the COVID-19 risk drastically (15-fold). These results highlight the importance of maintaining high defences through vaccination at times of high risk of exposure to immune-escaping variants.


Тема - темы
COVID-19 , Humans , COVID-19/epidemiology , Argentina/epidemiology , Longitudinal Studies , SARS-CoV-2 , Immunoglobulin G
18.
Virol Sin ; 37(5): 731-739, 2022 Oct.
Статья в английский | MEDLINE | ID: covidwho-2150803

Реферат

Latent varicella-zoster virus (VZV) may be reactivated to cause herpes zoster, which affects one in three people during their lifetime. The currently available subunit vaccine Shingrix™ is superior to the attenuated vaccine Zostavax® in terms of both safety and efficacy, but the supply of its key adjuvant component QS21 is limited. With ionizable lipid nanoparticles (LNPs) that were recently approved by the FDA for COVID-19 mRNA vaccines as carriers, and oligodeoxynucleotides containing CpG motifs (CpG ODNs) approved by the FDA for a subunit hepatitis B vaccine as immunostimulators, we developed a LNP vaccine encapsulating VZV-glycoprotein E (gE) and CpG ODN, and compared its immunogenicity with Shingrix™ in C57BL/6J mice. The results showed that the LNP vaccine induced comparable levels of gE-specific IgG antibodies to Shingrix™ as determined by enzyme-linked immunosorbent assay (ELISA). Most importantly, the LNP vaccine induced comparable levels of cell-mediated immunity (CMI) that plays decisive roles in the efficacy of zoster vaccines to Shingrix™ in a VZV-primed mouse model that was adopted for preclinical studies of Shingrix™. Number of IL-2 and IFN-γ secreting splenocytes and proportion of T helper 1 (Th1) cytokine-expressing CD4+ T cells in LNP-CpG-adjuvanted VZV-gE vaccinated mice were similar to that of Shingrix™ boosted mice. All of the components in this LNP vaccine can be artificially and economically synthesized in large quantities, indicating the potential of LNP-CpG-adjuvanted VZV-gE as a more cost-effective zoster vaccine.


Тема - темы
COVID-19 , Herpes Zoster Vaccine , Herpes Zoster , Viral Envelope Proteins/immunology , Adjuvants, Immunologic , Animals , Antibodies, Viral , Hepatitis B Vaccines , Herpes Zoster/prevention & control , Herpesvirus 3, Human/genetics , Immunoglobulin G , Interleukin-2 , Liposomes , Mice , Mice, Inbred C57BL , Nanoparticles , Oligodeoxyribonucleotides , Vaccines, Attenuated , Vaccines, Subunit
19.
Curr Opin Allergy Clin Immunol ; 21(6): 553-558, 2021 12 01.
Статья в английский | MEDLINE | ID: covidwho-2161180

Реферат

PURPOSE OF REVIEW: To provide an update of the current state of antibody therapy for Severe Acute Respiratory Syndrome Coronavirus 2 infection that has progressed immensely in a very short time period. RECENT FINDINGS: Limited clinical effect of classical passive immunotherapy (plasma therapy, hyperimmune immunoglobulin [IgG] preparations) whereas monoclonal antibody therapy, if initiated early in the disease process, shows promising results. SUMMARY: Although antibody therapy still remains to be fully explored in patients with COVID-19, a combination of IgG monoclonal antibodies against the receptor-binding domain of the spike protein currently appears to provide the best form of antibody therapy, Immunoglobulin A dimers and Immunoglobulin M pentamers also show promising preliminary therapeutic results.


Тема - темы
Antibodies, Monoclonal/therapeutic use , COVID-19/therapy , SARS-CoV-2/immunology , COVID-19/blood , COVID-19/immunology , Clinical Trials as Topic , Humans , Immunization, Passive/methods , Immunoglobulin A/therapeutic use , Immunoglobulin G/therapeutic use , Immunoglobulin M/therapeutic use , Treatment Outcome
20.
Rural Remote Health ; 22(3): 6751, 2022 07.
Статья в английский | MEDLINE | ID: covidwho-2146087

Реферат

INTRODUCTION: Coronavirus disease-19 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic, giving rise to a serious global health threat. Many countries including Greece have seen a two-wave pattern of reported cases, with a first wave in spring and a second in autumn of 2020. METHODS: A cross-sectional seroprevalence study was designed to measure the prevalence of IgG antibodies with a quantitative SARS-CoV-2 IgG lab-based serology test, chemiluminescent microparticle immunoassay, against novel coronavirus in rural areas in Greece after the second pandemic wave. The study was conducted on 29 January 2021 in a rural semi-closed area, the municipality of Deskati, prefecture of western Macedonia in Greece after the second pandemic wave. RESULTS: Sixty-nine participants were included in this study. The present study demonstrated a high prevalence of COVID-19 infection (31 of 69 total participants; 45%) and those who were working in the public sector were at higher risk of COVID-19 infection in comparison to their counterparts in private sector (p=0.05364), (relative risk 2.64; 95% confidence interval 1.001-7.086). CONCLUSION: The study presents data showing a high prevalence of herd immunity for COVID-19 in a semi-closed area in Greece. These findings might help to understand the characteristics of this second wave, the behaviour and danger of SARS-CoV-2 in rural areas in Greece and Europe generally.


Тема - темы
COVID-19 , COVID-19/epidemiology , Cross-Sectional Studies , Greece/epidemiology , Humans , Immunoglobulin G , Prevalence , Rural Population , SARS-CoV-2 , Seroepidemiologic Studies , Workplace
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