RÉSUMÉ
The most preferred method for the detection of foot-and-mouth disease (FMD) viral antigen and identification of viral serotype is the enzyme-linked immunosorbent assay (ELISA). Diagnostic tests with high sensitivity are necessary both to distinguish infected vaccinated animals and execute disease control programs for the identification of the carrier animals. The current strategies for the detection of FMD virus are mainly based on the capture antibody (sandwich) ELISA test. The usage of laying pullets as an animal bioreactor for the production of specific egg yolk antibodies (IgY) has increased in recent years due to its high yield, affinity, low price, and quick production turnover. The present study aimed to produce a concentrated and purified IgY polyclonal antibody to design a capture antibody ELISA kit against the FMD virus (FMDV) serotype A. At first, laying hens were immunized with inactivated FMDV serotype virus, and then, on days 14, 21, and 28 following vaccination, the eggs and sera were collected. Afterward, the IgY polyclonal antibodies were extracted and purified from the chicken egg yolk using a polyethylene glycol 6000-ethanol precipitation procedure. Extracts were filtered, purified by ion exchange chromatography, and dialyzed. The purified IgY concentration, estimated by Bradford assay, confirmed its presence by SDS-PAGE and Western blot and also its specific immune reaction by Ouchterlony double immunodiffusion and Dot blot tests. Moreover, for achieving the optimum concentration of antigen/antibody (sera) in sandwich ELISA, a checkerboard titration test was set up based on indirect ELISA results. Eventually, 119 previously confirmed samples (including 80 positive and 39 negative) by both real-time polymerase chain reaction (quantitative PCR, qPCR) and a commercial ELISA kit were used for evaluation of the sensitivity and accuracy of our developed Capture antibody ELISA kit. In this manner, the sensitivity and specificity of our designed kit were 100% and 98%, respectively. Accordingly, the present developed capture ELISA kit based on IgY had high sensitivity and specificity for FMD virus detection and it could be used in the future for both commercial detecting and serotyping applications.
Sujet(s)
Anticorps antiviraux , Poulets , Test ELISA , Fièvre aphteuse , Immunoglobulines , Maladies de la volaille , Animaux , Test ELISA/médecine vétérinaire , Test ELISA/méthodes , Immunoglobulines/immunologie , Immunoglobulines/analyse , Fièvre aphteuse/diagnostic , Fièvre aphteuse/prévention et contrôle , Fièvre aphteuse/virologie , Anticorps antiviraux/analyse , Anticorps antiviraux/sang , Anticorps antiviraux/immunologie , Maladies de la volaille/diagnostic , Maladies de la volaille/virologie , Virus de la fièvre aphteuse/immunologie , Virus de la fièvre aphteuse/isolement et purification , Sensibilité et spécificité , Jaune d'Åuf/immunologieRÉSUMÉ
The SARS-CoV-2 outbreak has provoked more than 6 million deaths worldwide. The scarcity of effective treatments and its virulence converted the vaccines into an essential tool to face it. The most used vaccines were the mRNA, adenovirus vector, and inactivated whole-virus. However, nowadays, infants aged < 6 months are not eligible for any vaccines against COVID-19, and their immunization relies on passive immunity. In this research, we investigated the humoral and cellular immune response generated on newborns of SARS-CoV-2 vaccinated mothers with mRNA or viral vector (VV) vaccine employing Fourier transformed infrared (FTIR) spectroscopy in saliva samples. For this purpose, saliva samples of newborns and their mothers were collected; the population was divided into two groups, VV and mRNA, which were subdivided into three subgroups: before pregnancy (BP), at the first (FTP) and second (STP) trimesters of pregnancy. The samples were analyzed using FTIR spectroscopy, and the bands associated with the humoral and cellular immune responses, such as IgG, IgA, and IFN-γ were analyzed. The integrated areas were calculated and compared to elucidate the quantity of those immunoglobins and the cytokine. Likewise, the correlation of the humoral and cellular immune response between the newborns and their mothers and the correlation between cellular and humoral immune response was also evaluated. The VV vaccine produced a significant humoral and cellular immune response in newborns and their mothers when they received it at the STP compared with the mRNA vaccine, evidencing statistical significance. However, no correlation was observed between newborns and their mothers when the vaccine was applied in this trimester of pregnancy. When administered BP, the mRNA vaccine generated more humoral immunity in newborns and their mothers. Nevertheless, compared with the VV vaccine, it only showed statistical significance in the mothers, highlighting that IgG showed a moderate positive correlation between the newborns and their mothers.
Sujet(s)
Vaccins contre la COVID-19 , COVID-19 , SARS-CoV-2 , Vaccination , Humains , Femelle , Spectroscopie infrarouge à transformée de Fourier/méthodes , Nouveau-né , COVID-19/prévention et contrôle , COVID-19/immunologie , Grossesse , Vaccination/méthodes , SARS-CoV-2/immunologie , Vaccins contre la COVID-19/immunologie , Adulte , Mères , Anticorps antiviraux/immunologie , Anticorps antiviraux/sang , Anticorps antiviraux/analyse , Immunité humorale , Salive/immunologie , Immunité cellulaire , Immunoglobuline G/sang , Immunoglobuline G/immunologie , Immunoglobuline A/immunologie , Immunoglobuline A/analyse , Interféron gamma/métabolisme , Vaccins à ARNm/immunologieRÉSUMÉ
Dengue virus (DENV) is the most prevalent global arbovirus, exhibiting a high worldwide incidence with intensified severity of symptoms and alarming mortality rates. Faced with the limitations of diagnostic methods, an optical and electrochemical biosystem was developed for the detection of DENV genotypes 1 and 2, using cysteine (Cys), cadmium telluride (CdTe) quantum dots, and anti-DENV antibodies. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), surface plasmon resonance (SPR), atomic force microscopy (AFM), and Fourier transform infrared spectroscopy (FTIR) were employed to characterize the immunosensor. The AFM and SPR results demonstrated discernible topographic and angular changes confirming the biomolecular recognition. Different concentrations of DENV-1 and DENV-2 were evaluated (0.05 × 106 to 2.0 × 106 PFU mL-1), resulting in a maximum anodic shift (ΔI%) of 263.67% ± 12.54 for DENV-1 and 63.36% ± 3.68 for DENV-2. The detection strategies exhibited a linear response to the increase in viral concentration. Excellent linear correlations, with R2 values of 0.95391 for DENV-1 and 0.97773 for DENV-2, were obtained across a broad concentration range. Data analysis demonstrated high reproducibility, displaying relative standard deviation values of 3.42% and 3.62% for Cys-CdTe-antibodyDENV-1-BSA and Cys-CdTe-antibodyDENV-2-BSA systems. The detection limits were 0.34 × 106 PFU mL-1 and 0.02 × 106 PFU mL-1, while the quantification limits were set at 1.49 × 106 PFU mL-1 and 0.06 × 106 PFU mL-1 for DENV-1 and DENV-2, respectively. Therefore, the biosensing apparatus demonstrates analytical effectiveness in viral screening and can be considered an innovative solution for early dengue diagnosis, contributing to global public health.
Sujet(s)
Techniques de biocapteur , Virus de la dengue , Dengue , Tellure , Virus de la dengue/isolement et purification , Virus de la dengue/immunologie , Techniques de biocapteur/méthodes , Tellure/composition chimique , Humains , Dengue/diagnostic , Techniques électrochimiques/méthodes , Techniques électrochimiques/instrumentation , Boîtes quantiques/composition chimique , Résonance plasmonique de surface/méthodes , Cystéine/composition chimique , Composés du cadmium/composition chimique , Anticorps antiviraux/immunologie , Anticorps antiviraux/analyse , Dosage immunologique/méthodes , Dosage immunologique/instrumentation , Limite de détection , Microscopie à force atomiqueRÉSUMÉ
Outbreaks of viral diseases seriously jeopardize people's health and cause huge economic losses. At the same time, virology provides a new perspective for biology, molecular biology and cancer research, and it is important to study the discovered viruses with potential applications. Therefore, the development of immediate and rapid viral detection methods for the prevention and treatment of viral diseases as well as the study of viruses has attracted extensive attention from scientists. With the continuous progress of science and technology, especially in the field of bioanalysis, a series of new detection techniques have been applied to the on-site rapid detection of viruses, which has become a powerful approach for human beings to fight against viruses. In this paper, the latest research progress of rapid point-of-care detection of viral nucleic acids, antigens and antibodies is presented. In addition, the advantages and disadvantages of these technologies are discussed from the perspective of practical application requirements. Finally, the problems and challenges faced by rapid viral detection methods and their development prospects are discussed.
Sujet(s)
Analyse sur le lieu d'intervention , Virus , Humains , Virus/isolement et purification , Virus/génétique , Maladies virales/diagnostic , Antigènes viraux/analyse , Anticorps antiviraux/immunologie , Anticorps antiviraux/analyse , Techniques de biocapteur/méthodes , Systèmes automatisés lit malade , ARN viral/analyse , ARN viral/génétiqueRÉSUMÉ
Mucosal antibodies in the upper respiratory tract are the earliest and most critical responders to prevent respiratory infections, providing an indication for the rapid evaluation of immune protection. Here, we report a microfluidic particle counter that directly visualizes mucosal antibody levels in nasal mucus. The mucosal anti-SARS-CoV-2 spike receptor binding domain (RBD) antibodies in nasal secretions first react with magnetic microparticles (MMPs) and polystyrene microparticles (PMPs) that are surface-modified to form a "MMPs-anti-spike RBD IgG-PMPs" complex when RBD is present. After magnetic separation and loading into the microfluidic particle counter, the free PMPs, which are reduced with increasing anti-spike RBD IgG antibody levels, are trapped by a microfluidic particle dam and accumulate in the trapping channel. A sensitive mode [limit of detection (LOD): 14.0 ng mL-1; sample-to-answer time: 70 min] and an equipment-free rapid mode (LOD: 37.4 ng mL-1; sample-to-answer time: 20 min) were achieved. Eighty-seven nasal secretion (NS) samples from vaccinees were analyzed using our microfluidic particle counter, and the results closely resemble those of the gold-standard enzyme-linked immunosorbent assay (ELISA). The analysis shows that higher antibody levels were found in convalescent volunteers compared to noninfected volunteers. Together, we demonstrate a rapid kit that directly indicates immune status, which can guide vaccine strategy for individuals and the government.
Sujet(s)
Anticorps antiviraux , COVID-19 , SARS-CoV-2 , Glycoprotéine de spicule des coronavirus , Humains , SARS-CoV-2/immunologie , SARS-CoV-2/isolement et purification , Glycoprotéine de spicule des coronavirus/immunologie , Anticorps antiviraux/immunologie , Anticorps antiviraux/analyse , COVID-19/immunologie , COVID-19/diagnostic , COVID-19/virologie , COVID-19/prévention et contrôle , Immunoglobuline G/immunologie , Immunoglobuline G/sang , Laboratoires sur puces , Techniques d'analyse microfluidique/instrumentation , Muqueuse nasale/immunologieRÉSUMÉ
Importance: There is still considerable controversy in the literature regarding the capacity of intramuscular messenger RNA (mRNA) vaccination to induce a mucosal immune response. Objective: To compare serum and salivary IgG and IgA levels among mRNA-vaccinated individuals with or without previous SARS-CoV-2 infection. Design, Setting, and Participants: In this cohort study, SARS-CoV-2-naive participants and those with previous infection were consecutively included in the CoviCompare P and CoviCompare M mRNA vaccination trials and followed up to day 180 after vaccination with either the BNT162b2 (Pfizer-BioNTech) vaccine or the mRNA-1273 (Moderna) vaccine at the beginning of the COVID-19 vaccination campaign (from February 19 to June 8, 2021) in France. Data were analyzed from October 25, 2022, to July 13, 2023. Main Outcomes and Measures: An ultrasensitive digital enzyme-linked immunosorbent assay was used for the comparison of SARS-CoV-2 spike-specific serum and salivary IgG and IgA levels. Spike-specific secretory IgA level was also quantified at selected times. Results: A total of 427 individuals were included in 3 groups: participants with SARS-CoV-2 prior to vaccination who received 1 single dose of BNT162b2 (Pfizer-BioNTech) (n = 120) and SARS-CoV-2-naive individuals who received 2 doses of mRNA-1273 (Moderna) (n = 172) or 2 doses of BNT162b2 (Pfizer-BioNTech) (n = 135). The median age was 68 (IQR, 39-75) years, and 228 (53.4%) were men. SARS-CoV-2 spike-specific IgG saliva levels increased after 1 or 2 vaccine injections in individuals with previous infection and SARS-CoV-2-naive individuals. After vaccination, SARS-CoV-2-specific saliva IgA levels, normalized with respect to total IgA levels, were significantly higher in participants with previous infection, as compared with the most responsive mRNA-1273 (Moderna) recipients (median normalized levels, 155 × 10-5 vs 37 × 10-5 at day 29; 107 × 10-5 vs 54 × 10-5 at day 57; and 104 × 10-5 vs 70 × 10-5 at day 180 [P < .001]). In contrast, compared with day 1, spike-specific IgA levels in the BNT162b2-vaccinated SARS-CoV-2-naive group increased only at day 57 (36 × 10-5 vs 49 × 10-5 [P = .01]). Bona fide multimeric secretory IgA levels were significantly higher in individuals with previous infection compared with SARS-CoV-2-naive individuals after 2 antigenic stimulations (median optical density, 0.36 [IQR, 0.16-0.63] vs 0.16 [IQR, 0.10-0.22]; P < .001). Conclusions and Relevance: The findings of this cohort study suggest that mRNA vaccination was associated with mucosal immunity in individuals without prior SARS-CoV-2 infection, but at much lower levels than in previously infected individuals. Further studies are needed to determine the association between specific saliva IgA levels and prevention of infection or transmission.
Sujet(s)
Vaccin ARNm-1273 contre la COVID-19 , Anticorps antiviraux , Vaccin BNT162 , Vaccins contre la COVID-19 , COVID-19 , Immunoglobuline A , Immunoglobuline G , SARS-CoV-2 , Salive , Humains , Mâle , Immunoglobuline G/sang , Femelle , COVID-19/prévention et contrôle , COVID-19/immunologie , SARS-CoV-2/immunologie , Salive/immunologie , Adulte d'âge moyen , Adulte , Immunoglobuline A/analyse , Immunoglobuline A/sang , Anticorps antiviraux/analyse , Anticorps antiviraux/sang , Vaccins contre la COVID-19/immunologie , Vaccins contre la COVID-19/administration et posologie , Vaccination/méthodes , Études de cohortes , Sujet âgé , Immunité muqueuse/immunologie , FranceRÉSUMÉ
Objectives: To investigate specific immunoglobulin A (sIgA), specific immunoglobulin G (sIgG), and neutralizing antibodies (NAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in breast milk and compare immunity in mothers with hybrid immunity (infection and vaccination) versus those solely vaccinated (coronavirus disease [COVID]-naïve). Methods: A longitudinal study was conducted among lactating mothers who received at least two doses of the coronavirus disease 2019 (COVID-19) vaccine or tested positive for SARS-CoV-2. Details of vaccination and infection were collected through questionnaires and interviews. Fifteen milliliters of breast milk samples, self-collected at 1, 3, and 6 months postvaccination or infection, were sent to analysis for sIgA, sIgG, and NAbs using enzyme-linked immunosorbent assay. Results: In total, 119 lactating mothers (202 milk samples) were enrolled; 82 participants had hybrid immunity, and 32 were COVID-19-naïve. Two-thirds received a combination of different vaccines and booster shots. Breast milk retained sIgA, sIgG, and NAbs for up to 6 months post-COVID vaccination or infection. At 3 months, mothers with hybrid immunity had significantly higher sIgA and NAbs compared with COVID-naïve mothers (geometric mean [95% confidence interval (CI)] of sIgA 2.72 [1.94-3.8] vs. 1.44 [0.83-2.48]; NAbs 86.83 [84.9-88.8] vs. 81.28 [76.02-86.9]). No differences in sIgA, sIgG, and NAbs were observed between lactating mothers receiving two, three, or more than or equal to three doses, regardless of hybrid immunity or COVID-naïve status. Conclusion: sIgA, sIgG, and NAbs against SARS-CoV-2 in breast milk sustained for up to 6 months postimmunization and infection. Higher immunity was found in mothers with hybrid immunity. These transferred immunities confirm in vitro protection, supporting the safety of breastfeeding during and after COVID-19 vaccination or infection.
Sujet(s)
Anticorps neutralisants , Anticorps antiviraux , Vaccins contre la COVID-19 , COVID-19 , Lait humain , SARS-CoV-2 , Humains , Femelle , Lait humain/immunologie , COVID-19/prévention et contrôle , COVID-19/immunologie , Vaccins contre la COVID-19/immunologie , Vaccins contre la COVID-19/administration et posologie , Anticorps neutralisants/immunologie , SARS-CoV-2/immunologie , Adulte , Études longitudinales , Anticorps antiviraux/analyse , Anticorps antiviraux/immunologie , Immunoglobuline G/immunologie , Vaccination , Lactation/immunologieRÉSUMÉ
This study explores the correlation between immunological and clinical characteristics in coronavirus disease 2019 (COVID-19) patients with detectable severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in feces, analyzing data from 251 patients admitted to Mostar University Clinical Hospital (UCH) from December 2021 to January 2022. Methods involved reverse transcription quantitative polymerase chain reaction (RT-qPCR) from nasopharyngeal (NP) swabs and feces, alongside serological tests for anti-SARS-CoV-2 spike IgGs. Demographic and clinical data were collected through questionnaires and medical records. The data analyses were performed using SPSS statistical software. Death occurred in 53 patients (21.1%, P < 0.001), mostly in the elderly (47/53, 88.7%, P = 0.001) and immunocompromised (19/53, 35.8%, P = 0.05), particularly those developing acute respiratory insufficiency (ARI) (46/53, 86.8%, P = 0.004), and severe/critical disease (46/53, 86.8%, P = 0.002). Among the patients with positive anti-SARS-CoV-2 IgG antibodies (86/251, 34.3%, P < 0.001), 41 (47.7%) were vaccinated and 45 (52.3%) unvaccinated (P = 0.666), showing no significant differences in clinical outcomes or mortality. Unvaccinated patients with a negative antibody titer had a higher incidence of ARI (96/123, 78%, P = 0.029) and intensive care unit (ICU) admission (22/123, 17.9%, P = 0.026), than those with a positive antibody titer. Forty-seven (62.7%) patients, out of the 75 hospitalized who provided a feces sample, were positive for SARS-CoV-2 RNA (P = 0.028), without statistical differences between fecal SARS-CoV-2 positive and negative groups regarding vaccination status (15/47, 31.9%, P = 0.493), antibody status (18/47, 38.3%, P = 0.628), or death outcome (5/47, 10.6%, P = 0.706). In conclusion, unvaccinated hospitalized patients with a severe COVID-19 presentation and a negative anti-spike SARS-CoV-2 IgG titer had adverse outcomes more frequently. This suggests cautious consideration for the diagnostic use of fecal samples compared to NP swabs.
Sujet(s)
COVID-19 , Fèces , ARN viral , SARS-CoV-2 , Humains , COVID-19/immunologie , COVID-19/virologie , COVID-19/mortalité , COVID-19/diagnostic , COVID-19/épidémiologie , Fèces/virologie , Fèces/composition chimique , Mâle , SARS-CoV-2/immunologie , SARS-CoV-2/génétique , Femelle , Adulte d'âge moyen , Sujet âgé , Pronostic , Adulte , Anticorps antiviraux/sang , Anticorps antiviraux/analyse , Sujet âgé de 80 ans ou plus , Immunoglobuline G/sangRÉSUMÉ
Vaccination against measles is one of the most effective public health interventions which has saved millions of lives and interrupted circulation of the natural virus in the population. However, it is widely accepted that the immunity after vaccination can wane, especially in those who have had no contact with the virus. This study aimed to classify the particular birth cohorts of adults with regard to their exposure to the wild measles virus in the population with a long history of mandatory vaccination. We introduced two methods. In the first, we estimated the probability of exposure to the wild virus through an analysis of antibody levels from the Immunologic Survey performed in the Slovak Republic in 2018, while the second was based on historical epidemiological data. Both methods resulted in similar estimations. Cohorts born in Slovakia before 1964 can be considered to be cohorts in which most people were exposed to the wild measles virus. Cohorts born after 1977 can be designated as cohorts that most likely did not come into the contact with the wild virus. Cohorts born between 1965 and 1976 are composed of a mixture, with a decreasing proportion of people exposed to the wild virus with increasing year of birth. The proposed methods can help identify potential immunity gaps in the adult population. They can be applied in other countries with high measles vaccination coverage to estimate the probability of exposure to the wild measles virus in particular birth cohorts.
Sujet(s)
Virus de la rougeole , Rougeole , Adulte , Humains , Études séroépidémiologiques , Rougeole/épidémiologie , Rougeole/prévention et contrôle , Vaccination , Probabilité , Vaccin contre la rougeole , Anticorps antiviraux/analyseRÉSUMÉ
Influenza B viruses (IBV) cocirculate with influenza A viruses (IAV) and cause periodic epidemics of disease, yet antibody and cellular responses following IBV infection are less well understood. Using the ferret model for antisera generation for influenza surveillance purposes, IAV resulted in robust antibody responses following infection, whereas IBV required an additional booster dose, over 85% of the time, to generate equivalent antibody titers. In this study, we utilized primary differentiated ferret nasal epithelial cells (FNECs) which were inoculated with IAV and IBV to study differences in innate immune responses which may result in differences in adaptive immune responses in the host. FNECs were inoculated with IAV (H1N1pdm09 and H3N2 subtypes) or IBV (B/Victoria and B/Yamagata lineages) and assessed for 72 h. Cells were analyzed for gene expression by quantitative real-time PCR, and apical and basolateral supernatants were assessed for virus kinetics and interferon (IFN), respectively. Similar virus kinetics were observed with IAV and IBV in FNECs. A comparison of gene expression and protein secretion profiles demonstrated that IBV-inoculated FNEC expressed delayed type-I/II IFN responses and reduced type-III IFN secretion compared to IAV-inoculated cells. Concurrently, gene expression of Thymic Stromal Lymphopoietin (TSLP), a type-III IFN-induced gene that enhances adaptive immune responses, was significantly downregulated in IBV-inoculated FNECs. Significant differences in other proinflammatory and adaptive genes were suppressed and delayed following IBV inoculation. Following IBV infection, ex vivo cell cultures derived from the ferret upper respiratory tract exhibited reduced and delayed innate responses which may contribute to reduced antibody responses in vivo.IMPORTANCEInfluenza B viruses (IBV) represent nearly one-quarter of all human influenza cases and are responsible for significant clinical and socioeconomic impacts but do not pose the same pandemic risks as influenza A viruses (IAV) and have thus received much less attention. IBV accounts for greater severity and deaths in children, and vaccine efficacy remains low. The ferret can be readily infected with human clinical isolates and demonstrates a similar course of disease and immune responses. IBV, however, generates lower antibodies in ferrets than IAV following the challenge. To determine whether differences in initial innate responses following infection may affect the development of robust adaptive immune responses, ferret respiratory tract cells were isolated, infected with IAV/IBV, and compared. Understanding the differences in the initial innate immune responses to IAV and IBV may be important in the development of more effective vaccines and interventions to generate more robust protective immune responses.
Sujet(s)
Immunité acquise , Cellules épithéliales , Furets , Immunité innée , Virus de la grippe A , Virus influenza B , Interférons , Muqueuse nasale , Animaux , Enfant , Humains , Anticorps antiviraux/analyse , Anticorps antiviraux/biosynthèse , Anticorps antiviraux/immunologie , Modèles animaux de maladie humaine , Cellules épithéliales/cytologie , Cellules épithéliales/immunologie , Cellules épithéliales/virologie , Furets/immunologie , Furets/virologie , Virus de la grippe A/classification , Virus de la grippe A/croissance et développement , Virus de la grippe A/immunologie , Sous-type H1N1 du virus de la grippe A/immunologie , Sous-type H3N2 du virus de la grippe A/immunologie , Virus influenza B/classification , Virus influenza B/croissance et développement , Virus influenza B/immunologie , Vaccins antigrippaux , Grippe humaine/virologie , Interférons/immunologie , Muqueuse nasale/cytologie , Muqueuse nasale/immunologie , Muqueuse nasale/virologie , Lymphopoïétine stromale thymique/génétique , Lymphopoïétine stromale thymique/immunologie , Cellules cultivéesRÉSUMÉ
BACKGROUND: While the presence of SARS-CoV-2 in human breast milk is contentious, anti-SARS-CoV-2 antibodies have been consistently detected in human breast milk. However, it is uncertain when and how long the antibodies are present. METHODS: This was a prospective cohort study including all consecutive pregnant women with confirmed SARS-CoV-2 infection during pregnancy, recruited at six maternity units in Spain and Hong Kong from March 2020 to March 2021. Colostrum (day of birth until day 4 postpartum) and mature milk (day 7 postpartum until 6 weeks postpartum) were prospectively collected, and paired maternal blood samples were also collected. Colostrum samples were tested with rRT-PCR-SARS-CoV-2, and skimmed acellular milk and maternal sera were tested against SARS-CoV-2 specific immunoglobulin M, A, and G reactive to receptor binding domain of SARS-CoV-2 spike protein 1 to determine the presence of immunoglobulins. Then, we examined how each immunoglobulin type in the colostrum was related to the time of infection by logistic regression analysis, the concordance between these immunoglobulins in the colostrum, maternal serum, and mature milk by Cohen's kappa statistic, and the relationship between immunoglobulin levels in mature milk and colostrum with McNemar. RESULTS: One hundred eighty-seven pregnant women with confirmed SARS-CoV-2 infection during pregnancy or childbirth were recruited and donated the milk and blood samples. No SARS-CoV-2 was found in the human breast milk. Immunoglobulin A, G, and M were present in 129/162 (79·6%), 5/163 (3·1%), and 15/76 (19·7%) colostrum samples and in 17/62 (27·42%), 2/62 (3·23%) and 2/62 (3·23%) mature milk samples, respectively. Immunoglobulin A was the predominant immunoglobulin found in breast milk, and its levels were significantly higher in the colostrum than in the mature milk (p-value < 0.001). We did not find that the presence of immunoglobulins in the colostrum was associated with their presence in maternal, the severity of the disease, or the time when the infection had occurred. CONCLUSIONS: Since anti-SARS-CoV-2 antibodies are found in the colostrum irrespective of the time of infection during pregnancy, but the virus itself is not detected in human breast milk, our study found no indications to withhold breastfeeding, taking contact precautions when there is active disease.
Sujet(s)
COVID-19 , Complications infectieuses de la grossesse , Glycoprotéine de spicule des coronavirus , Humains , Femelle , Grossesse , Lait humain/composition chimique , Allaitement naturel , Études prospectives , SARS-CoV-2 , Anticorps antiviraux/analyse , Immunoglobuline A/analyseRÉSUMÉ
OBJECTIVE: The purpose of this case study was to describe the transmission of porcine reproductive and respiratory syndrome virus (PRRSV) under field and experimental conditions via the consumption of PRRSV-positive swine feed. ANIMALS: 1 domestic swine breeding herd and 20 laboratory-maintained experimental domestic pigs. CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES: A 2,500-sow PRRSV-naïve biosecure breeding herd became infected during the autumn months. It experienced a feed outage involving a specific bin on October 23 (day 0), with the bin refilled on October 24 (day 1). From October 28 to 30 (days 5 to 7), signs of anorexia and hyperemia were observed in 30 gestating sows after consuming feed from this bin. On November 1 (day 9), blood samples from 10 affected sows were PRRSV positive by reverse transcriptase PCR. In contrast, sows in the same room that had consumed feed from other bins were clinically normal and PRRSV negative. To investigate whether the feed delivery introduced PRRSV to the herd, on November 2 (day 10) 4 samples of feed material from the interior walls of the index bin were collected and tested by reverse transcriptase PCR. TREATMENT AND OUTCOME: All 4 samples were positive for PRRSV RNA with cycle threshold values ranging from 26 to 29. Nucleic acid sequencing indicated that the open reading frame 5 region of the PRRSV in feed samples was 100% homologous to PRRSV from index cases. To assess viability of the virus, PRRSV-naïve pigs were allowed to consume the index feed bin samples and became infected with PRRSV based on viral RNA in oral fluid samples, clinical signs, and postmortem lesions. CLINICAL RELEVANCE: These results suggest that feed was a likely source of PRRSV introduction to the herd. This is the first report of PRRSV transmission through feed.
Sujet(s)
Syndrome dysgénésique et respiratoire porcin , Virus du syndrome respiratoire et reproducteur porcin , Maladies des porcs , Suidae , Animaux , Femelle , Virus du syndrome respiratoire et reproducteur porcin/génétique , Sus scrofa/génétique , ARN viral , Consommation alimentaire , Anticorps antiviraux/analyseSujet(s)
Anticorps antiviraux , Virus de la variole simienne , Orthopoxvirose simienne , Humains , Anticorps antiviraux/analyse , Anticorps antiviraux/immunologie , Virus de la variole simienne/immunologie , Vaccination , Orthopoxvirose simienne/immunologie , Orthopoxvirose simienne/prévention et contrôleSujet(s)
Anticorps neutralisants , Anticorps antiviraux , COVID-19 , Muqueuse , SARS-CoV-2 , Humains , Anticorps neutralisants/analyse , Anticorps neutralisants/sang , Anticorps antiviraux/analyse , Anticorps antiviraux/sang , Muqueuse/immunologie , SARS-CoV-2/génétique , SARS-CoV-2/immunologie , COVID-19/sang , COVID-19/génétique , COVID-19/immunologie , COVID-19/virologieRÉSUMÉ
Bovine ephemeral fever virus (BEFV) is a globally spread arthropod-borne RNA virus that has significant economic impacts on the cattle industry. A live attenuated commercial BEF vaccine, based on the Australian BEFV strain 919, is widely used in Israel and other countries. A previous study has suggested the high effectiveness of this vaccine (ULTRAVAC BEF VACCINE™ from Zoetis®), but anecdotal reports of high BEF morbidity among vaccinated dairy herds in Israel casted doubt on these findings. To resolve this uncertainty, a randomized controlled field vaccine effectiveness study was conducted in Israel during a BEF outbreak which occurred in 2021. Eleven dairy herds were enrolled and monitored for BEF-associated morbidity and rumination alteration patterns using electronic monitoring tags (HR Tags, SCR® Dairy, Netanya, Israel). Four of the herds were naturally infected with BEFV during the outbreak, resulting in a total of 120 vaccinated and 311 unvaccinated subjects that were included in the effectiveness study. A mixed-effect Cox proportional hazard regression model was used to calculate the overall hazard ratio between vaccinated and unvaccinated cattle. This analysis demonstrated an average vaccine effectiveness of 60â¯% (95â¯% CI = 38â¯%-77â¯%) for preventing clinical disease. In addition, a non-statistically significant trend (p = 0.1) towards protection from mortality was observed, with no observation of mortality among the vaccinated groups compared to 2.61â¯% mortality (7/311) among the unvaccinated subjects. One hundred and thirty vaccinated and unvaccinated calves from affected and non-affected herds and with different status of morbidity were sampled and analysed by serum-neutralization test. The highest titers of BEFV-neutralizing antibodies were found in subjects that were both vaccinated and clinically affected, indicating a booster effect after vaccination. The results of the study provide evidence for the moderate effectiveness of the ULTRAVAC BEF VACCINE™ for the prevention of BEF.
Sujet(s)
Virus de la fièvre éphémère bovine , Fièvre éphémère bovine , Vaccins antiviraux , Animaux , Bovins , Anticorps antiviraux/analyse , Australie , Épidémies de maladies/prévention et contrôle , Épidémies de maladies/médecine vétérinaire , Fièvre éphémère bovine/épidémiologie , Fièvre éphémère bovine/prévention et contrôle , Virus de la fièvre éphémère bovine/génétique , Israël/épidémiologie , Vaccins atténuésRÉSUMÉ
Objetivos Evaluar la presencia de anticuerpos IgA e IgG específicos del SARS-CoV-2 en lágrima de sujetos no vacunados y vacunados contra la COVID-19 con antecedentes de infección SARS-CoV-2. Correlacionar los resultados en lágrima con los de saliva y sangre, datos clínicos y regímenes de vacunación. Métodos Estudio transversal que incluyó a sujetos con antecedentes de infección SARS-CoV-2, tanto no vacunados como vacunados contra la COVID-19. Se recogieron 3muestras: lágrima, saliva y sangre. Se analizaron IgA e IgG frente a S-1 SARS-CoV-2 con ELISA semicuantitativo. Resultados Treinta sujetos, con una edad media 36,4±10, varones 13/30 (43,3%) con historia de infección SARS-CoV-2 leve; 13/30 (43,3%) habían recibido un régimen de 2 dosis y 13/30 (43,3%) un régimen de 3 dosis de vacunación anti-COVID-19, 4/30 (13,3%) no estaban vacunados. Todos los sujetos con vacunación completa presentaron IgA detectable en los 3biofluidos. Entre los no vacunados, se detectó IgA en 3/4 sujetos en lágrima y saliva, mientras que no se detectó IgG. No se observaron diferencias entre la pauta de vacunación de 2 y 3 dosis según los títulos IgA-IgG. Conclusiones Anticuerpos IgA e IgG del SARS-CoV-2 están presentes en lágrimas de pacientes con antecedentes de COVID-19 leve, lo que destaca el papel de la superficie ocular como primera línea de defensa frente a la infección. La mayoría de los sujetos no vacunados presentaron IgA a largo plazo en lágrima y saliva. La inmunización híbrida (infección natural más vacunación) parece potenciar las respuestas IgG mucosas y sistémicas. No se observaron diferencias entre la pauta de 2 y 3 dosis (AU)
Purpose To evaluate the presence of SARS-CoV-2 specific IgA and IgG antibodies in tears of unvaccinated and anti-COVID-19 vaccinated subjects with previous history of SARS-CoV-2 infection. To compare results in tears with those in saliva and serum and correlate with clinical data and vaccination regimens. Methods Cross-sectional study including subjects with a previous history of SARS-CoV-2 infection, both unvaccinated and vaccinated against COVID-19. Three samples were collected: tears, saliva and serum. IgA and IgG antibodies against S-1 protein of SARS-CoV-2 were analyzed with a semi-quantitative ELISA. Results Thirty subjects, mean age 36.4±10, males 13/30 (43.3%) with history of mild SARS-CoV-2 infection were included. 13/30 (43.3%) subjects had received a 2-dose regimen and 13/30 (43.3%) a 3-dose regimen of anti-COVID-19 vaccine, 4/30 (13.3%) subjects were unvaccinated. All the participants with full anti-COVID-19 vaccination (2-or 3-doses) presented detectable anti-S1 specific IgA in all 3biofluids, tears, saliva and serum. Among unvaccinated subjects, specific IgA was detected in 3/4 subjects in tears and saliva, whereas IgG was not detected. Considering IgA and IgG antibodies titers, no differences were observed between the 2- and 3-dose vaccination regimen. Conclusions SARS-CoV-2-specific IgA and IgG antibodies were detected in tears after mild COVID-19, highlighting the role of the ocular surface as a first line of defense against infection. Most naturally infected unvaccinated individuals exhibit long-term specific IgA in tears and saliva. Hybrid immunization (natural infection plus vaccination) appears to enhance mucosal and systemic IgG responses. However, no differences were observed between the 2- and 3-dose vaccination schedule (AU)
Sujet(s)
Humains , Mâle , Femelle , Adulte , Adulte d'âge moyen , Anticorps antiviraux/analyse , Infections à coronavirus/diagnostic , Infections à coronavirus/immunologie , Larmes/virologie , Immunoglobuline A/analyse , Immunoglobuline G/analyse , Test ELISA , Études transversalesRÉSUMÉ
Coronavirus disease (COVID-19) has generated interest in the assessment of systemic immune status, but existing knowledge about mucosal immunity is clearly insufficient to understand the full pathogenetic mechanisms of the disease. The aim of this study was to evaluate the long-term effects of novel coronavirus infection on mucosal immunity in the postinfection period among health care workers (HCWs). A total of 180 health care workers with and without a history of COVID-19 who ranged in age from 18 to 65 years were enrolled in this one-stage, cross-sectional study. The study subjects completed the 36-Item Short Form (36) Health Survey (SF-36) and the Fatigue Assessment Scale. Secretory immunoglobulin A (sIgA) and total immunoglobulin G (IgG) levels were quantified in saliva samples, induced sputum samples, and nasopharyngeal and oropharyngeal scrapings by an enzyme-linked immunosorbent assay. Specific anti-SARS-CoV-2 IgG antibodies were quantified in serum samples by chemiluminescence immunoassay. Analysis of the questionnaire data showed that all HCWs with a history of COVID-19 reported health problems that limited their daily activities and negative changes in their emotional health three months after the disease, regardless of its severity. The following shifts were detected in the adaptive arm of the immune response in different mucosal compartments. Among subjects who had severe or moderate-to-severe COVID-19, salivary sIgA levels were significantly higher than those in the control group (p < 0.05 and p < 0.005, respectively). Compared to the subjects in the control group, all subjects with prior COVID-19 had significantly higher levels of total IgG in induced sputum. In the group of patients who had had severe infection, total IgG in saliva was also higher (p < 0.05). A direct statistically significant correlation was also detected between the levels of total IgG in all studied samples and the levels of specific IgG antibodies against SARS-CoV-2 in the serum. A significant correlation was observed between total IgG levels and the parameters of physical and social activities, mental health, and fatigue levels. Our study demonstrated long-term changes in the humoral mucosal immune response, which were most pronounced in health care workers with a history of severe or moderate-to-severe COVID-19, and an association of these changes with certain clinical signs of post-COVID-19 syndrome.
Sujet(s)
COVID-19 , Personnel de santé , Immunité muqueuse , Russie , COVID-19/immunologie , COVID-19/anatomopathologie , COVID-19/physiopathologie , Humains , Jeune adulte , Adulte , Adulte d'âge moyen , Immunoglobuline A/analyse , Appareil respiratoire/immunologie , Anticorps antiviraux/analyse , Indice de gravité de la maladie , Immunoglobuline G/analyse , SARS-CoV-2/physiologieRÉSUMÉ
Avian infectious bronchitis (IB) is a highly contagious disease caused by infectious bronchitis virus (IBV). Vaccination is an effective approach for controlling IBV. Therefore, reliable immune monitoring for IB is critical for poultry. In this study, a novel peptide derived from S2 protein was used to develop an enzyme-linked immunosorbent assay (ELISA) for the detection of broadly cross-reactive antibodies against IBV. The peptide-based ELISA (pELISA) showed good specificity and sensitivity in detecting IBV antibodies against different serotypes. A semilogarithmic regression method for determining IBV antibody titers was also established. Antibody titers detected by pELISA and calculated with this equation were statistically similar to those evaluated by indirect fluorescence assay (IFA). Moreover, the comparison analysis showed a 96.07% compatibility between the pELISA and IDEXX ELISA. All these data demonstrate that the pELISA generated here can be as a rapid and reliable serological surveillance tool for monitoring IBV infection or vaccination.
Sujet(s)
Infections à coronavirus , Virus de la bronchite infectieuse , Maladies de la volaille , Animaux , Poulets , Anticorps antiviraux/analyse , Test ELISA/médecine vétérinaire , Test ELISA/méthodes , Infections à coronavirus/diagnostic , Infections à coronavirus/prévention et contrôle , Infections à coronavirus/médecine vétérinaire , Peptides , Maladies de la volaille/diagnostic , Maladies de la volaille/prévention et contrôleRÉSUMÉ
BACKGROUND: Detection of SARS-CoV-2 antibodies is essential in establishing the parameters of an individual's immune response to COVID-19, from both natural infection and vaccination. Despite this, there is currently limited clinical guidance or recommendations for serological methods for their measurement. Here, we evaluate and compare four Luminex-based assays for the multiplex detection of IgG SARS-CoV-2 antibodies. METHODS: The four assays tested were Magnetic Luminex Assay, MULTICOV-AB Assay, Luminex xMAP SARS-CoV-2 Multi-Antigen IgG Assay and LABScreen COVID Plus Assay. Each assay's ability to detect antibodies to SARS-CoV-2 Spike (S), Nucleocapsid (N) and Spike-Receptor Binding Domain (RBD) was evaluated using 50 test samples (25 positive, 25 negative), previously tested by a widely used ELISA technique. RESULTS: The MULTICOV-AB Assay had the highest clinical performance detecting antibodies to S trimer and RBD in 100% (n = 25) of known positive samples. Both the Magnetic Luminex Assay and LABScreen COVID Plus Assay showed significant diagnostic accuracy with sensitivities of 90% and 88% respectively. The Luminex xMAP SARS-CoV-2 Multi-Antigen IgG Assay demonstrated limited detection of antibodies to the S antigen resulting in a sensitivity of 68%. CONCLUSION: Luminex-based assays provide a suitable serological method for multiplex detection of SARS-CoV-2 specific antibodies, with each assay able to detect antibodies to a minimum of 3 different SARS-CoV-2 antigens. Assay comparison identified there is moderate performance variability between manufacturers and further inter-assay variation of antibodies detected to different SARS-CoV-2 antigens.
Sujet(s)
COVID-19 , Humains , COVID-19/diagnostic , SARS-CoV-2 , Sensibilité et spécificité , Anticorps antiviraux/analyse , Immunoglobuline GRÉSUMÉ
Bovine Coronavirus (BCoV) is a major pathogen associated with neonatal calf diarrhea. Standard practice dictates that to prevent BCoV diarrhea, dams should be immunized in the last stage of pregnancy to increase BCoV-specific antibody (Ab) titers in serum and colostrum. For the prevention to be effective, calves need to suck maternal colostrum within the first six to twelve hours of life before gut closure to ensure a good level of passive immunity. The high rate of maternal Ab transfer failure resulting from this process posed the need to develop alternative local passive immunity strategies to strengthen the prevention and treatment of BCoV diarrhea. Immunoglobulin Y technology represents a promising tool to address this gap. In this study, 200 laying hens were immunized with BCoV to obtain spray-dried egg powder enriched in specific IgY Abs to BCoV on a large production scale. To ensure batch-to-batch product consistency, a potency assay was statistically validated. With a sample size of 241, the BCoV-specific IgY ELISA showed a sensitivity and specificity of 97.7% and 98.2%, respectively. ELISA IgY Abs to BCoV correlated with virus-neutralizing Ab titers (Pearson correlation, R2 = 0.92, p < 0.001). Most importantly, a pilot efficacy study in newborn calves showed a significant delay and shorter duration of BCoV-associated diarrhea and shedding in IgY-treated colostrum-deprived calves. Calves were treated with milk supplemented with egg powder (final IgY Ab titer to BCoV ELISA = 512; VN = 32) for 14 days as a passive treatment before a challenge with BCoV and were compared to calves fed milk with no supplementation. This is the first study with proof of efficacy of a product based on egg powder manufactured at a scale that successfully prevents BCoV-associated neonatal calf diarrhea.