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1.
Frontiers of Medicine ; (4): 93-101, 2022.
Article in English | WPRIM | ID: wpr-929197

ABSTRACT

Inducing durable and effective immunity against severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) via vaccination is essential to combat the current pandemic of coronavirus disease 2019 (COVID-19). It has been noticed that the strength of anti-COVID-19 vaccination-induced immunity fades over time, which calls for an additional vaccination regime, as known as booster immunization, to restore immunity among previously vaccinated populations. Here we report a pilot open-label trial of a third dose of BBIBP-CorV, an inactivated SARS-CoV-2 vaccine (Vero cell), on 136 participants aged between 18 to 63 years. Safety and immunogenicity in terms of neutralizing antibody titers and cytokine/chemokine responses were analyzed as the main endpoint until day 28. While systemic reactogenicity was either absent or mild, SARS-CoV-2-specific neutralizing antibody titers rapidly arose in all participants within 4 weeks, surpassing the peak antibody titers elicited by the initial two-dose immunization regime. Broad increases of cellular immunity-associated cytokines and chemokines were also detected in the majority of participants after the third vaccination. Furthermore, in an exploratory study, a newly developed recombinant protein vaccine, NVSI-06-08 (CHO Cells), was found to be safe and even more effective than BBIBP-CorV in eliciting humoral immune responses in BBIBP-CorV-primed individuals. Together, these results indicate that a third immunization schedule with either homologous or heterologous vaccine showed favorable safety profiles and restored potent SARS-CoV-2-specific immunity, providing support for further trials of booster vaccination in larger populations.


Subject(s)
Adolescent , Adult , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , China , Humans , Immunogenicity, Vaccine , Middle Aged , SARS-CoV-2 , Vaccination , Young Adult
2.
Chinese Journal of Biotechnology ; (12): 1981-1993, 2022.
Article in Chinese | WPRIM | ID: wpr-927832

ABSTRACT

The aim of this study was to develop a semi-quantitative immunochromatographic method for rapid detection of Newcastle disease virus (NDV) antibodies by expressing HN protein in rice endosperm bioreactor. The recombinant plasmid pUC57-HN was digested by MlyⅠ and XhoⅠ to retrieve the HN gene, while the intermediate vector pMP3 containing promoter, signal peptide and terminator was digested by NaeⅠ and XhoⅠ. The HN gene and the linearized pMP3 were purified and ligated to form a recombinant plasmid pMP3-HN1. Subsequently, pMP3-HN1 and plant vector pCAMBIA1300 were digested by EcoRⅠ and Hind Ⅲ, and the HN1 gene was cloned into pCAMBIA1300. The recombinant plasmid pCAMBIA1300-HN1 was introduced into Agrobacterium tumefaciens EHA105 by electrotransformation, and the pCAMBIA1300-HN1 was transferred into rice callus by agrobacterium-mediated method. After dark culture, callus screening, differentiation, rooting and transplanting, transgenic rice seeds were obtained 4 months later. PCR identified that the HN gene has been inserted into the rice genome. SDS-PAGE and Western blotting indicated that the HN protein was successfully expressed in the positive rice endosperm. The purity of the HN protein was more than 90% by SP cation exchange chromatography and gel filtration chromatography. According to the national standards for the diagnostic techniques of Newcastle disease HI test (HI≥4log2, positive antibody reaction), a colloidal gold labeled purified HN protein was used to prepare a semi-quantitative test strip by double-antibody sandwich method for rapid detection of NDV antibody. The results showed that the test strip did not cross-react with positive sera against other viruses, and the sensitivity of the test strip reached 1:102 400 for standard positive sera of Newcastle disease. Testing of a total of 308 clinical sera showed that the compliance rate of the test strip with HI test was 97.08%, and the Kappa value was 0.942. In conclusion, high purity recombinant HN protein was obtained from rice endosperm, and a simple, rapid, highly sensitive and highly specific semi-quantitative immunochromatographic strip was developed. The test strip could be used for immune evaluation of the Newcastle disease vaccine.


Subject(s)
Animals , Antibodies, Viral , Chickens , HN Protein/metabolism , Newcastle Disease/prevention & control , Newcastle disease virus/metabolism , Oryza/genetics
3.
Chinese Journal of Biotechnology ; (12): 1824-1836, 2022.
Article in Chinese | WPRIM | ID: wpr-927820

ABSTRACT

In order to construct a recombinant replication deficient human type 5 adenovirus (Ad5) expressing a foot-and-mouth disease virus (FMDV) capsid protein, specific primers for P12A and 3B3C genes of FMDV-OZK93 were synthesized. The P12A and 3B3C genes were then amplified and connected by fusion PCR, and a recombinant shuttle plasmid pDC316-mCMV-EGFP-P12A3B3C expressing the FMDV-OZK93 capsid protein precursor P12A and 3B3C protease were obtained by inserting the P12A3B3C gene into the pDC316-mCMV-EGFP plasmid. The recombinant adenovirus rAdv-P12A3B3C-OZK93 was subsequently packaged, characterized and amplified using AdMaxTM adenovirus packaging system, and the expression was verified by infecting human embryonic kidney cell HEK-293. The humoral and cellular immunity levels of well-expressed and purified recombinant adenovirus immunized mice were evaluated. The results showed that rAdv-P12A3B3C-OZK93 could be stably passaged and the maximum virus titer reached 1×109.1 TCID50/mL. Western blotting and indirect immunofluorescence showed that rAdv-P12A3B3C-OZK93 expressed the FMDV-specific proteins P12A and VP1 in HEK-293 cells. In addition, the PK cell infection experiment confirmed that rAdv-P12A3B3C-OZK93 could infect porcine cells, which is essential for vaccination in pigs. Comparing with the inactivated vaccine group, the recombinant adenovirus could induce higher FMDV-specific IgG antibodies, γ-IFN and IL-10. This indicates that the recombinant adenovirus has good immunity for animal, which is very important for the subsequent development of foot-and-mouth disease vaccine.


Subject(s)
Adenoviridae/genetics , Adenoviruses, Human/genetics , Animals , Antibodies, Viral , Capsid/metabolism , Capsid Proteins , Foot-and-Mouth Disease/prevention & control , Foot-and-Mouth Disease Virus/genetics , HEK293 Cells , Humans , Mice , Recombinant Proteins/genetics , Serogroup , Swine , Viral Proteins , Viral Vaccines/genetics
4.
Chinese Journal of Biotechnology ; (12): 160-173, 2022.
Article in Chinese | WPRIM | ID: wpr-927701

ABSTRACT

The conserved hemagglutinin (HA) stem region of avian influenza virus (AIV) is an important target for designing broad-spectrum vaccines, therapeutic antibodies and diagnostic reagents. Previously, we obtained a monoclonal antibody (mAb) (5D3-1B5) which was reactive with the HA stem epitope (aa 428-452) of H7N9 subtype AIV. To systematically characterize the mAb, we determined the antibody titers, including the HA-binding IgG, hemagglutination-inhibition (HI) and virus neutralizing (VN) titers. In addition, the antigenic epitope recognized by the antibody as well as the sequence and structure of the antibody variable region (VR) were also determined. Moreover, we evaluated the cross-reactivity of the antibody with influenza virus strains of different subtypes. The results showed that the 5D3-1B5 antibody had undetectable HI and VN activities against H7N9 virus, whereas it exhibited strong reactivity with the HA protein. Using the peptide-based enzyme-linked immunosorbent assay and biopanning with a phage-displayed random peptide library, a motif with the core sequence (431W-433Y-437L) in the C-helix domain in the HA stem was identified as the epitope recognized by 5D3-1B5. Moreover, the mAb failed to react with the mutant H7N9 virus which contains mutations in the epitope. The VR of the antibody was sequenced and the complementarity determining regions in the VR of the light and heavy chains were determined. Structural modeling and molecular docking analysis of the VR verified specific binding between the antibody and the C-helix domain of the HA stem. Notably, 5D3-1B5 showed a broad cross-reactivity with influenza virus strains of different subtypes belonging to groups 1 and 2. In conclusion, 5D3-1B5 antibody is a promising candidate in terms of the development of broad-spectrum virus diagnostic reagents and therapeutic antibodies. Our findings also provided new information for understanding the epitope characteristics of the HA protein of H7N9 subtype AIV.


Subject(s)
Animals , Antibodies, Monoclonal , Antibodies, Viral , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Hemagglutinins , Influenza A Virus, H7N9 Subtype , Influenza in Birds , Molecular Docking Simulation
5.
Chinese Journal of Biotechnology ; (12): 130-138, 2022.
Article in Chinese | WPRIM | ID: wpr-927698

ABSTRACT

In order to obtain virus-like particles (VLPs) for prevention of bovine viral diarrhea virus 1 (BVDV-1), the C-Erns-E1-E2 region was cloned into a pFastBacDaul vector for generating the recombinant Bacmid-BVDV-1 in DH10Bac Escherichia coli. The recombinant baculovirus Baculo-BVDV-1 was produced by transfecting the Sf9 cells with Bacmid-BVDV-1. The expressed protein and the assembled VLPs were determined by immunofluorescence, Western blotting and electron microscopy. Guinea pigs were immunized with inactivated VLPs coupled with the Montanide ISA-201 adjuvant. The immunogenicity of VLPs was evaluated by monitoring the humoral immune response with neutralizing antibody titer determination, as well as by analyzing the cell-mediated immune response with lymphocyte proliferation assay. The protective efficacy of VLPs was evaluated by challenging with 106 TCID50 virulent BVDV-1 strain AV69. The results showed that the recombinant Baculo-BVDV-1 efficiently expressed BVDV structural protein and form VLPs in infected Sf9 cells. The immunization of guinea pigs with VLPs resulted in a high titer (1:144) of neutralizing antibody, indicating an activated cellular immunity. Significantly lower viral RNA in the blood of the post-challenged immunized guinea pigs was observed. The successful preparation of BVDV VLPs with insect cell expression system and the observation of the associated immunogenicity may facilitate further development of a VLPs-based vaccine against BVD.


Subject(s)
Animals , Antibodies, Viral , Diarrhea , Diarrhea Virus 1, Bovine Viral , Guinea Pigs , Mineral Oil , Viral Envelope Proteins , Viral Vaccines
6.
Chinese Medical Journal ; (24): 799-805, 2022.
Article in English | WPRIM | ID: wpr-927570

ABSTRACT

BACKGROUND@#The new emerging avian influenza A H7N9 virus, causing severe human infection with a mortality rate of around 41%. This study aims to provide a novel treatment option for the prevention and control of H7N9.@*METHODS@#H7 hemagglutinin (HA)-specific B cells were isolated from peripheral blood plasma cells of the patients previously infected by H7N9 in Jiangsu Province, China. The human monoclonal antibodies (mAbs) were generated by amplification and cloning of these HA-specific B cells. First, all human mAbs were screened for binding activity by enzyme-linked immunosorbent assay. Then, those mAbs, exhibiting potent affinity to recognize H7 HAs were further evaluated by hemagglutination-inhibiting (HAI) and microneutralization in vitro assays. Finally, the lead mAb candidate was selected and tested against the lethal challenge of the H7N9 virus using murine models.@*RESULTS@#The mAb 6-137 was able to recognize a panel of H7 HAs with high affinity but not HA of other subtypes, including H1N1 and H3N2. The mAb 6-137 can efficiently inhibit the HA activity in the inactivated H7N9 virus and neutralize 100 tissue culture infectious dose 50 (TCID50) of H7N9 virus (influenza A/Nanjing/1/2013) in vitro, with neutralizing activity as low as 78 ng/mL. In addition, the mAb 6-137 protected the mice against the lethal challenge of H7N9 prophylactically and therapeutically.@*CONCLUSION@#The mAb 6-137 could be an effective antibody as a prophylactic or therapeutic biological treatment for the H7N9 exposure or infection.


Subject(s)
Animals , Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing/therapeutic use , Antibodies, Viral , Hemagglutinins , Humans , Influenza A Virus, H1N1 Subtype , Influenza A Virus, H3N2 Subtype , Influenza A Virus, H7N9 Subtype , Influenza Vaccines , Influenza in Birds , Influenza, Human/prevention & control , Mice
7.
Medicina (B.Aires) ; 81(5): 683-687, oct. 2021. graf
Article in Spanish | LILACS | ID: biblio-1351038

ABSTRACT

Resumen La rápida propagación del coronavirus SARS-CoV-2, agente causal de la enfermedad pandémica emergente COVID-19 y sus nuevas variantes, requiere del compromiso de la comunidad inmunológica para comprender la magnitud y naturaleza de la respuesta inmunológica adaptativa desarrollada por pacientes recuperados de COVID-19 e individuos vacunados con diferentes estrategias y protocolos, a los fines de imple mentar nuevas políticas sanitarias. En la actualidad, la determinación de la inmunidad contra SARS-CoV-2 se basa principalmente en la detección de anticuerpos específicos y la determinación de su actividad neutralizante. Sin embargo, a pesar de la alta sensibilidad de estos ensayos, un número considerable de pacientes e indivi duos vacunados carecen de respuesta humoral detectable, o evidencian una disminución rápida de la misma en el tiempo. Con el objetivo de estudiar la respuesta inmune celular desencadenada frente a SARS-CoV-2, en nuestro laboratorio desarrollamos la "Plataforma COVID-T" estrategia integral optimizada dirigida a caracte rizar y monitorear la respuesta de linfocitos T específicos de SARS-CoV-2 a partir de muestras de sangre de individuos vacunados y/o recuperados de COVID-19. Esta plataforma permite evaluar la naturaleza, magnitud y persistencia de la inmunidad celular T generada tanto por la infección con SARS-CoV-2, como por distintos esquemas y protocolos de vacunación en diferentes poblaciones de individuos. Asimismo, permite evaluar la respuesta inmunológica T generada frente a nuevas variantes del virus e identificar individuos sanos resistentes a SARS-CoV-2 con inmunidad pre-existente hacia coronavirus estacionales.


Abstract The rapid spread of the SARS-CoV-2, the caus ative agent of the emergent pandemic disease COVID-19, requires the urgent commitment of the immunology community to understand the adaptive immune response developed by COVID-19 convalescent patients and individuals vaccinated with different strategies and schemes, with the ultimate goal of implementing and optimizing health care and prevention policies. Currently, assessment of SARS-CoV-2-specific immunity is mainly focused on the measurement of the antibody titers and analysis of their neutralizing capacity. However, a considerable proportion of individuals lack humoral responses or show a progressive decline of SARS-CoV-2-specific neutral izing antibodies. In order to study the cellular response of convalescent patients and vaccinated individuals, we have developed the 'COVID-T Platform', an optimized strategy to study SARS-CoV-2-specific T cell responses. This platform allows assessment of the nature, magnitude and persistence of antigen-specific T-cell immunity in COVID-19-convalescent patients and vaccinated individuals. Moreover, it gives the opportunity to study cellular responses against emerging coronavirus variants and to identify individuals with cross-reactive immunity against seasonal coronaviruses.


Subject(s)
Humans , SARS-CoV-2 , COVID-19 , T-Lymphocytes , Antibodies, Neutralizing , Antibodies, Viral
8.
Rev. Assoc. Med. Bras. (1992) ; 67(10): 1403-1408, Oct. 2021. tab, graf
Article in English | LILACS | ID: biblio-1351446

ABSTRACT

SUMMARY OBJECTIVE: This study aimed to investigate the seropositivity of CoronaVac-SinoVac vaccination in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) risk factors and comorbidities. METHODS: Immunoglobulin (IgG) antibody responses were examined on the 21st day after the second dose of CoronaVac-SinoVac 6 μg vaccine on the 28th day. SARS-CoV-2 IgG antibody levels were measured by using the enzyme-linked immunosorbent assay method in vaccinated health care workers (n=134) (Group I), vaccinated polymerase chain reaction (PCR) (+) who had coronavirus-19 (COVID-19) disease (n=21) (Group II), and unvaccinated PCR (+) (n=28) (Group III) participants. Subgroups were formed in Group I according to the presence of COVID-19 risk factors and comorbidities (diabetes mellitus, cardiovascular disease, and asthma/allergy) and demographic data. RESULTS: Seropositivity rates were 95.5, 100, and 89.3% for Groups I, II, and III, respectively. IgG antibody levels were found significantly higher in the group between the ages of 20-30 in group I compared to those aged 31-50 and over 50 (both p<0.01). It was found significantly higher in normal-weight individuals than in the overweight and obese group (both p<0.01). IgG antibody levels were found significantly lower in people with cardiovascular disease and diabetes mellitus compared with those who did not (p<0.05 and p<0.001, respectively). There was a negative correlation between IgG antibody response values and body mass index and age in Group I (r= −0.336, p<0.001 and r= −0.307, p<0.001, respectively). CONCLUSION: IgG antibody values decrease with age and with increasing body mass index. The presence of comorbidities (i.e., diabetes mellitus and cardiovascular disease) decreased COVID-19 IgG antibody values.


Subject(s)
Humans , Adult , Young Adult , COVID-19 , Vaccination , COVID-19 Vaccines , SARS-CoV-2 , Antibodies, Viral
9.
Rev. cuba. med ; 60(3): e1383, 2021.
Article in Spanish | LILACS, CUMED | ID: biblio-1347520

ABSTRACT

Introducción: El nuevo coronavirus tiene material genético. Esto permite a un receptor transformarse en el sitio de acción polibásica y es capaz de infectar a través de múltiples receptores de entrada y resaltar a las proteínas de tipo espiga (S). La proteína 'espiga' es una proteína de fusión viral de la Covid-19, es por ello que en la búsqueda terapéutica se establece las siguientes preguntas, ¿la hibridación de anticuerpos logrará ganar la guerra contra la pandemia de la Covid-19?; o ¿el plasma rico en anticuerpos puede mantener a las personas fuera de las unidades de cuidados intensivos? Estas preguntas radican en que los estudios actuales no establecen la verdadera utilidad de la terapia inmunológica. Objetivo: Presentar la utilidad de anticuerpos híbridos ante la actual pandemia de la Covid-19 y otros coronavirus. Métodos: Se desarrolló una revisión bibliográfica a partir de la evidencia existente acerca del panorama de la proteómica en el estudio del sistema inmune para combatir infecciones. Se utilizó un margen de tiempo entre el año 1999 al 2020. Se seleccionaron un total de 37 documentos que cumplen con los protocolos de inclusión en idioma inglés o español; en la búsqueda se utilizaron términos MeSH. Se escogieron estudios de orden observacional o analíticos; de carácter experimental, reporte de casos que dataran aspectos bioquímicos, biológicos, patológicos y clínicos del sistema inmune como blanco terapéutico ante la pandemia actual. El análisis documental fue realizado por el Grupo de Investigación en Salud de la Universidad del Cauca-Popayán, con apoyo y dirección de la Universidad de Houston, Texas (EEUU), con el apoyo de profesorado del Programa de Investigación Humana de la NASA. Resultados: La respuesta positiva para controlar esta pandemia está basada en los cuidados preventivos y en las posibles terapias innovadoras ante los nuevos coronavirus que logren transmitirse de animales a humanos. Se resalta el posible uso de anticuerpos de dominio único híbridos para frenar infecciones víricas nuevas. Conclusiones: Se resalta el posible uso de anticuerpos de dominio único híbridos para frenar infecciones víricas nuevas(AU)


Introduction: The new coronavirus has genetic material. This allows a receptor to transform into the polybasic site of action and it is capable of infecting through multiple entry receptors and highlighting spike-like (S) proteins. The spike protein is a viral fusion protein of Covid-19, which is why in the therapeutic search the following questions are established, will antibody hybridization succeed in winning the war against the Covid-19 pandemic? Or can antibody-rich plasma keep people out of intensive care units? These questions are that current studies do not establish the true utility of immune therapy. Objective: To settle the usefulness of hybrid antibodies to the current Covid-19 pandemic and other coronaviruses. Methods: A bibliographic review was developed from the existing evidence about the panorama of proteomics in the study of the immune system to fight infections. A time frame was used between 1999 and 2020. A total of 37 documents, in English or Spanish, that comply with the inclusion protocols were selected; MeSH terms were used in the search. Observational or analytical studies were chosen; experimental, case report dating biochemical, biological, pathological and clinical aspects of the immune system as a therapeutic target in the current pandemic. The documentary analysis was carried out by the Health Research Group of the Universidad del Cauca-Popayán, with the support and direction of the University of Houston, Texas (USA), with the support of faculty from NASA Human Research Program. Results: The positive response to control this pandemic is based on preventive care and possible innovative therapies for the new coronaviruses that manage to be transmitted from animals to humans. Conclusions: The possible use of hybrid single domain antibodies to stop new viral infections is highlighted(AU)


Subject(s)
Humans , Immunoglobulins/therapeutic use , COVID-19/transmission , Antibodies, Viral/therapeutic use
10.
Medicina (B.Aires) ; 81(2): 135-142, June 2021. graf
Article in English | LILACS | ID: biblio-1287262

ABSTRACT

Abstract Most countries in Latin America have already reported thousands of confirmed cases and vulnerable populations are the most affected by the coronavirus disease 2019 (COVID-19) pandemic. Preventive measures such as hygiene, social distancing, and isolation, essential to stop the spread of coronavirus, are difficult to accomplish for vulnerable populations due to their living conditions. Seroepidemiological surveys are assets to measure the transmission for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Until July 1st, the incidence rate of SARS-CoV-2 infection in Barrio Padre Mugica, one of the largest slums in Buenos Aires City, was 5.9%. This study aimed to establish the prevalence of SARS-CoV-2 antibodies immunoglobulin G (IgG) immediately after the outbreak, and to identify neighbourhood, household and individual factors associated with seroconversion. The prevalence based on IgG was 53.4% (95% CI 52.8% to 54.1%). For each polymerase chain reaction (RT-qPCR) confirmed case, nine people tested IgG positive, indicating a high rate of undetected (probably asymptomatic) infections. Hence, the high rate of undiagnosed people suggests that clinical criteria and epidemiological nexus should be considered. The high seroprevalence observed in the context of an intense epidemic in a vulnerable area might serve as a reference to other countries. This study contributes to future decision making by understanding population immunity against SARS-CoV2 and its relation to living conditions and foccus that comprehensive biosocial, household-level interventions are needed.


Resumen Muchos países de América Latina han informado miles de casos confirmados y las poblaciones vulnerables son las más afectadas por la pandemia de la enfermedad por coronavirus 2019 (COVID-19). Las medidas preventivas como la higiene, el distanciamiento social y el aislamiento, fundamentales para frenar la propagación del coronavirus, son difíciles de lograr en estas poblaciones debido a sus condiciones de vida. Los estudios seroepidemiológicos son de gran utilidad para medir la transmisión del síndrome respiratorio agudo severo coronavirus 2 (SARS-CoV-2). Hasta el 1 de julio, la tasa de incidencia de la infección por SARS-CoV-2 en el Barrio Padre Mugica, uno de los barrios marginales más grandes de la ciudad de Buenos Aires, era del 5.9%. Este estudio tuvo como objetivo estimar la prevalencia de anticuerpos inmunoglobulina G (IgG) para SARS-CoV-2 inmediatamente después del brote, e identificar factores del barrio, hogar e individuales asociados con la seroconversión. La prevalencia basada en IgG fue del 53.4% (IC del 95%: 52.8% a 54.1%). Para cada caso confirmado por reacción en cadena de la polimerasa (RT-qPCR), nueve personas dieron positivo en IgG, lo que indica una alta tasa de infecciones no detectadas y probablemente asintomáticas. La alta tasa de personas no diagnosticadas sugiere que se deben considerar los criterios clínicos y el nexo epidemiológico. La alta seroprevalencia observada en el contexto de una intensa epidemia en una zona vulnerable podría servir de referencia a otros países. Este estudio contribuye a la toma de decisiones futuras al comprender la inmunidad de la población contra el SARS-CoV2 en su relación con las condiciones de vida y por su enfoque en la necesidad de intervenciones integrales a nivel del hogar.


Subject(s)
Humans , Poverty Areas , COVID-19 , RNA, Viral , Seroepidemiologic Studies , SARS-CoV-2 , Antibodies, Viral
11.
Rev. bras. ciênc. vet ; 28(2): 97-101, abr./jun. 2021. il.
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1367729

ABSTRACT

Objetivou-se investigar a presença do Vírus da Estomatite Vesicular (VEV) e seus fatores de risco para ocorrência e disseminação da enfermidade em equídeos das mesorregiões Leste e Oeste Potiguar do estado do Rio Grande do Norte, Brasil. Foram analisadas pela técnica de virusneutralização, 809 amostras sanguíneas de equídeos provenientes de noventa propriedades de dezesseis municípios Potiguares durante os meses de julho de 2018 a fevereiro de 2019. Os fatores de riscos associados ao VEV foram avaliados por meio de questionário epidemiológico e os dados submetidos a análise estatística no programa IBM SPSS Statistics versão 21.0 com nível de confiança de 95%. Posteriormente, todas as variáveis estatisticamente significantes foram submetidas a análise de regressão de Poisson. A soroprevalência de anticorpos anti-VEV foi 24,6% (199/809), sendo 3,2% (13/402) de soropositivos na mesorregião Leste e 45,7% (186/407) na do Oeste Potiguar. Com relação aos sorotipos, observou-se uma prevalência de 3,8% (31/809) e 24,5% (198/809) para Indiana 2 e 3 respectivamente, com 15,1% (30/198) de coinfecção. Equídeos criados na mesorregião Oeste, em propriedades que não realizam quarentena e onde os animais enfermos são mantidos no rebanho, foram consideradas fatores predisponentes a infecção pelo VEV. Esses resultados demonstram a circulação do VEV em equídeos no Rio Grande do Norte, com destaque ao Oeste Potiguar, e sendo necessário a aplicação de medidas sanitárias que impeçam introdução e disseminação do vírus ente as espécies susceptíveis, principalmente em condições climáticas favoráveis para a sua manutenção, no ambiente de criação e pastagens.


This study aimed to investigate the presence of Vesicular stomatitis virus (VSV) and risk factors for its occurrence and dissemination in equines from the Eastern and Western mesoregions of the state of Rio Grande do Norte, Brazil. Blood samples were analyzed, by Serum Virus Neutralization Assay, from 809 animals belonging to 90 properties distributed in sixteen municipalities from July 2018 to February 2019. Risk factors were assessed using an epidemiological questionnaire. Data were submitted to statistical analysis using the software IBM SPSS Statistics, version 21.0 with a 95% confidence level. Also, all statistically significant variables were subjected to Poisson regression analysis. The occurrence of anti-VSV antibodies was 24.6% (199/809) with 3.2% (13/402) and 45.7% (186/407) of seropositivity in the Western and Eastern mesoregion, respectively. Regarding serotypes, there were an occurrence of 3.8% (31/809) and 24.5% (198/809) for Indiana 2 and 3, respectively, and 15.1% (30/198) of co-infection for both. Equines kept of the Western mesoregion, on properties that do not quarantine, and where sick animals are kept in the herd, were considered risk factors for LVV infection. These results demonstrate the presence of VSV in equines in Rio Grande do Norte, with emphasis on Oeste Potiguar, and that sanitary measures must be adopted to prevent the introduction and viral spreading among susceptible species, especially due to favorable climatic conditions for the maintenance of VSV in the breeding and pasture environment.


Subject(s)
Animals , Vesicular stomatitis Indiana virus , Horse Diseases/virology , Risk Factors , Vesicular Stomatitis/virology , Antibodies, Viral/analysis
12.
J. bras. nefrol ; 43(1): 128-132, Jan.-Mar. 2021. tab, graf
Article in English, Portuguese | LILACS | ID: biblio-1154655

ABSTRACT

Abstract Thromboembolic events are frequent in patients with COVID-19 infection, and no cases of bilateral renal infarctions have been reported. We present the case of a 41-year-old female patient with diabetes mellitus and obesity who attended the emergency department for low back pain, respiratory failure associated with COVID-19 pneumonia, diabetic ketoacidosis, and shock. The patient had acute kidney injury and required hemodialysis. Contrast abdominal tomography showed bilateral renal infarction and anticoagulation was started. Kidney infarction cases require high diagnostic suspicion and possibility of starting anticoagulation.


Resumo Fenômenos tromboembólicos são frequentes em pacientes com infecção por COVID-19 e nenhum caso de infarto renal bilateral havia sido relatado. Apresentamos o caso de uma paciente do sexo feminino, de 41 anos, com diabetes mellitus e obesidade, que deu entrada no serviço de urgência por lombalgia, insuficiência respiratória associada à pneumonia COVID-19, cetoacidose diabética e choque. A paciente apresentava lesão renal aguda e demandava hemodiálise. A tomografia abdominal contrastada mostrou infarto renal bilateral e foi iniciada anticoagulação. Os casos de infarto renal requerem alta suspeita diagnóstica e possibilidade de iniciar a anticoagulação.


Subject(s)
Humans , Female , Adult , Diabetes Complications , Acute Kidney Injury/complications , COVID-19/complications , Infarction/complications , Kidney/blood supply , Obesity/complications , Respiratory Insufficiency/complications , Severity of Illness Index , Immunoglobulin M/blood , Tomography, X-Ray Computed , Renal Dialysis/methods , Fatal Outcome , Acute Kidney Injury/therapy , SARS-CoV-2/immunology , COVID-19/drug therapy , COVID-19/virology , Antibodies, Viral/blood , Anticoagulants/therapeutic use
13.
An. bras. dermatol ; 96(1): 88-90, Jan.-Feb. 2021. graf
Article in English | LILACS | ID: biblio-1152790

ABSTRACT

Abstract The authors present a case of dengue fever mimicking rubella. Male patient, in the second episode of dengue fever, presented afebrile, with diffuse morbilliform rash and craniocaudal progression, having subsequently affected his palms and soles. On the third day of clinical evolution, serologies did not indicate IgM, IgG, or NS1, but on the sixth day of evolution, IgM and IgG were reactive for dengue fever. Previous episodes of dengue are a risk factor for the development of more severe conditions, but this was atypical because the patient was afebrile and had a rubelliform rash. The case also illustrates an early IgG anamnestic response, as it was a reinfection.


Subject(s)
Humans , Male , Rubella , Dengue/diagnosis , Immunoglobulin G , Immunoglobulin M , Antibodies, Viral
14.
Rev. argent. salud publica ; 13: 1-11, 5/02/2021.
Article in Spanish | LILACS, BINACIS, ARGMSAL | ID: biblio-1343720

ABSTRACT

INTRODUCCIÓN: Los estudios de seroprevalencia permiten monitorear la circulación del SARS-CoV-2 y dan información para evaluar medidas sanitarias. El objetivo fue conocer la proporción y evolución de la seropositividad en puntos de gran circulación de la Ciudad Autónoma de Buenos Aires (CABA) y las características clínico-epidemiológicas de los seropositivos, de abril a octubre de 2020. MÉTODOS: Se realizó un estudio descriptivo transversal de seis rondas de testeos rápidos serológicos y una encuesta de datos epidemiológicos. Se realizó un muestreo por conveniencia en tres estaciones ferroviarias cabeceras de CABA consideradas puntos de alto tránsito bidireccional del Área Metropolitana de Buenos Aires. RESULTADOS: Participaron 7339 personas. La proporción de seropositivos fue 0,6% (IC95%: 0,2-0,9) en la primera ronda y aumentó a 5,6% en la última (IC95%: 4,3-7). Al inicio aumentó la seropositividad en residentes de CABA y de la zona sur de la Región Metropolitana de Buenos Aires. El antecedente de haber presentado síntomas y el de contacto con personas con COVID-19 fueron las únicas variables relacionadas con el resultado de inmunoglobulina G positivo (p <0,05). El 56,1% (n = 97) de los seropositivos no tuvo síntomas. El 78,4% (n = 134) no fue diagnosticado en la etapa aguda. DISCUSIÓN: La seropositividad fue en ascenso en cada ronda, en coincidencia con la situación epidemiológica de la zona de residencia. Las características epidemiológicas como la proporción de seropositivos sin antecedentes de síntomas, reafirman la importancia de las medidas sanitarias poblacionales.


Subject(s)
Argentina , Epidemiologic Studies , Seroepidemiologic Studies , Coronavirus Infections , Antibodies, Viral
15.
Frontiers of Medicine ; (4): 644-648, 2021.
Article in English | WPRIM | ID: wpr-888748

ABSTRACT

The coronavirus disease 2019 (COVID-19) has caused global public health and economic crises. Thus, new therapeutic strategies and effective vaccines are urgently needed to cope with this severe pandemic. The development of a broadly neutralizing antibody against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is one of the attractive treatment strategies for COVID-19. Currently, the receptor-binding domain (RBD) of the spike (S) protein is the main target of neutralizing antibodies when SARS-CoV-2 enters human cells through an interaction between the S protein and the angiotensin-converting enzyme 2 expressed on various human cells. A single monoclonal antibody (mAb) treatment is prone to selective pressure due to increased possibility of targeted epitope mutation, leading to viral escape. In addition, the antibody-dependent enhancement effect is a potential risk of enhancing the viral infection. These risks can be reduced using multiple mAbs that target nonoverlapping epitopes. Thus, a cocktail therapy combining two or more antibodies that recognize different regions of the viral surface may be the most effective therapeutic strategy.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing , Antibodies, Viral , COVID-19 , Humans , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
16.
Chinese Journal of Biotechnology ; (12): 4066-4074, 2021.
Article in Chinese | WPRIM | ID: wpr-921487

ABSTRACT

Different fragments of SARS-CoV-2 nucleocapsid (N) protein were expressed and purified, and a fluorescence immunochromatography method for detection of SARS-CoV-2 total antibody was established. The effect of different protein fragments on the performance of the method was evaluated. The N protein sequence was analyzed by bioinformatics technology, expressed in prokaryotic cell and purified by metal ion affinity chromatography column. Different N protein fragments were prepared for comparison. EDC reaction was used to label fluorescence microsphere on the synthesized antigen to construct sandwich fluorescence chromatography antibody detection assay, and the performance was systemically evaluated. Among the 4 prepared N protein fragments, the full-length N protein (N419) was selected as the optimized coating antigen, N412 with 0.5 mol/L NaCl was used as the optimal combination; deleting 91-120 amino acids from the N-terminal of N412 reduced non-specific signal by 87.5%. the linear range of detection was 0.312-80 U/L, the limit of detection was 0.165 U/L, and the accuracy was more than 95%. A fluorescence immunochromatographic detection method for analysis of SARS-CoV-2 total antibody was established by pairing N protein fragments. The detection result achieved 98% concordance with the commercially available Guangzhou Wanfu test strip, which is expected to be used as a supplementary approach for detection of SARS-CoV-2. The assay could also provide experimental reference for improving the performance of COVID-19 antibody detection reagents.


Subject(s)
Antibodies, Viral , COVID-19 , Chromatography, Affinity , Fluorescent Antibody Technique , Humans , Microspheres , SARS-CoV-2 , Sensitivity and Specificity
17.
Chinese Journal of Biotechnology ; (12): 3221-3230, 2021.
Article in Chinese | WPRIM | ID: wpr-921419

ABSTRACT

The aim of this study was to develop a blocking enzyme-linked immunosorbent assay (bELISA) based on a biotinylated nanobody target the S1 protein of porcine epidemic diarrhea virus (PEDV) for detecting the anti-PEDV antibodies and evaluating the immune effect of the vaccine. The gene encoding the single-domain antibody sdAb3 target the PEDV S1 protein was amplified and the Avitag sequence was fused at its 3'-end. The PCR product was cloned into the expression vector pET-21b for expression and purification of the sdAb3-Avitag protein. The purified sdAb3-Avitag fusion protein was biotinylated and its activity was determined. Using the recombinant S1 protein as a coating antigen, a bELISA was established and optimized. Serum samples were tested in parallel by the bELISA and a commercial kit. The recombinant vector pET21b-sdAb3-Avitag was constructed to express the tagged sdAb3. After induction for expression, the biotin-labeled sdAb3 (sdAb3-Biotin) with high purity and good activity was obtained. For the optimized bELISA, the coating concentration of the S1 protein was 200 ng/well, the serum dilution was 1:2 and incubated for 2 h, the dilution ratio of the biotinylated sdAb3 was 1:8 000 and incubated for 30 min, the dilution of the enzyme-labeled antibody was 1:5 000 and incubated for 30 min. The bELISA had no cross reaction with the sera of major porcine viruses including transmissible gastroenteritis virus, porcine reproductive and respiratory syndrome virus and showed good specificity and reproducibility. For a total of 54 porcine serum samples tested, the overall compliance rate of the bELISA with a commercial kit was 92.56%. This study developed a rapid and reliable bELISA method, which can be used for serosurveillance and vaccine evaluation for PEDV.


Subject(s)
Animals , Antibodies, Viral , Coronavirus Infections/veterinary , Enzyme-Linked Immunosorbent Assay , Porcine epidemic diarrhea virus/genetics , Reproducibility of Results , Sensitivity and Specificity , Single-Domain Antibodies , Swine , Swine Diseases
18.
Article in English | WPRIM | ID: wpr-921355

ABSTRACT

Objective@#The coronavirus disease 2019 (COVID-19) pandemic continues to present a major challenge to public health. Vaccine development requires an understanding of the kinetics of neutralizing antibody (NAb) responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).@*Methods@#In total, 605 serum samples from 125 COVID-19 patients (from January 1 to March 14, 2020) varying in age, sex, severity of symptoms, and presence of underlying diseases were collected, and antibody titers were measured using a micro-neutralization assay with wild-type SARS-CoV-2.@*Results@#NAbs were detectable approximately 10 days post-onset (dpo) of symptoms and peaked at approximately 20 dpo. The NAb levels were slightly higher in young males and severe cases, while no significant difference was observed for the other classifications. In follow-up cases, the NAb titer had increased or stabilized in 18 cases, whereas it had decreased in 26 cases, and in one case NAbs were undetectable at the end of our observation. Although a decreasing trend in NAb titer was observed in many cases, the NAb level was generally still protective.@*Conclusion@#We demonstrated that NAb levels vary among all categories of COVID-19 patients. Long-term studies are needed to determine the longevity and protective efficiency of NAbs induced by SARS-CoV-2.


Subject(s)
Adult , Aged , Aged, 80 and over , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , Female , Humans , Kinetics , Male , Middle Aged , Neutralization Tests , SARS-CoV-2
20.
Chinese Journal of Biotechnology ; (12): 2779-2785, 2021.
Article in Chinese | WPRIM | ID: wpr-887840

ABSTRACT

To investigate whether the engineered Lactobacillus plantarum expressing the porcine epidemic diarrhea virus (PEDV) S1 gene can protect animals against PEDV, guinea pigs were fed with recombinant L. plantarum containing plasmid PVE5523-S1, with a dose of 2×10⁸ CFU/piece, three times a day, at 14 days intervals. Guinea pigs fed with wild type L. plantarum and the engineered L. plantarum containing empty plasmid pVE5523 were used as negative controls. For positive control, another group of guinea pigs were injected with live vaccine for porcine epidemic diarrhea and porcine infectious gastroenteritis (HB08+ZJ08) by intramuscular injection, with a dose of 0.2 mL/piece, three times a day, at 14 days intervals. Blood samples were collected from the hearts of the four groups of guinea pigs at 0 d, 7 d, 14 d, 24 d, 31 d, 41 d and 48 d, respectively, and serum samples were isolated for antibody detection and neutralization test analysis by enzyme-linked immunosorbent assay (ELISA). The spleens of guinea pigs were also aseptically collected to perform spleen cells proliferation assay. The results showed that the engineered bacteria could stimulate the production of secretory antibody sIgA and specific neutralizing antibody, and stimulate the increase of IL-4 and IFN-γ, as well as the proliferation of spleen cells. These results indicated that the engineered L. plantarum containing PEDV S1 induced specific immunity toward PEDV in guinea pigs, which laid a foundation for subsequent oral vaccine development.


Subject(s)
Animals , Antibodies, Viral , Coronavirus Infections/veterinary , Guinea Pigs , Lactobacillus plantarum/genetics , Porcine epidemic diarrhea virus/genetics , Swine , Swine Diseases , Viral Vaccines/genetics
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