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1.
Biomédica (Bogotá) ; 41(supl.2): 86-102, oct. 2021. graf
Article in English | LILACS | ID: biblio-1355762

ABSTRACT

Abstract | Introduction: Immunological markers have been described during COVID-19 and persist after recovery. These immune markers are associated with clinical features among SARS- CoV-2 infected individuals. Nevertheless, studies reporting a comprehensive analysis of the immune changes occurring during SARS-CoV-2 infection are still limited. Objective: To evaluate the production of proinflammatory cytokines, the antibody response, and the phenotype and function of NK cells and T cells in a Colombian family cluster with SARS-CoV-2 infection. Materials and methods: Proinflammatory cytokines were evaluated by RT-PCR and ELISA. The frequency, phenotype, and function of NK cells (cocultures with K562 cells) and T-cells (stimulated with spike/RdRp peptides) were assessed by flow cytometry. Anti-SARS-CoV-2 antibodies were determined using indirect immunofluorescence and plaque reduction neutralization assay. Results: During COVID-19, we observed a high proinflammatory-cytokine production and a reduced CD56bright-NK cell and cytotoxic response. Compared with healthy controls, infected individuals had a higher frequency of dysfunctional CD8+ T cells CD38+HLA-DR-. During the acute phase, CD8+ T cells stimulated with viral peptides exhibited a monofunctional response characterized by high IL-10 production. However, during recovery, we observed a bifunctional response characterized by the co-expression of CD107a and granzyme B or perforin. Conclusion: Although the proinflammatory response is a hallmark of SARS-CoV-2 infection, other phenotypic and functional alterations in NK cells and CD8+ T cells could be associated with the outcome of COVID-19. However, additional studies are required to understand these alterations and to guide future immunotherapy strategies.


Resumen | Introducción. Se han descrito diferentes marcadores inmunológicos durante la COVID-19, los cuales persisten incluso después de la convalecencia y se asocian con los estadios clínicos de la infección. Sin embargo, aún son pocos los estudios orientados al análisis exhaustivo de las alteraciones del sistema inmunológico en el curso de la infección. Objetivo. Evaluar la producción de citocinas proinflamatorias, la reacción de anticuerpos, y el fenotipo y la función de las células NK y los linfocitos T en una familia colombiana con infección por SARS-CoV-2. Materiales y métodos. Se evaluaron las citocinas proinflamatorias mediante RT-PCR y ELISA; la frecuencia, el fenotipo y la función de las células NK (en cocultivos con células K562) y linfocitos T CD8+ (estimulados con péptidos spike/RdRp) mediante citometría de flujo, y los anticuerpos anti-SARS-CoV-2, mediante inmunofluorescencia indirecta y prueba de neutralización por reducción de placa. Resultados. Durante la COVID-19 hubo una producción elevada de citocinas proinflamatorias, con disminución de las células NK CD56 bright y reacción citotóxica. Comparados con los controles sanos, los individuos infectados presentaron con gran frecuencia linfocitos T CD8+ disfuncionales CD38+HLA-DR-. Además, en los linfocitos T CD8+ estimulados con péptidos virales, predominó una reacción monofuncional con gran producción de IL-10 durante la fase aguda y una reacción bifuncional caracterizada por la coexpresión de CD107a y granzima B o perforina durante la convalecencia. Conclusión. Aunque la reacción inflamatoria caracteriza la infección por SARS-CoV-2, hay otras alteraciones fenotípicas y funcionales en células NK y linfocitos T CD8+ que podrían asociarse con la progresión de la infección. Se requieren estudios adicionales para entender estas alteraciones y guiar futuras estrategias de inmunoterapia.


Subject(s)
Coronavirus Infections , Killer Cells, Natural , T-Lymphocytes , Antibodies, Neutralizing , Inflammation
2.
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
3.
Buenos Aires; Comisión Nacional de Evaluación de Tecnologías de Salud; 21 abr. 2021. 14 p. (Informe de Evaluación de Tecnologías Sanitarias COVID N°02, 2).
Monography in Spanish | LILACS, BRISA, BINACIS, ARGMSAL | ID: biblio-1178379

ABSTRACT

INTRODUCIÓN: El presente informe es producto del trabajo colaborativo de la Comisión Nacional de Evaluación de Tecnologías de Salud (CONETEC), dependiente del Ministerio de Salud de la Nación y creada por RM N° 623/2018. La CONETEC realiza evaluaciones y emite recomendaciones a la autoridad sanitaria sobre la incorporación, forma de uso, financiamiento y políticas de cobertura de las tecnologías sanitarias desde una perspectiva global del sistema de salud argentino. En sus evaluaciones y recomendaciones, la CONETEC tiene en cuenta criterios de calidad, seguridad, efectividad, eficiencia y equidad, evaluados bajo dimensiones éticas, médicas, económicas y sociales. Sus resultados son consensuados mediante discusiones públicas y ponderados a través de un marco de valor explícito, con la participación de todos los actores involucrados en el proceso de toma de decisiones en salud. Los informes y recomendaciones de esta comisión surgen de este proceso público, transparente y colaborativo, siendo de libre consulta y acceso para toda la sociedad. El objetivo del presente informe es evaluar parámetros de eficacia, seguridad y conveniencia de anticuerpos policlonales equinos (suero equino hiperinmune) para el tratamiento de pacientes con COVID-19. OBJETIVO El objetivo del presente informe es evaluar parámetros de eficacia, seguridad y conveniencia de anticuerpos policlonales equinos (suero equino hiperinmune) para el tratamiento de pacientes con COVID-19. METODOLOGÍA: Realizamos una evaluación "viva" (con un proceso de actualización continua) de una tecnología sanitaria, basada en evidencia proveniente de revisiones sistemáticas "vivas" de referencia y guías de práctica clínica de alta calidad metodológica para brindar parámetros actualizados y balanceados que sean de utilidad para la toma de decisiones en los diferentes niveles de gestión. RESULTADOS: Se identificó una revisión sistemática que cumple con los criterios de inclusión del presente informe. Adicionalmente se identificaron otras dos revisiones sistemáticas con adecuado proceso de desarrollo pero ninguna contestó la pregunta pertinente al presente informe. La revisión sistemática identificada incluyó un estudio aleatorizado con un total de 243 pacientes aleatorizados a suero equino hiperinmune o placebo. Se realizaron múltiples análisis de subgrupo incluyendo uno que comparó pacientes según su severidad al comienzo del estudio. Ninguno de estos análisis mostró resultados que sugieran un efecto diferencial en los subgrupos comparados. CONCLUSIONES: El cuerpo de evidencia disponible hasta el momento muestra que existe incertidumbre en el efecto de los anticuerpos policlonales equinos (suero equino hiperinmune) sobre la mortalidad y el ingreso en ventilación mecánica. El uso de anticuerpos policlonales equinos (suero equino hiperinmune) podría impactar positivamente en el tiempo de mejoría clínica, pero podría no incrementar la proporción de pacientes que alcanzan la recuperación clínica que lleva al alta hospitalaria. Los anticuerpos policlonales equinos (suero equino hiperinmune) podrían no asociarse a afectos adversos severos. La incertidumbre sobre el efecto de la tecnología evaluada sobre los desenlaces críticos para pacientes hospitalizados con COVI-19 (mortalidad y requerimiento de ventilación invasiva) determina que la certeza en los efectos de suero equino sobre la salud de pacientes con COVID-19 sea muy baja. A pesar que la tecnología se produce en Argentina lo que facilitaría su acceso, encontramos barreras relacionadas con una amplia población objetivo y elevado costo comparativo de esta intervención que podrían acarrear problemas de producción y afectar la distribución equitativa en situaciones de alta demanda. No identificamos recomendaciones con el rigor metodológico apropiado para ser incluidas en el informe.


Subject(s)
Humans , Animals , Immunization, Passive/methods , Antibodies, Neutralizing/therapeutic use , COVID-19/drug therapy , Severity of Illness Index , Immunization, Passive/economics , Cost-Benefit Analysis , Antibodies, Neutralizing/economics , Therapeutic Index , Horses
4.
Chinese Journal of Epidemiology ; (12): 1750-1756, 2021.
Article in Chinese | WPRIM | ID: wpr-922724

ABSTRACT

Domestic and foreign literatures related to the persistence of SARS-CoV-2 and the re-positive cases infected with SARS-CoV-2 were reviewed, and the characteristics and infectivity of the re-positive cases were analyzed to provide scientific evidence for the improvement of case management and the development of measures to stop the spread of SARS-CoV-2. Existing studies have shown that re-positive rate of SARS-CoV-2 ranged from 2.4% to 19.8%, the median of interval between re-positive detection and discharge was 4-15 days. Following the second course of the disease, the anti-SARS-CoV-2 IgM, IgG and IgA positive rates of the cases were 11.11%-86.08%, 52.00%-100.00% and 61.54%-100.00% respectively, the total antibody and neutralizing antibody positive rates were 98.72% and 88.46%. The viral load of the re-positive cases was lower than that in the initial infection. At least 3 380 re-positive cases have been reported globally. SARS-CoV-2 strains were isolated from the samples of 3 re-positive cases (1 immunodeficiency case and 2 cases with abnormal pulmonary imaging). There were close contacts that were infected by an asymptomatic case taking immunosuppressive agents. In conclusion, the infectivity of re-positive cases infected with SARS-CoV-2 is generally very low. Rare re-positive cases infected with SARS-CoV-2 might cause further transmission. The management approach for the re-positive cases can be based on the assessment of the individual transmission risk according to the pathogen detection results.


Subject(s)
Antibodies, Neutralizing , Antibodies, Viral , COVID-19 , Humans , Immunoglobulin M , SARS-CoV-2
5.
Chinese Journal of Biotechnology ; (12): 3211-3220, 2021.
Article in Chinese | WPRIM | ID: wpr-921418

ABSTRACT

To develop Senecavirus A (SVA) virus-like particles (VLPs), a recombinant prokaryotic expression plasmid pET28a-SVA-VP031 was constructed to co-express SVA structural proteins VP0, VP3 and VP1, according to the genomic sequence of the field isolate CH-FJ-2017 after the recombinant proteins were expressed in E .coli system, and purified by Ni+ ion chromatographic method. The SVA VLPs self-assemble with a high yield in vitro buffer. A typical VLPs with an average diameter of 25-30 nm which is similar to native virions by using TEM detection. Animals immunized by SVA VLPs shown that the VLPs induced high titers neutralizing antibodies in Guinea pigs. This study indicated that the VLPs produced with co-expressing SVA structural proteins VP0, VP3 and VP1 in prokaryotic system is a promising candidate and laid an important foundation for the development of a novel SVA VLPs vaccine.


Subject(s)
Animals , Antibodies, Neutralizing , Escherichia coli/genetics , Genomics , Guinea Pigs , Picornaviridae/genetics
6.
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
7.
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
8.
Protein & Cell ; (12): 717-733, 2021.
Article in English | WPRIM | ID: wpr-888715

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic is caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is spread primary via respiratory droplets and infects the lungs. Currently widely used cell lines and animals are unable to accurately mimic human physiological conditions because of the abnormal status of cell lines (transformed or cancer cells) and species differences between animals and humans. Organoids are stem cell-derived self-organized three-dimensional culture in vitro and model the physiological conditions of natural organs. Here we showed that SARS-CoV-2 infected and extensively replicated in human embryonic stem cells (hESCs)-derived lung organoids, including airway and alveolar organoids which covered the complete infection and spread route for SARS-CoV-2 within lungs. The infected cells were ciliated, club, and alveolar type 2 (AT2) cells, which were sequentially located from the proximal to the distal airway and terminal alveoli, respectively. Additionally, RNA-seq revealed early cell response to virus infection including an unexpected downregulation of the metabolic processes, especially lipid metabolism, in addition to the well-known upregulation of immune response. Further, Remdesivir and a human neutralizing antibody potently inhibited SARS-CoV-2 replication in lung organoids. Therefore, human lung organoids can serve as a pathophysiological model to investigate the underlying mechanism of SARS-CoV-2 infection and to discover and test therapeutic drugs for COVID-19.


Subject(s)
Adenosine Monophosphate/therapeutic use , Alanine/therapeutic use , Alveolar Epithelial Cells/virology , Antibodies, Neutralizing/therapeutic use , COVID-19/virology , Down-Regulation , Drug Discovery , Human Embryonic Stem Cells/metabolism , Humans , Immunity , Lipid Metabolism , Lung/virology , RNA, Viral/metabolism , SARS-CoV-2/physiology , Virus Replication/drug effects
9.
J. venom. anim. toxins incl. trop. dis ; 27: e20210028, 2021. tab, mapas, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1351018

ABSTRACT

Venom from Amazonian scorpions of the genus Tityus contains components capable of eliciting a distinct clinical, mostly neurological, syndrome. This contrasts with the mainly autonomic manifestations produced after envenomation by congeneric southern and northern South American species. Herein, we summarize Pan-Amazonian scorpionism by synthesizing available toxinological, clinical, and molecular data gathered from all affected areas in Amazonia, including Brazil, Ecuador, Colombia, Peru, Venezuela, and French Guiana. We searched multiple databases, as well as our own records, for reports of scorpion envenomations in Amazonia by confirmed Tityus spp., and compared the clinical manifestations. To help uncover clinical and venom relationships among problematic species, we explored phylogenetic relationships with a rate-calibrated analysis of mitochondrial COI data from available species. The possible existence of diversity gradients for venom toxic and immunogenic components despite the predicted strong phylogenetic association among species is underscored by discussed clinical and toxinological findings. A multicentric effort, involving all nations affected by this neglected disease, is urgently needed to offer alternatives for treating and understanding this pathology, including the preparation of neutralizing antibodies with a broad range of efficacy.(AU)


Subject(s)
Animals , Phylogeny , Scorpions , Toxicology , Antibodies, Neutralizing
10.
Goiânia; s.n; 08 set. 2020. 1-5 p.
Non-conventional in Portuguese | ColecionaSUS, LILACS, ColecionaSUS, CONASS, SES-GO | ID: biblio-1247459

ABSTRACT

Com referencial teórico do ano de 2020, foram condensadas as evidências sobre o uso de plasma convalescente no tratamento da Covid-19, abordando um estudo de uma série de casos de cinco pacientes com diagnóstico de COVID-19 e síndrome do desconforto respiratório; um estudo piloto, 10 pacientes com diagnostico de COVID-19 confirmado por RT-PCR; um estudo (preprint) envolvendo 5.000 pacientes; um ensaio clínico aberto, multicêntrico incluindo 103 pacientes com quadro grave de COVID-19; uma atualização de Revisão da Cochrane, que incluiu 20 estudos, 5443 participantes (5211 receberam tratamento com plasma). Resumem as Diretrizes de Food and Drug Administration (FDA), dos Estados Unidos para utilização da terapia. No Brasil, pontua as recomendações da ANVISA, as considerações do Ministério da Saúde e os esclarecimentos do Ofício Circular nº 40/2020. Os estudos analisados pontuam resultados positivos quanto à eficácia e segurança e apontam necessidade de maiores evidências


With the theoretical framework of the year 2020, the evidence on the use of convalescent plasma in the treatment of Covid-19 was condensed, addressing a study of a case series of five patients diagnosed with COVID-19 and respiratory distress syndrome; a pilot study, 10 patients with a diagnosis of COVID-19 confirmed by RT-PCR; a study (preprint) involving 5,000 patients; an open, multicenter clinical trial including 103 patients with severe COVID-19; a Cochrane Review update, which included 20 studies, 5443 participants (5211 received plasma treatment). They summarize the US Food and Drug Administration (FDA) Guidelines for using the therapy. In Brazil, the recommendations of ANVISA, the considerations of the Ministry of Health and the clarifications of Circular Letter nº 40/2020 are punctuated. The analyzed studies show positive results regarding efficacy and safety and point to the need for more evidence


Subject(s)
Humans , Plasma , Pneumonia, Viral/therapy , Coronavirus Infections/therapy , Antibodies, Neutralizing/therapeutic use , Complementary Therapies/adverse effects
11.
Brasília; s.n; 11 ago. 2020.
Non-conventional in Portuguese | PIE, LILACS, BRISA, PIE | ID: biblio-1117979

ABSTRACT

O Informe Diário de Evidências é uma produção do Ministério da Saúde que tem como objetivo acompanhar diariamente as publicações científicas sobre tratamento farmacológico e vacinas para a COVID-19. Dessa forma, são realizadas buscas estruturadas em bases de dados biomédicas, referentes ao dia anterior desse informe. Não são incluídos estudos pré-clínicos (in vitro, in vivo, in silico). A frequência dos estudos é demonstrada de acordo com a sua classificação metodológica (revisões sistemáticas, ensaios clínicos randomizados, coortes, entre outros). Para cada estudo é apresentado um resumo com avaliação da qualidade metodológica. Essa avaliação tem por finalidade identificar o grau de certeza/confiança ou o risco de viés de cada estudo. Para tal, são utilizadas ferramentas já validadas e consagradas na literatura científica, na área de saúde baseada em evidências. Cabe ressaltar que o documento tem caráter informativo e não representa uma recomendação oficial do Ministério da Saúde sobre a temática. Foram encontrados 14 artigos e 5 protocolos.


Subject(s)
Humans , Pneumonia, Viral/drug therapy , Coronavirus Infections/drug therapy , Betacoronavirus/drug effects , Ribavirin/therapeutic use , Technology Assessment, Biomedical , Ursodeoxycholic Acid/therapeutic use , Immunoglobulins/therapeutic use , Prednisolone/therapeutic use , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Chloroquine/therapeutic use , Cross-Sectional Studies , Cohort Studies , Interferon-alpha/therapeutic use , Tacrolimus/therapeutic use , Adrenal Cortex Hormones/therapeutic use , Azithromycin/therapeutic use , Ritonavir/therapeutic use , Antibodies, Neutralizing/therapeutic use , Mesenchymal Stem Cells , Lopinavir/therapeutic use , Folic Acid/therapeutic use , Meropenem/therapeutic use , Hydroxychloroquine/therapeutic use , Antibodies, Monoclonal/therapeutic use , Mycophenolic Acid/therapeutic use
12.
Frontiers of Medicine ; (4): 746-751, 2020.
Article in English | WPRIM | ID: wpr-880959

ABSTRACT

The ongoing pandemic of Coronavirus disease 19 (COVID-19) is caused by a newly discovered β Coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). How long the adaptive immunity triggered by SARS-CoV-2 can last is of critical clinical relevance in assessing the probability of second infection and efficacy of vaccination. Here we examined, using ELISA, the IgG antibodies in serum specimens collected from 17 COVID-19 patients at 6-7 months after diagnosis and the results were compared to those from cases investigated 2 weeks to 2 months post-infection. All samples were positive for IgGs against the S- and N-proteins of SARS-CoV-2. Notably, 14 samples available at 6-7 months post-infection all showed significant neutralizing activities in a pseudovirus assay, with no difference in blocking the cell-entry of the 614D and 614G variants of SARS-CoV-2. Furthermore, in 10 blood samples from cases at 6-7 months post-infection used for memory T-cell tests, we found that interferon γ-producing CD4


Subject(s)
Adaptive Immunity/physiology , Adult , Aged , Antibodies, Neutralizing/blood , COVID-19/immunology , Cohort Studies , Female , Humans , Immunoglobulin G/blood , Male , Middle Aged , SARS-CoV-2/immunology , T-Lymphocytes/physiology , Time Factors , Viral Proteins/immunology
13.
Article in English | WPRIM | ID: wpr-880737

ABSTRACT

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which first affected humans in China on December 31, 2019 (Shi et al., 2020). Coronaviruses generally cause mild, self-limiting upper respiratory tract infections in humans, such as the common cold, pneumonia, and gastroenteritis (To et al., 2013; Berry et al., 2015; Chan et al., 2015). According to the Report of the World Health Organization (WHO)-China Joint Mission on COVID-19 (WHO, 2020), the case fatality rate of COVID-19 increases with age, while the rate among males is higher than that among females (4.7% and 2.8%, respectively). Since an effective vaccine and specific anti-viral drugs are still under development, passive immunization using the convalescent plasma (CP) of recovered COVID-19 donors may offer a suitable therapeutic strategy for severely ill patients in the meantime. So far, several studies have shown therapeutic efficacy of CP transfusion in treating COVID-19 cases. A pilot study first reported that transfusion of CP with neutralizing antibody titers above 1:640 was well tolerated and could potentially improve clinical outcomes through neutralizing viremia in severe COVID-19 cases (Chen et al., 2020). Immunoglobulin G (IgG) and IgM are the most abundant and important antibodies in protecting the human body from viral attack (Arabi et al., 2015; Marano et al., 2016). Our study aimed to understand the aspects of plasma antibody titer levels in convalescent patients, as well as assessing the clinical characteristics of normal, severely ill, and critically ill patients, and thus provide a basis for guiding CP therapy. We also hoped to find indicators which could serve as a reference in predicting the progression of the disease.


Subject(s)
Adult , Aged , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/therapy , China , Female , Humans , Immunization, Passive , Immunoglobulin G/blood , Immunoglobulin M/blood , Male , Middle Aged
14.
Article in English | WPRIM | ID: wpr-811062

ABSTRACT

PURPOSE: Th17-associated inflammation is increased in chronic rhinosinusitis with nasal polyp (CRSwNP), and is associated with disease severity and steroid resistance. Overexpressed interleukin (IL)-17A affects CRSwNP by tissue remodeling, eosinophilic accumulation, and neutrophilic infiltration. We aimed to identify the role of IL-17A in CRSwNP and to evaluate the effects of anti-IL-17A blocking antibody on nasal polyp (NP) formation using a murine NP model. Moreover, we sought to investigate whether the inhibition of mechanistic target of the rapamycin (mTOR) signal pathway could suppress IL-17A expression and NP formation.METHODS: Human sinonasal tissues from control subjects and patients with chronic rhinosinusitis (CRS) were analyzed using immunohistochemistry (IHC) and immunofluorescence staining. The effects of IL-17A neutralizing antibody and rapamycin were evaluated in a murine NP model. Mouse samples were analyzed using IHC, quantitative real-time polymerase chain reaction, and enzyme-linked immunosorbent assay.RESULTS: IL-17A+ inflammatory cells were significantly increased in number in NP from patients with CRSwNP compared to that in uncinate process tissues from control subjects and patients with CRS without NP or CRSwNP. CD68+ M1 macrophages dominantly expressed IL-17A, followed by neutrophils and T helper cells, in NP tissues. Neutralization of IL-17A effectively reduced the number of NPs, inflammatory cytokines, and IL-17A-producing cells, including M1 macrophages. Inhibition of IL-17A via the mTOR pathway using rapamycin also attenuated NP formation and inflammation in the murine NP model.CONCLUSIONS: IL-17A possibly plays a role in the pathogenesis of CRSwNP, the major cellular source being M1 macrophage in NP tissues. Targeting IL-17A directly or indirectly may be an effective therapeutic strategy for CRSwNP.


Subject(s)
Animals , Antibodies, Neutralizing , Cytokines , Enzyme-Linked Immunosorbent Assay , Eosinophils , Fluorescent Antibody Technique , Humans , Immunohistochemistry , Inflammation , Interleukin-17 , Interleukins , Macrophages , Mice , Nasal Polyps , Neutrophils , Real-Time Polymerase Chain Reaction , Signal Transduction , Sinusitis , Sirolimus , T-Lymphocytes, Helper-Inducer
17.
Medicina (B.Aires) ; 79(6): 493-501, dic. 2019. ilus, tab
Article in Spanish | LILACS | ID: biblio-1056758

ABSTRACT

En los ó;ºltimos aó;±os la terapia gó;©nica se ha posicionado como una opció;n real y segura en el desarrollo de alternativas terapó;©uticas para la cura y la prevenció;n de diferentes enfermedades. Consiste en la inserció;n de material genó;©tico en un tejido o có;©lula defectuosa, mediante el uso de un vector. Existen varias consideraciones para seleccionar el vector más apropiado, incluyendo el potencial de unió;n y entrada a la có;©lula diana, la capacidad de transferencia del material genó;©tico al nó;ºcleo, la habilidad de expresió;n del inserto y la ausencia de toxicidad. En el panorama actual, los vectores virales más utilizados son los derivados de los virus adenoasociados (AAV). Características como su bioseguridad, baja toxicidad y tropismo selectivo, han posibilitado su evaluació;n como opció;n terapó;©utica en un amplio nó;ºmero de enfermedades monogó;©nicas o complejas. A pesar de sus ventajas, los vectores AAV presentan inconvenientes, siendo el más importante la respuesta inmune del paciente al vector, especialmente la respuesta mediada por anticuerpos neutralizantes (NAb). Los NAb disminuyen la transducció;n del vector e impiden la expresió;n del gen que transporta, limitando su aplicació;n clínica. Por lo tanto, identificar y cuantificar la presencia y actividad de los NAbs, es el primer paso en cualquier protocolo de terapia gó;©nica con vectores AAV. La presencia de NAb depende principalmente de la exposició;n al virus en la naturaleza y varía drásticamente segó;ºn edad, localizació;n geográfica y estado de salud de la persona evaluada.


In recent years, gene therapy has been positioned as a real and safe option in the development of therapeutic alternatives for the cure and prevention of different diseases. It consists in the insertion of genetic material in a defective tissue or cell, through the use of a vector. There are several considerations for selecting the most appropriate vector, including the potential for binding and entry to the target cell, the ability of the genetic material to transfer to the nucleus, the ability to express the insert, and the absence of toxicity. In the current scenario, the most commonly used viral vectors are those derived from adeno-associated viruses (AAV). Characteristics such as biosafety, low toxicity and selective tropism have enabled its evaluation as a therapeutic option in many monogenic or complex diseases. Despite their advantages, AAV vectors have drawbacks, the most important being the patient’s immune response to the vector, especially the response mediated by neutralizing antibodies (NAb). NAbs decrease the transduction of the vector and prevent the expression of the gene it transports, limiting its clinical application. Therefore, identifying and quantifying the presence and activity of NAbs is the first step in any gene therapy protocol with AAV vectors. The presence of NAbs depends mainly on exposure to the virus in nature and varies drastically according to age, geographic location and health status of the person evaluated.


Subject(s)
Humans , Male , Female , Genetic Therapy/methods , Dependovirus/genetics , Dependovirus/immunology , Parvoviridae Infections/genetics , Parvoviridae Infections/immunology , Parvoviridae Infections/virology , Antibodies, Neutralizing/analysis , Serogroup , Genetic Vectors , Antibodies, Viral/analysis
18.
J. bras. nefrol ; 41(1): 145-151, Jan.-Mar. 2019. tab, graf
Article in English | LILACS | ID: biblio-1002413

ABSTRACT

ABSTRACT Introduction: Anemia is a frequent multifactorial complication of CKD seen in patients on dialysis derived mainly from impaired erythropoietin (EPO) production. A less common cause of anemia in individuals with CKD is pure red cell aplasia (PRCA) secondary to the production of anti-EPO antibodies. Objective: This paper aimed two describe two cases of PRCA secondary to the production of anti-EPO antibodies including choice of treatment, patient progression, and a literature review. Materials: This study included the cases of two patients with CKD on hemodialysis with severe anemia in need of specific investigation and management. Results: Patient 1 with CKD secondary to hypertension treated with EPO for 7 months showed persistent decreases in hemoglobin (Hb) levels despite the subcutaneous administration of increasing doses of EPO; the patient required recurring blood transfusions. Workup and imaging tests were negative for the main causes of anemia in individuals with CKD on dialysis. Patient 2 with CKD secondary to adult polycystic kidney disease had been taking EPO for 2 years. The patient developed severe abrupt anemia the month he was started on HD, and required recurring transfusions to treat the symptoms of anemia. Workup and imaging findings were inconclusive. Specific laboratory tests confirmed the patients had anti-EPO antibodies. After six months of immunosuppressant therapy (corticosteroids + cyclosporine) the patients were stable with Hb > 9.0 g/dl. Conclusion: PRCA is a rare condition among patients on dialysis treated with rhEPO and should be considered as a possible cause of refractory anemia. Treating patients with PRCA may be challenging, since the specific management and diagnostic procedures needed in this condition are not always readily available.


RESUMO Introdução: Anemia é complicação frequente da Doença Renal Crônica (DRC) em pacientes dialíticos. Apresenta caráter multifatorial principalmente pela insuficiente produção de eritropoietina (EPO). Situação rara causadora de anemia na DRC é Aplasia Pura de Células Vermelhas (APCV), em decorrência da produção de anticorpos anti-EPO. Objetivo: Descrever 2 casos de APCV com formação de anticorpos anti-EPO, sua abordagem clínica, evolução e revisão de literatura. Métodos: Dois pacientes em hemodiálise que desenvolveram anemia grave, necessitando investigação e manejo específico. Resultados: Paciente nº 1: feminina, 75 anos, DRC secundária à hipertensão arterial. Após 7 meses com EPO desenvolveu queda persistente em valores de hemoglobina (Hb) mesmo com incremento em doses EPO SC, necessitando transfusões de sangue recorrentes. Extensa investigação laboratorial e de imagem resultou negativa para principais causas de anemia. Paciente nº 2: masculino, 66 anos, DRC secundária à DRPA, há 2 anos em uso de EPO. No mês de entrada em HD desenvolveu anemia severa, também exigindo transfusões recorrentes para tratamento da anemia sintomática. Extensa investigação laboratorial e por imagem, sem chegar a uma conclusão definitiva. Em ambos os casos a presença de anticorpos anti-EPO foi confirmada por exames laboratoriais específicos. Terapia imunossupressora resultou em estabilização do quadro e Hb > 9,0 g/dl em ambos os pacientes, 6 meses após início do tratamento. Conclusão: APCV é condição rara entre pacientes dialíticos que recebem EPOHuR e deve ser lembrada como causa de anemia refratária. Seu manejo específico e diagnóstico laboratorial nem sempre acessível, tornando desafiadora a condução dos casos para o nefrologista.


Subject(s)
Humans , Male , Female , Aged , Recombinant Proteins/therapeutic use , Erythropoietin/immunology , Erythropoietin/therapeutic use , Renal Dialysis/adverse effects , Red-Cell Aplasia, Pure/etiology , Antibodies, Neutralizing/blood , Kidney Failure, Chronic/drug therapy , Recombinant Proteins/adverse effects , Prednisone/administration & dosage , Prednisone/therapeutic use , Erythropoietin/biosynthesis , Erythropoietin/adverse effects , Kidney Transplantation , Treatment Outcome , Cyclosporine/administration & dosage , Cyclosporine/therapeutic use , Red-Cell Aplasia, Pure/drug therapy , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/therapeutic use , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/therapeutic use
19.
Ghana Med. J. (Online) ; 53(2): 170-180, 2019. ilus
Article in English | AIM, AIM | ID: biblio-1262301

ABSTRACT

Introduction: Ghana was declared polio-free in 2015 after the last polio case in 2008. We determined the poliovirus neutralizing antibody levels among individuals to identify possible immunity gaps. Methods: A cross-sectional, hospital-based study was undertaken in Northern, Ashanti and Greater Accra regions of Ghana. Individuals referred for haematology at the teaching hospitals' laboratories were invited to participate in our study. Neutralizing-antibody titers to poliovirus serotypes 1,2 & 3 were assayed by WHO-standards. Antibody titers of ≥8 were considered protective. Bivariate and multivariate analyses were conducted on subject characteristics to assess potential factors for failure to seroconvert. P-values < 0.05 were considered statistically significant. Results: Poliovirus (PV) neutralizing-antibody serotypes 1, 2 and 3 were detected in 86.0% (264/307), 84% (258/307) and 75% (230/307) of samples respectively. 60.1% (185/307) were seropositive for the three poliovirus serotypes. Neutralizing poliovirus antibodies for PV1 and PV2 were higher than for PV3. Seroprevalence of poliovirus-neutralizing antibodies among males (PV1=51.9%, PV2= 51.6% and PV3= 52.6%) were higher than in females. Seroprevalence rates of poliovirus-neutralizing antibodies (PV1, PV2, and PV3) were highest in the Northern region (90%, 81%, and 77%). Poliovirus neutralizing-antibodies (PV1and PV2) decreased with age [p< 0.001]. Low seroprevalence of poliovirus-neutralizing antibodies was significantly associated with low school attendance of mothers (p<0.001). Conclusion: Our study population has some protection from polio. However, immunity appears to be lower with a higher age or low Mother's education. This may suggest the need for young-adult booster-dose to minimize the risk of wild poliovirus infection


Subject(s)
Antibodies, Neutralizing , Poliomyelitis , Poliovirus/immunology
20.
Article in English | WPRIM | ID: wpr-758963

ABSTRACT

The Schmallenberg virus (SBV) is an orthobunyavirus that causes abortions, stillbirths, and congenital defects in pregnant sheep and cattle. Inactivated or live attenuated vaccines have been developed in endemic countries, but there is still interest in the development of SBV vaccines that would allow Differentiating Infected from Vaccinated Animals (DIVA). Therefore, an attempt was made to develop novel DIVA-compatible SBV vaccines using SBV glycoproteins expressed in baculovirus. All vaccines and phosphate buffered saline (PBS) controls were prepared with adjuvant and administered subcutaneously to cattle at 6 month of age. The first trial included 2 groups of animals vaccinated with either carboxyl-terminus glycoprotein (Gc) or PBS and boosted after 2 weeks. In the second trial, 3 groups of cattle were administered either Gc, Gc and amino-terminus glycoprotein (Gn), or PBS with a booster vaccination after 3 weeks. The animals were challenged with SBV 9 days after the booster vaccination in the first study, and 3 weeks after the booster vaccination in the second study. Using a SBV Gc-specific enzyme-linked immunosorbent assay, antibodies were first detected in serum samples 14 days after the first vaccination in both trials, and peaked on days 7 and 9 after the booster in the first and second trials, respectively. Low titers of neutralizing antibodies were detected in serum from only 3/6 and 2/4 animals in the first and second trial, respectively, at 14 days after the first vaccination. The titers increased 2 to 3-fold after the booster vaccination. SBV-specific RNA was detected in the serum and selective tissues in all animals after SBV challenge independent of vaccination status. The SBV candidate vaccines neither prevented viremia nor conferred protection against SBV infection.


Subject(s)
Animals , Antibodies , Antibodies, Neutralizing , Baculoviridae , Cattle , Congenital Abnormalities , Enzyme-Linked Immunosorbent Assay , Glycoproteins , Orthobunyavirus , RNA , Sheep , Stillbirth , Vaccination , Vaccines , Vaccines, Attenuated , Vaccines, Subunit , Viremia
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