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1.
Sci Rep ; 14(1): 20930, 2024 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251702

RESUMEN

SARS-CoV-2 caused the pandemic situation experienced since the beginning of 2020, and many countries faced the rapid spread and severe form of the disease. Mechanisms of interaction between the virus and the host were observed during acute phase, but few data are available when related to immunity dynamics in convalescents. We conducted a longitudinal study, with 51 healthy donors and 62 COVID-19 convalescent patients, which these had a 2-month follow-up after symptoms recovery. Venous blood sample was obtained from all participants to measure blood count, subpopulations of monocytes, lymphocytes, natural killer cells and dendritic cells. Serum was used to measure cytokines, chemokines, growth factors, anti-N IgG and anti-S IgG/IgM antibodies. Statistic was performed by Kruskal-Wallis test, and linear regression with days post symptoms and antibody titers. All analysis had confidence interval of 95%. Less than 35% of convalescents were anti-S IgM+, while more than 80% were IgG+ in D30. Anti-N IgG decreased along time, with loss of seroreactivity of 13%. Eosinophil count played a distinct role on both antibodies during all study, and the convalescence was orchestrated by higher neutrophil-to-lymphocyte ratio and IL-15, but initial stages were marked by increase in myeloid DCs, B1 lymphocytes, inflammatory and patrolling monocytes, G-CSF and IL-2. Later convalescence seemed to change to cytotoxicity mediated by T lymphocytes, plasmacytoid DCs, VEGF, IL-9 and CXCL10. Anti-S IgG antibodies showed the longest perseverance and may be a better option for diagnosis. The inflammatory pattern is yet present on initial stage of convalescence, but quickly shifts to a reparative dynamic. Meanwhile eosinophils seem to play a role on anti-N levels in convalescence, although may not be the major causative agent. We must highlight the importance of immunological markers on acute clinical outcomes, but their comprehension to potentialize adaptive system must be explored to improve immunizations and further preventive policies.


Asunto(s)
Anticuerpos Antivirales , COVID-19 , Convalecencia , Citocinas , Inmunoglobulina G , SARS-CoV-2 , Humanos , COVID-19/inmunología , COVID-19/sangre , Masculino , Femenino , Adulto , Persona de Mediana Edad , SARS-CoV-2/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Citocinas/sangre , Inmunoglobulina M/sangre , Inmunoglobulina M/inmunología , Estudios Longitudinales , Anciano , Eosinófilos/inmunología , Eosinófilos/metabolismo
2.
J Med Virol ; 96(2): e29443, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38373154

RESUMEN

Cross-neutralizing activity of human antibody response against Dengue virus complex (DENV) changes importantly over time. Domain III (DIII) of the envelope protein of DENV elicits a potently neutralizing and mostly type-specific IgG response. We used sera from 24 individuals from early- or late convalescence of DENV1 infection to investigate the evolution of anti-DIII human IgG with the time lapse since the infection. We evaluated the correlation between the serotype-specific reactivity against recombinant DIII proteins and the neutralization capacity against the four serotypes, and examined its behavior with the time of convalescence. Also, we use a library of 71 alanine mutants of surface-exposed amino acid residues to investigate the dominant epitopes. In early convalescence anti-DIII titers and potency of virus neutralization were positively associated with correlation coefficients from 0.82 to 1.0 for the four serotypes. For late convalescence, a positive correlation (r = 0.69) was found only for DENV1. The dominant epitope of the type-specific response is centered in the FG-loop (G383, E384, and K385) and includes most of the lateral ridge. The dominant epitope of the anti-DIII cross-reactive IgG in secondary infections shifts from the A-strand during early convalescence to a site centered in residues E314-H317 of the AB-loop and I352-E368 of the DI/DIII interface, in late convalescence. An immunoassay based on the detection of IgG anti-DIII response can be implemented for detection of infecting serotype in diagnosis of DENV infection, either primary or secondary. Human dominant epitopes of the cross-reactive circulating antibodies change with time of convalescence.


Asunto(s)
Virus del Dengue , Dengue , Humanos , Epítopos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Formación de Anticuerpos , Convalecencia , Proteínas del Envoltorio Viral , Proteínas Recombinantes/metabolismo , Inmunoglobulina G/metabolismo , Reacciones Cruzadas
3.
Virology ; 587: 109883, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37757730

RESUMEN

The Dengue virus complex (DENV), formed by four serotypes, constitutes the most important arbovirus affecting humans. The structural domain III of their envelope protein (DIII) elicits strongly neutralizing serotype-specific antibodies. Contrasting results have been obtained regarding their role in the serum neutralizing activity of infected patients. We used a DENV immune serum from a secondary infection to examine the impact of characterizing the anti-DIII antibody response after affinity purification with recombinant DIII proteins to eliminate potential interferences from the interactions with human plasma proteins and other anti-DENV antibodies. Total anti-DENV IgG repertoire and anti-DIIIE antibodies were compared in functionality. In early convalescence, reactivity of anti-DIII antibodies is serotype specific and exhibits the strongest reactivity with infecting serotypes. Purification of anti-DIII antibodies emphasizes the reactivity profile as compared to total IgG fraction and serum. Serotype-specificity of the virus neutralization activity correlated with the apparent kD of the binding to recombinant DIIIs.


Asunto(s)
Virus del Dengue , Dengue , Humanos , Virus del Dengue/genética , Anticuerpos Antivirales , Convalecencia , Anticuerpos Neutralizantes , Inmunoglobulina G/metabolismo , Proteínas del Envoltorio Viral/química
4.
Pediatr Infect Dis J ; 42(9): 792-800, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37463399

RESUMEN

BACKGROUND: Pediatric dengue and sepsis share clinical and pathophysiologic aspects. Multiple inflammatory and regulatory cytokines, decoy receptors and vascular permeability factors have been implicated in the pathogenesis of both diseases. The differential pattern and dynamic of these soluble factors, and the relationship with clinical severity between pediatric dengue and sepsis could offer new diagnosis and therapeutic strategies. METHODS: We evaluated the concentration levels of 11 soluble factors with proinflammatory, regulatory and vascular permeability involvement, in plasma from children with dengue or sepsis, both clinically ranging from mild to severe, in the early, late and convalescence phases of the disease. RESULTS: During early acute infection, children with sepsis exhibited specific higher concentration levels of IL-6, vascular endothelial growth factor (VEGF), and its soluble decoy receptor II (sVEGFR2) and lower concentration levels of IL-10 and the soluble tumor necrosis factor receptor 2 (sTNFR2), in comparison with children with severe dengue. In addition, the circulating amounts of soluble ST2, and VEGF/sVEGFR2 were widely associated with clinical and laboratory indicators of dengue severity, whereas secondary dengue virus infections were characterized by an enhanced cytokine response, relative to primary infections. In severe forms of dengue, or sepsis, the kinetics and the cytokines response during the late and convalescence phases of the disease also differentiate. CONCLUSIONS: Dengue virus infection and septic processes in children are characterized by cytokine responses of a specific magnitude, pattern and kinetics, which are implicated in the pathophysiology and clinical outcome of these diseases.


Asunto(s)
Dengue , Sepsis , Dengue Grave , Humanos , Niño , Dengue Grave/diagnóstico , Dengue Grave/complicaciones , Factor A de Crecimiento Endotelial Vascular , Dengue/diagnóstico , Dengue/complicaciones , Convalecencia , Citocinas , Sepsis/diagnóstico , Sepsis/complicaciones , Biomarcadores
5.
Hematol Oncol Stem Cell Ther ; 16(2): 124-132, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-34450106

RESUMEN

OBJECTIVE/BACKGROUND: Sickle cell anemia (SCA) is associated with increased levels of extracellular heme, which is a key mediator of inflammation in this condition. Despite abundant evidence supporting this concept in cell and animal models, few studies addressed the association between heme levels and the development and severity of acute vasoocclusive crises (VOC) in humans. METHODS: A cross-sectional study was conducted in patients with acute VOC. Total extracellular heme levels were measured in both plasma and serum at admission and after convalescence, and correlated with other clinical and laboratory markers of SCA severity. RESULTS: A total of 28 episodes of VOC in 25 patients were included. Heme levels were similar between admission and convalescence, and correlated with the difference between pre and post hemoglobin, and SCA severity estimated by a composite score of clinical and laboratory markers. Heme levels were neither associated with VOC severity nor with markers of hemostasis activation, and were similar to those reported in an independent population of SCA patients at steady state. DISCUSSION: Acute VOC are not characterized by significant increases in total extracellular heme levels. Studies measuring the fraction of free extracellular heme unbound to proteins are warranted to further refine our understanding of the role of heme in acute VOC.


Asunto(s)
Anemia de Células Falciformes , Compuestos Orgánicos Volátiles , Humanos , Hemo , Estudios Transversales , Convalecencia , Anemia de Células Falciformes/complicaciones , Biomarcadores
6.
Int J Neurosci ; 133(6): 672-675, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34370958

RESUMEN

Background and aim: With an ever-increasing population of patients recovering form severe coronavirus disease 2019 (COVID-19), recognizing long-standing and delayed neurologic manifestations is crucial. Here, we present a patient developing posterior reversible encephalopathy syndrome (PRES) in the convalescence form severe coronavirus disease 2019 (COVID-19).Case presentation: A 61-year-old woman with severe (COVID-19) confirmed by nasopharyngeal real-time reverse transcription-polymerase chain reaction (RT-PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) required invasive mechanical ventilation 24-hours after admission. During her intensive care unit stay, she developed transient acute kidney injury and septic shock. She was extubated after 22 days. On day 25, she developed generalized tonic-clonic seizures. Magnetic resonance imaging (MRI) of the brain showed bilateral subcortical lesions on the parietal and occipital lobes and multiple micro-and macro-bleeds, consistent with PRES. At this point, RT-PCR for SARS-CoV-2 in a respiratory specimen and cerebrospinal fluid was negative. She was discharged home 35 days after admission on oral levetiracetam. Control MRI five months after discharge showed bilateral focal gliosis. On follow-up, she remains seizure-free on levetiracetam.Conclusions: PRES has been observed before as a neurological manifestation of acute COVID-19; to our knowledge, this is the first PRES case occurring in a hospitalized patient already recovered from COVID-19. A persistent proinflammatory/prothrombotic state triggered by SARS-CoV-2 infection may lead to long-standing endothelial dysfunction, resulting in delayed PRES in patients recovering from COVID-19. With a rapid and exponential increase in survivors of acute COVID-19, clinicians should be aware of delayed (post-acute) neurological damage, including PRES.


Asunto(s)
COVID-19 , Síndrome de Leucoencefalopatía Posterior , Humanos , Femenino , Persona de Mediana Edad , COVID-19/complicaciones , SARS-CoV-2 , Síndrome de Leucoencefalopatía Posterior/diagnóstico por imagen , Síndrome de Leucoencefalopatía Posterior/etiología , Síndrome de Leucoencefalopatía Posterior/patología , Convalecencia , Levetiracetam
7.
EBioMedicine ; 78: 103972, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35366624

RESUMEN

BACKGROUND: A major challenge of the SARS-CoV-2 pandemic is to better define "protective thresholds" to guide the global response. We aimed to characterize the longitudinal dynamics of the antibody responses in naturally infected individuals in Chile and compared them to humoral responses induced after immunization with CoronaVac-based on an inactivated whole virus -or the BNT162b2- based on mRNA-vaccines. We also contrasted them with the respective effectiveness and efficacy data available for both vaccines. METHODS: We determined and compared the longitudinal neutralizing (nAb) and anti-nucleocapsid (anti-N) antibody responses of 74 COVID-19 individuals (37 outpatient and 37 hospitalized) during the acute disease and convalescence. We also assessed the antibody boosting of 36 of these individuals who were immunized after convalescence with either the CoronaVac (n = 30) or the BNT162b2 (n = 6) vaccines. Antibody titres were also measured for 50 naïve individuals immunized with two doses of CoronaVac (n = 35) or BNT162b2 (n = 15) vaccines. The neutralizing level after vaccination was compared to those of convalescent individuals and the predicted efficacy was estimated. FINDINGS: SARS-CoV-2 infection induced robust nAb and anti-N antibody responses lasting >9 months, but showing a rapid nAb decay. After convalescence, nAb titres were significantly boosted by vaccination with CoronaVac or BNT162b2. In naïve individuals, the calculated mean titre induced by two doses of CoronaVac or BNT162b2 was 0·2 times and 5.2 times, respectively, that of convalescent individuals, which has been proposed as threshold of protection. CoronaVac induced no or only modest anti-N antibody responses. Using two proposed logistic models, the predicted efficacy of BNT162b2 was estimated at 97%, in close agreement with phase 3 efficacy studies, while for CoronaVac it was ∼50% corresponding to the lowest range of clinical trials and below the real-life data from Chile (from February 2 through May 1, 2021 during the predominant circulation of the Gamma variant), where the estimated vaccine effectiveness to prevent COVID-19 was 62·8-64·6%. INTERPRETATION: The decay of nAbs titres in previously infected individuals over time indicates that vaccination is needed to boost humoral memory responses. Immunization of naïve individuals with two doses of CoronaVac induced nAbs titres that were significantly lower to that of convalescent patients, and similar to vaccination with one dose of BTN162b2. The real life effectiveness for CoronaVac in Chile was higher than estimated; indicating that lower titres and additional cellular immune responses induced by CoronaVac might afford protection in a highly immunized population. Nevertheless, the lower nAb titre induced by two doses of CoronaVac as compared to the BTN162b2 vaccine in naïve individuals, highlights the need of booster immunizations over time to maintain protective levels of antibody, particularly with the emergence of new SARS-CoV-2 variants. FUNDING: FONDECYT 1161971, 1212023, 1181799, FONDECYT Postdoctorado 3190706 and 3190648, ANID Becas/Doctorado Nacional 21212258, PIA ACT 1408, CONICYT REDES180170, Centro Ciencia & Vida, FB210008, Financiamiento Basal para Centros Científicos y Tecnológicos de Excelencia grants from the Agencia Nacional de Investigación y Desarrollo (ANID) of Chile; NIH-NIAD grants U19AI135972, R01AI132633 and contracts HHSN272201400008C and 75N93019C00051; the JPB Foundation, the Open Philanthropy Project grant 2020-215611 (5384); and by anonymous donors. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacuna BNT162 , COVID-19/prevención & control , Vacunas contra la COVID-19 , Convalecencia , Humanos
9.
Front Immunol ; 13: 796481, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35197972

RESUMEN

The coronavirus disease 2019 (COVID19) pandemic has left researchers scrambling to identify the humoral immune correlates of protection from COVID-19. To date, the antibody mediated correlates of virus neutralization have been extensively studied. However, the extent that non-neutralizing functions contribute to anti-viral responses are ill defined. In this study, we profiled the anti-spike antibody subtype/subclass responses, along with neutralization and antibody-dependent natural killer cell functions in 83 blood samples collected between 4 and 201 days post-symptoms onset from a cohort of COVID-19 outpatients. We observed heterogeneous humoral responses against the acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Overall, anti-spike profiles were characterized by a rapid rise of IgA and sustained IgG titers. In addition, strong antibody-mediated natural killer effector responses correlated with milder disease and being female. While higher neutralization profiles were observed in males along with increased severity. These results give an insight into the underlying function of antibodies beyond neutralization and suggest that antibody-mediated natural killer cell activity is a key function of the humoral response against the SARS-CoV-2 spike protein.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , Convalecencia , Células Asesinas Naturales/inmunología , Pacientes Ambulatorios , SARS-CoV-2/inmunología , Adulto , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , COVID-19/sangre , Femenino , Células HEK293 , Humanos , Masculino , Persona de Mediana Edad , SARS-CoV-2/metabolismo
10.
Viruses ; 14(2)2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35215895

RESUMEN

The emergence of new SARS-CoV-2 variants represents a constant threat to world public health. The SARS-CoV-2 Delta variant was identified in late 2020 in India; since then, it has spread to many other countries, replacing other predominant lineages and raising concerns about vaccination efficiency. We evaluated the sensitivity of the Delta variant to antibodies elicited by COVID-19 vaccinated (CoronaVac and ChAdOx1) and convalescent individuals previously infected by earlier lineages and by the Gamma variant. No reduction in the neutralizing efficacy of the Delta variant was observed when compared to B lineage and a reduced neutralization was observed for the Gamma variant. Our results indicate that neutralization of the Delta variant is not compromised in individuals vaccinated by CoronaVac or ChAdOx1; however, a reduction in neutralization efficacy is expected for individuals infected by the Gamma variant, highlighting the importance of continuous vaccination even for previously infected individuals.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Vacunas contra la COVID-19/inmunología , ChAdOx1 nCoV-19/inmunología , SARS-CoV-2/inmunología , Adulto , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/clasificación , ChAdOx1 nCoV-19/administración & dosificación , Convalecencia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Neutralización , SARS-CoV-2/genética , Vacunación
11.
La Habana; OPS; 2022.
Monografía en Español | PAHO-IRIS | ID: phr2-56494

RESUMEN

[Introducción] “Andar la salud” es un boletín elaborado en la Oficina de la Organización Panamericana de la Salud/Organización Mundial de la Salud (OPS/OMS) en Cuba. Su propósito fundamental es compartir lo más relevante de la cooperación técnica de esta Representación con el Ministerio de Salud Pública (MINSAP) y otras instituciones y organismos en el país. Desde que comenzó la pandemia provocada por el SARS-CoV-2 en la isla, esta publicación se ha dedicado, fundamentalmente, a compilar y dar a conocer aspectos destacados de la respuesta en el territorio nacional. Sin embargo, como en el país la COVID-19 ha tenido una tendencia al control en los últimos meses, los temas tratados en las ediciones del boletín se han diversificado más. En el presente número, por ejemplo, hay un artículo que resume cómo se desarrolló la 75ª Asamblea Mundial de Salud y otro dedicado a la 170a sesión del Comité Ejecutivo de la OPS, ambos eventos con participación de Cuba. Asimismo, se presentan algunos resultados de la Encuesta Nacional de Salud; se comenta la estrategia de enfrentamiento a las Enfermedades No Trasmisibles; se expone la situación del dengue en la región y en Cuba, entre otros contenidos que invitamos a leer.


Asunto(s)
Epidemias , SARS-CoV-2 , COVID-19 , Liderazgo , Enfermedades no Transmisibles , Convalecencia , Vulnerabilidad en Salud , Cooperación Técnica , Contaminación Ambiental , Medio Ambiente y Salud Pública , Epidemiología , Mpox
12.
Front Immunol ; 12: 769059, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34745145

RESUMEN

The prognosis of severe COVID-19 patients has motivated research communities to uncover mechanisms of SARS-CoV-2 pathogenesis also on a regional level. In this work, we aimed to understand the immunological dynamics of severe COVID-19 patients with different degrees of illness, and upon long-term recovery. We analyzed immune cellular subsets and SARS-CoV-2-specific antibody isotypes of 66 COVID-19 patients admitted to the Hospital Clínico Universidad de Chile, which were categorized according to the WHO ten-point clinical progression score. These included 29 moderate patients (score 4-5) and 37 severe patients under either high flow oxygen nasal cannula (18 patients, score 6), or invasive mechanical ventilation (19 patients, score 7-9), plus 28 convalescent patients and 28 healthy controls. Furthermore, six severe patients that recovered from the disease were longitudinally followed over 300 days. Our data indicate that severe COVID-19 patients display increased frequencies of plasmablasts, activated T cells and SARS-CoV-2-specific antibodies compared to moderate and convalescent patients. Remarkably, within the severe COVID-19 group, patients rapidly progressing into invasive mechanical ventilation show higher frequencies of plasmablasts, monocytes, eosinophils, Th1 cells and SARS-CoV-2-specific IgG than patients under high flow oxygen nasal cannula. These findings demonstrate that severe COVID-19 patients progressing into invasive mechanical ventilation show a distinctive type of immunity. In addition, patients that recover from severe COVID-19 begin to regain normal proportions of immune cells 100 days after hospital discharge and maintain high levels of SARS-CoV-2-specific IgG throughout the study, which is an indicative sign of immunological memory. Thus, this work can provide useful information to better understand the diverse outcomes of severe COVID-19 pathogenesis.


Asunto(s)
COVID-19/inmunología , Eosinófilos/inmunología , Células Plasmáticas/inmunología , SARS-CoV-2/fisiología , Células TH1/inmunología , Anciano , Anticuerpos Antivirales/sangre , Convalecencia , Progresión de la Enfermedad , Femenino , Humanos , Inmunidad Celular , Inmunoglobulina G/sangre , Memoria Inmunológica , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
14.
Biomedica ; 40(Supl. 2): 148-158, 2020 10 30.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33152198

RESUMEN

Introduction: SARS-CoV-2 has been identified as the new coronavirus causing an outbreak of acute respiratory disease in China in December, 2019. This disease, currently named COVID-19, has been declared as a pandemic by the World Health Organization (WHO). The first case of COVID-19 in Colombia was reported on March 6, 2020. Here we characterize an early SARS-CoV-2 isolate from the pandemic recovered in April, 2020. Objective: To describe the isolation and characterization of an early SARS-CoV-2 isolate from the epidemic in Colombia. Materials and methods: A nasopharyngeal specimen from a COVID-19 positive patient was inoculated on different cell lines. To confirm the presence of SARS-CoV-2 on cultures we used qRT-PCR, indirect immunofluorescence assay, transmission and scanning electron microscopy, and next-generation sequencing. Results: We determined the isolation of SARS-CoV-2 in Vero-E6 cells by the appearance of the cytopathic effect three days post-infection and confirmed it by the positive results in the qRT-PCR and the immunofluorescence with convalescent serum. Transmission and scanning electron microscopy images obtained from infected cells showed the presence of structures compatible with SARS-CoV-2. Finally, a complete genome sequence obtained by next-generation sequencing allowed classifying the isolate as B.1.5 lineage. Conclusion: The evidence presented in this article confirms the first isolation of SARSCoV-2 in Colombia. In addition, it shows that this strain behaves in cell culture in a similar way to that reported in the literature for other isolates and that its genetic composition is consistent with the predominant variant in the world. Finally, points out the importance of viral isolation for the detection of neutralizing antibodies, for the genotypic and phenotypic characterization of the strain and for testing compounds with antiviral potential.


Introducción. El nuevo coronavirus causante de un brote de enfermedad respiratoria aguda en China en diciembre de 2019 se identificó como SARS-CoV-2. La enfermedad, denominada COVID-19, fue declarada pandemia por la Organización Mundial de la Salud (OMS). El primer caso de COVID-19 en Colombia se reportó el 6 de marzo de 2020; en este estudio se caracterizó un aislamiento temprano del virus SARS-CoV-2 de una muestra ecolectada en abril de 2020. Objetivos. Describir y caracterizar una cepa temprana a partir de un aislamiento de SARSCoV-2 durante la pandemia en Colombia. Materiales y métodos. Se obtuvo una muestra de un paciente con COVID-19 confirmada por qRT-PCR; la muestra fue inoculada en diferentes líneas celulares hasta la aparición del efecto citopático. Para confirmar la presencia de SARS-CoV-2 en el cultivo, se utilizó la qRT-PCR a partir de los sobrenadantes, la inmunofluorescencia indirecta (IFI) en células Vero-E6, así como microscopía electrónica y secuenciación de nueva generación (nextgeneration sequencing). Resultados. Se confirmó el aislamiento de SARS-CoV-2 en células Vero-E6 por la aparición del efecto citopático tres días después de la infección, así como mediante la qRT-PCR y la IFI positiva con suero de paciente convaleciente positivo para SARS-CoV-2. Además, en las imágenes de microscopía electrónica de trasmisión y de barrido de células infectadas se observaron estructuras compatibles con viriones de SARS-CoV-2. Por último, se obtuvo la secuencia completa del genoma, lo que permitió clasificar el aislamiento como linaje B.1.5. Conclusiones. La evidencia presentada en este artículo permite confirmar el primer aislamiento de SARS-CoV-2 en Colombia. Además, muestra que esta cepa se comporta en cultivo celular de manera similar a lo reportado en la literatura para otros aislamientos y que su composición genética está acorde con la variante predominante en el mundo. Finalmente, se resalta la importancia que tiene el aislamiento viral para la detección de anticuerpos, para la caracterización genotípica y fenotípica de la cepa y para probar compuestos con potencial antiviral.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/virología , Pandemias , Neumonía Viral/virología , ARN Viral/genética , Animales , Betacoronavirus/genética , Betacoronavirus/fisiología , Betacoronavirus/ultraestructura , COVID-19 , Chlorocebus aethiops , Colombia/epidemiología , Convalecencia , Infecciones por Coronavirus/epidemiología , Efecto Citopatogénico Viral , Técnica del Anticuerpo Fluorescente Indirecta , Genoma Viral , Humanos , Microscopía Electrónica , Tipificación Molecular , Nasofaringe/virología , Neumonía Viral/epidemiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2 , Análisis de Secuencia de ARN , Especificidad de la Especie , Células Vero , Virión/ultraestructura , Cultivo de Virus
15.
Transfusion ; 60(12): 2938-2951, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32935877

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) collection began in two Brazilian hospitals for treatment of severe/critical patients. METHODS AND MATERIALS: Mild/moderate COVID-19 convalescents were selected as CCP donors after reverse transcription polymerase chain reaction (RT-PCR) confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and absence of symptoms for ≥14 days plus (a) age (18-60 years), body weight greater than 55 kg; (b) immunohematological studies; (c) no infectious markers of hepatitis B virus, hepatitis C virus, human immunodeficiency virus, human T-lymphotropic virus-1/2, Chagas and syphilis infection; (d) no HLA antibodies (multiparous); (e) second RT-PCR (nasopharyngeal swab and/or blood) negativity; (f) virus neutralization test (cytopathic effect-based virus neutralization test neutralizing antibody) and anti-nucleocapsid protein SARS-CoV-2 IgM, IgG, and IgA enzyme-linked immunosorbent assays. RESULTS: Among 271 donors (41 females, 230 males), 250 presented with neutralizing antibodies. Final RT-PCR was negative on swab (77.0%) or blood (88.4%; P = .46). Final definition of RT-PCR was only defined at more than 28 days after full recovery in 59 of 174 (33.9%) RT-PCR -ve, and 25/69 RT-PCR +ve (36.2%; 13 between 35 and 48 days). Neutralizing antibody titers of 160 or greater were found in 63.6%. Correlation between IgG signal/cutoff of 5.0 or greater and neutralizing antibody of 160 or greater was 82.4%. Combination of final RT-PCR -ve with neutralizing antibody ≥160 was 41.3% (112/271). Serial plasma collection showed decline in neutralizing antibody titers and IgA levels (P < .05), probably denoting a "golden period" for CCP collection (≤28 days after joining the program); IgA might have an important role as neutralizing antibody. Donor's weight, days between disease onset and serial plasma collection, and IgG and IgM levels are important predictors for neutralizing antibody titer. CONCLUSIONS: RT-PCR +ve cases are still detected in 36.2% within 28 to 48 days after recovery. High anti-nucleocapsid protein IgG levels may be used as a surrogate marker to neutralizing antibody.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Prueba Serológica para COVID-19 , COVID-19/sangre , COVID-19/terapia , Convalecencia , Selección de Donante/estadística & datos numéricos , SARS-CoV-2/inmunología , Adulto , Donantes de Sangre , Brasil/epidemiología , COVID-19/inmunología , Prueba de Ácido Nucleico para COVID-19 , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunización Pasiva , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2/aislamiento & purificación , Factores de Tiempo , Adulto Joven , Sueroterapia para COVID-19
16.
Rev. chil. obstet. ginecol. (En línea) ; Rev. chil. obstet. ginecol;85(supl.1): S23-S27, set. 2020. tab
Artículo en Español | LILACS | ID: biblio-1138645

RESUMEN

INTRODUCCIÓN Y OBJETIVOS: COVID-19 es una patología producida por el virus RNA SARS-CoV-2, declarada pandemia por la OMS en marzo de 2020. La literatura mundial describe mayor incidencia de parto prematuro y cesáreas en pacientes infectadas por COVID-19 principalmente de origen iatrogénico, sin embargo, existen escasos datos del pronóstico del embarazo al decidir diferir el parto hasta después del período infeccioso del virus. Este trabajo reporta un grupo de embarazadas diagnosticadas con COVID-19 en tercer trimestre donde se decidió no interrumpir el embarazo y diferir su parto hasta recuperación de la patología. MÉTODOS: Estudio observacional retrospectivo que analiza resultados materno-perinatales en 9 casos de mujeres infectadas por COVID, diagnosticadas posterior a las 33 semanas y cuyo parto se verificó después de recuperadas del COVID. RESULTADOS: Se observó un 77% de pacientes sintomáticas, 77% requirieron hospitalización, 33% por COVID, todas ingresaron a unidad de paciente crítico, sólo una requirió ventilación mecánica no invasiva. Dos cursaron con cetoacidosis normo-glicémica y dos con neumonía por COVID-19. Un 88% resultó en parto de término, sólo una paciente tuvo parto prematuro de causa obstétrica. La vía de parto fue un 67% vaginal y 33% por cesárea, todas por indicación obstétrica. La latencia al parto promedio fue de 17.3 días. Los puntajes de Apgar fueron todos mayor a 7 al minuto y 5 minutos. CONCLUSIÓN: Los resultados de esta serie sugieren que, en casos seleccionados, los partos posteriores al período infeccioso del COVID se asocian a buenos resultados materno-perinatales, sin embargo, resulta importante aumentar la casuística.


INTRODUCTION AND OBJECTIVES: COVID-19 is a pathology produced by the RNA virus SARS-CoV-2, declared a pandemic by the WHO in March of 2020. The world literature describes more preterm birth and caesarean section in pregnant women infected by COVID-19, principally by medical indication, but it has not been described in depth what happens when we differ delivery after the infectious period. This report reviews a subgroup of patients who were diagnosed with COVID-19 in the third trimester and decided to differ birth until they recovered from the disease. METHODS: Retrospective observational study that analyzes maternal and perinatal outcome of 9 women who were diagnosed with COVID-19 after the 33 weeks of pregnancy, decided to differ delivery and had their birth recovered from the disease. RESULTS: We observed 77% of patients symptomatic, 77% required hospitalization, 33% because of COVID, all admited to critical patient care, only one required non invasive mechanical ventilation. 2 patients suffered normoglycemic ketoacidosis, 2 had COVID-19 pneumonia. An 88% resulted in term birth, only 1 was prematurely interrupted by obstetric cause. 66% patients had vaginal delivery and 33.3% caesarean section, all by obstetric cause. The average latency to birth was 17.3 days. Apgar scores were all more than 7 at minute 1 and 5. CONCLUSION: The results of this series suggest that in selected cases where the clinical characteristics allow it, to differ interruption of pregnancy until after the infectious period can associate to good outcomes of maternal and neonatal morbimortality, however, it's fundamental to continue research.


Asunto(s)
Humanos , Femenino , Embarazo , Adulto , Adulto Joven , Neumonía Viral/complicaciones , Complicaciones Infecciosas del Embarazo/terapia , Complicaciones Infecciosas del Embarazo/virología , Resultado del Embarazo , Convalecencia , Infecciones por Coronavirus/complicaciones , Tercer Trimestre del Embarazo , Pronóstico , Cesárea , Estudios Retrospectivos , Pandemias , Betacoronavirus , Hospitalización
17.
Am J Trop Med Hyg ; 103(4): 1597-1599, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32815513

RESUMEN

COVID-19, designated as SARS-CoV-2, has caused millions of infections worldwide, including in patients with concomitant infections. Here, we report two unusual cases of patients with triple infections of SARS-CoV-2, Mycobacterium tuberculosis, and HIV. Both cases were confirmed through microbiological and immunological studies. The acute respiratory phase in both patients was treated with supplemental oxygen. Antituberculosis and antiretroviral therapies were started simultaneously. In 2 weeks, both patients demonstrated clinical improvement and recovery from COVID-19. Our findings suggest that even in cases of triple infection, clinical management together with respiratory therapy contributes to patient survival.


Asunto(s)
Antituberculosos/uso terapéutico , Antivirales/uso terapéutico , Infecciones por Coronavirus/terapia , Infecciones por VIH/terapia , Heparina/uso terapéutico , Hidroxicloroquina/uso terapéutico , Neumonía Viral/terapia , Tuberculosis Pulmonar/terapia , Adulto , Betacoronavirus/patogenicidad , COVID-19 , Coinfección , Convalecencia , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/microbiología , Infecciones por Coronavirus/virología , VIH/patogenicidad , Infecciones por VIH/inmunología , Infecciones por VIH/microbiología , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/patogenicidad , Pandemias , Neumonía Viral/inmunología , Neumonía Viral/microbiología , Neumonía Viral/virología , Respiración con Presión Positiva/métodos , SARS-CoV-2 , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/microbiología , Tuberculosis Pulmonar/virología
18.
J Leukoc Biol ; 108(4): 1265-1277, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32726884

RESUMEN

Zika is an important emerging infectious disease in which the role of T cells remains elusive. This study aimed to evaluate the phenotype of multifunctional T cells in individuals 2 yr after exposure to Zika virus (ZIKV). We used a library of 671 synthetic peptides covering the whole polyprotein of ZIKV in pools corresponding to each viral protein (i.e., capsid, membrane precursor or prM, envelope, NS1 [nonstructural protein], NS2A + NS2B, NS3, NS4A + NS4B, and NS5) to stimulate PBMCs from individuals previously exposed to ZIKV. We observed an increased frequency of ZIKV-specific IFNγ, IL-17A, TNF, and IL-10 production by T cell populations. IFNγ and TNF production were especially stimulated by prM, capsid, or NS1 in CD8+ T cells and by capsid or prM in CD4+ T cells. In addition, there was an increase in the frequency of IL-10+ CD8+ T cells after stimulation with prM, capsid, NS1, NS3, or NS5. Multifunctional properties were observed in ZIKV-specific T cells responding especially to prM, capsid, NS1 or, to a smaller extent, NS3 antigens. For example, we found a consistent IFNγ + TNF+ CD8+ T cell population in response to most virus antigens and CD4+ and CD8+ T cells that were IFNγ + IL-17A+ and IL-17A+IL-10+, which could also produce TNF, in response to capsid, prM, NS1, or NS3 stimulation. Interestingly, CD8+ T cells were more prone to a multifunctional phenotype than CD4+ T cells, and multifunctional T cells were more efficient at producing cytokines than single-function cells. This work provides relevant insights into the quality of ZIKV-specific T cell responses and ZIKV immunity.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunidad Celular , Infección por el Virus Zika/inmunología , Virus Zika/inmunología , Adolescente , Adulto , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/patología , Convalecencia , Citocinas/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas Virales/inmunología , Infección por el Virus Zika/patología
19.
Rev Invest Clin ; 72(3): 159-164, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32584322

RESUMEN

BACKGROUND: The ideal treatment of coronavirus disease (COVID)-19 has yet to be defined, but convalescent plasma (CoPla) has been successfully employed. OBJECTIVE: The objective of the study was to study the safety and outcomes of the administration of CoPla to individuals with severe COVID-19 in an academic medical center. METHODS: Ten patients were prospectively treated with plasma from COVID-19 convalescent donors. RESULTS: Over 8 days, the sequential organ failure assessment score dropped significantly in all patients, from 3 to 1.5 (p = 0.014); the Kirby index (PaO2/FiO2) score increased from 124 to 255, (p < 0.0001), body temperature decreased significantly from 38.1 to 36.9°C (p = 0.0058), and ferritin levels also dropped significantly from 1736.6 to 1061.8 ng/ml (p = 0.0001). Chest X-rays improved in 7/10 cases and in 6/10, computerized tomography scans also revealed improvement of the lung injury. Decreases in C-reactive protein and D-dimer levels were also observed. Three of five patients on mechanical ventilation support could be extubated, nine were transferred to conventional hospital floors, and six were sent home; two patients died. The administration of CoPla had no side effects and the 24-day overall survival was 77%. CONCLUSIONS: Although other treatments were also administered to the patients and as a result data are difficult to interpret, it seems that the addition of CoPla improved pulmonary function.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/terapia , Neumonía Viral/terapia , Adulto , Anciano , Anticuerpos Antivirales/sangre , Betacoronavirus/inmunología , Betacoronavirus/aislamiento & purificación , Biomarcadores , Temperatura Corporal , Proteína C-Reactiva/análisis , COVID-19 , Terapia Combinada , Convalecencia , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/diagnóstico por imagen , Infecciones por Coronavirus/tratamiento farmacológico , Femenino , Ferritinas/sangre , Humanos , Inmunización Pasiva , Estimación de Kaplan-Meier , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Pandemias , Proyectos Piloto , Plasma , Neumonía Viral/sangre , Neumonía Viral/diagnóstico por imagen , Neumonía Viral/tratamiento farmacológico , Estudios Prospectivos , Respiración Artificial , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven , Tratamiento Farmacológico de COVID-19 , Sueroterapia para COVID-19
20.
Rev. invest. clín ; Rev. invest. clín;72(3): 159-164, May.-Jun. 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1251850

RESUMEN

ABSTRACT Background: The ideal treatment of coronavirus disease (COVID)-19 has yet to be defined, but convalescent plasma (CoPla) has been successfully employed. Objective: The objective of the study was to study the safety and outcomes of the administration of CoPla to individuals with severe COVID-19 in an academic medical center. Methods: Ten patients were prospectively treated with plasma from COVID-19 convalescent donors. Results: Over 8 days, the sequential organ failure assessment score dropped significantly in all patients, from 3 to 1.5 (p = 0.014); the Kirby index (PaO2/FiO2) score increased from 124 to 255, (p < 0.0001), body temperature decreased significantly from 38.1 to 36.9°C (p = 0.0058), and ferritin levels also dropped significantly from 1736.6 to 1061.8 ng/ml (p = 0.0001). Chest X-rays improved in 7/10 cases and in 6/10, computerized tomography scans also revealed improvement of the lung injury. Decreases in C-reactive protein and D-dimer levels were also observed. Three of five patients on mechanical ventilation support could be extubated, nine were transferred to conventional hospital floors, and six were sent home; two patients died. The administration of CoPla had no side effects and the 24-day overall survival was 77%. Conclusions: Although other treatments were also administered to the patients and as a result data are difficult to interpret, it seems that the addition of CoPla improved pulmonary function.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Adulto Joven , Neumonía Viral/terapia , Infecciones por Coronavirus/terapia , Betacoronavirus/aislamiento & purificación , Betacoronavirus/inmunología , Plasma , Índice de Severidad de la Enfermedad , Temperatura Corporal , Proteína C-Reactiva/análisis , Biomarcadores , Tomografía Computarizada por Rayos X , Proyectos Piloto , Convalecencia , Inmunización Pasiva , Resultado del Tratamiento , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/diagnóstico por imagen , Terapia Combinada , Estimación de Kaplan-Meier , Ferritinas/sangre , Pandemias , SARS-CoV-2 , COVID-19 , Pulmón/diagnóstico por imagen , Anticuerpos Antivirales/sangre
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