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1.
Nat Commun ; 11(1): 4698, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943630

RESUMO

Given the limited availability of serological testing to date, the seroprevalence of SARS-CoV-2-specific antibodies in different populations has remained unclear. Here, we report very low SARS-CoV-2 seroprevalence in two San Francisco Bay Area populations. Seroreactivity was 0.26% in 387 hospitalized patients admitted for non-respiratory indications and 0.1% in 1,000 blood donors in early April 2020. We additionally describe the longitudinal dynamics of immunoglobulin-G (IgG), immunoglobulin-M (IgM), and in vitro neutralizing antibody titers in COVID-19 patients. The median time to seroconversion ranged from 10.3-11.0 days for these 3 assays. Neutralizing antibodies rose in tandem with immunoglobulin titers following symptom onset, and positive percent agreement between detection of IgG and neutralizing titers was >93%. These findings emphasize the importance of using highly accurate tests for surveillance studies in low-prevalence populations, and provide evidence that seroreactivity using SARS-CoV-2 anti-nucleocapsid protein IgG and anti-spike IgM assays are generally predictive of in vitro neutralizing capacity.


Assuntos
Anticorpos Neutralizantes/sangue , Betacoronavirus/imunologia , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Anticorpos Antivirais/imunologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/imunologia , São Francisco/epidemiologia , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Testes Sorológicos/métodos
2.
Pain Physician ; 23(4S): S381-S390, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32942795

RESUMO

BACKGROUND: The interventional pain management community saw the COVID-19 pandemic decimate elective interventional procedures and new patient visits across the United States until the reopening of America and the restarting of interventional procedures and elective surgical procedures began again. Health care providers, along with essential workers and patients, continue to be concerned about functioning in a safe and responsible manner. Consequently, a level of comfort is created by the testing health care workers with long exposure to new patients and patients undergoing interventions in high risk environments. As the United States and the world suffers from an ongoing infodemic, there are substantial amounts of misinformation, and some appropriate information being produced on molecular, antigen and antibody testing. Consequently, this manuscript is undertaken to describe the value and validity of coronavirus antibody testing. METHODS: Literature review. RESULTS: Antibody tests detect antibodies or immunoglobulins that are produced as the human immune response to SARS-CoV-2 infection. A positive result suggests that the individual has potentially been exposed to SARS-CoV-2. When immunoglobulins M (IgM) antibodies are present, they can indicate an active or recent infection, whereas immunoglobulin G (IgG) antibodies show up later in the infection process and can often indicate a past infection, but does not exclude recently infected patients who can still be contagious, especially when IgM antibodies are also concurrently detected. While past knowledge indicates that for viral infections, IgG antibodies usually persist longer than IgM antibodies and provide immunity from re-infection, it is not clearly known if that is true for COVID-19. LIMITATIONS: A narrative review with paucity of literature. CONCLUSION: Antibody tests have been developed to detect IgG only, both IgG and IgM, or total antibodies. At present, multiple antibody tests are available for use in the United States. In a review of 54 available studies through the end of April, mostly from China, the accuracy of pooled results for combination IgG/IgM tests was 91.4% (95% CI, 87.0 - 96.6) for 15 to 21 days post-symptom onset. Thus, antibody tests provide a promise and a peril in the ongoing Covid-19 pandemic.


Assuntos
Anticorpos Antivirais/sangue , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Anticorpos Antivirais/imunologia , Betacoronavirus , China , Infecções por Coronavirus/sangue , Infecções por Coronavirus/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/imunologia , Sensibilidade e Especificidade
3.
Iran J Kidney Dis ; 14(5): 389-398, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32943594

RESUMO

INTRODUCTION: Seven months after the emergence of SARS-COV-2 virus, there is paucity of data regarding the epidemiology of the virus in hemodialysis patients. We aim to present the results of the screening program implied after outbreak of COVID-19 in a referral hemodialysis ward. METHODS: We started clinical screening and obligatory mask wearing for dialysis patients and personnel on 20-Feb-2020. However 11 symptomatic COVID-19 patients emerged till day +36. On days +39 and +40 a screening program was implied including measurement of SARS-COV-2 PCR and immunoglobulin G and M (IgG/IgM) and chest computerized tomography (CCT) scan. The results of CCT scan, classified according to the coronavirus disease 2019 (COVID-19) Reporting and Data System (CO-RADS) classification; as with very low (grade 1-normal), low, indeterminate, high, and very high likelihood of COVID-19 (grades 2, 3, 4, and 5; respectively), were used for compartmentalization of patients. RESULTS: Among 178 patients (68.2% male, mean age = 58.7 ± 16.6 years), 11 got COVID-19 before screening, two of whom died. CCT scans were normal in 71.3% and grade 2, 3, 4, and 5 in 7.9%, 4.5%, 5.6%, and 10.7%; respectively. PCR and IgG and/or IgM were positive in 27 and 32 patients. Eighty-three patients had evidence of COVID-19 infection, who were significantly older (62.2 ± 16.6 vs. 56.1 ± 16.02, P < .05). There was no difference in the rate of infection considering gender, diabetes mellitus, hypertension and different blood groups. CONCLUSION: Asymptomatic SARS- COV 2 infection may affect a large number of dialysis patients. We highly recommend a screening strategy whenever the number of patients is increasing.


Assuntos
Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Pessoal de Saúde , Unidades Hospitalares de Hemodiálise , Falência Renal Crônica/terapia , Pulmão/diagnóstico por imagem , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , Betacoronavirus/genética , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/complicações , Infecções por Coronavirus/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Incidência , Irã (Geográfico)/epidemiologia , Falência Renal Crônica/complicações , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/imunologia , Diálise Renal , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tomografia Computadorizada por Raios X , Adulto Jovem
4.
PLoS Pathog ; 16(8): e1008732, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32750093

RESUMO

Rotavirus is a major cause of gastroenteritis in children, with infection typically inducing high levels of protective antibodies. Antibodies targeting the middle capsid protein VP6 are particularly abundant, and as VP6 is only exposed inside cells, neutralisation must be post-entry. However, while a system of poly immune globulin receptor (pIgR) transcytosis has been proposed for anti-VP6 IgAs, the mechanism by which VP6-specific IgG mediates protection remains less clear. We have developed an intracellular neutralisation assay to examine how antibodies neutralise rotavirus inside cells, enabling comparison between IgG and IgA isotypes. Unexpectedly we found that neutralisation by VP6-specific IgG was much more efficient than by VP6-specific IgA. This observation was highly dependent on the activity of the cytosolic antibody receptor TRIM21 and was confirmed using an in vivo model of murine rotavirus infection. Furthermore, mice deficient in only IgG and not other antibody isotypes had a serious deficit in intracellular antibody-mediated protection. The finding that VP6-specific IgG protect mice against rotavirus infection has important implications for rotavirus vaccination. Current assays determine protection in humans predominantly by measuring rotavirus-specific IgA titres. Measurements of VP6-specific IgG may add to existing mechanistic correlates of protection.


Assuntos
Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Proteínas do Capsídeo/imunologia , Imunoglobulina G/imunologia , Infecções por Rotavirus/imunologia , Rotavirus/fisiologia , Animais , Antígenos Virais/genética , Proteínas do Capsídeo/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Rotavirus/genética , Infecções por Rotavirus/virologia , Especificidade da Espécie
5.
Nat Commun ; 11(1): 4198, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32826914

RESUMO

COVID-19 caused by SARS-CoV-2 has become a global pandemic requiring the development of interventions for the prevention or treatment to curtail mortality and morbidity. No vaccine to boost mucosal immunity, or as a therapeutic, has yet been developed to SARS-CoV-2. In this study, we discover and characterize a cross-reactive human IgA monoclonal antibody, MAb362. MAb362 binds to both SARS-CoV and SARS-CoV-2 spike proteins and competitively blocks ACE2 receptor binding, by overlapping the ACE2 structural binding epitope. Furthermore, MAb362 IgA neutralizes both pseudotyped SARS-CoV and SARS-CoV-2 in 293 cells expressing ACE2. When converted to secretory IgA, MAb326 also neutralizes authentic SARS-CoV-2 virus while the IgG isotype shows no neutralization. Our results suggest that SARS-CoV-2 specific IgA antibodies, such as MAb362, may provide effective immunity against SARS-CoV-2 by inducing mucosal immunity within the respiratory system, a potentially critical feature of an effective vaccine.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Betacoronavirus/imunologia , Imunoglobulina A/imunologia , Peptidil Dipeptidase A/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/metabolismo , Chlorocebus aethiops , Reações Cruzadas , Epitopos , Células HEK293 , Humanos , Imunoglobulina A/metabolismo , Imunoglobulina A Secretora/imunologia , Imunoglobulina A Secretora/metabolismo , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Modelos Moleculares , Mutação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Vírus da SARS/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero
6.
Medicine (Baltimore) ; 99(34): e21936, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846862

RESUMO

RATIONALE: IgG4-related disease (IgG4-RD) is a systemic disease that can involve various organs and is characterized by the infiltrations of IgG4-positive plasma cells and lymphocytes, fibrosis, and elevated serum IgG4 levels. IgG4-related sclerosing cholangitis (IgG4-RSC) is a subtype of IgG4-RD. No certain relationship between IgG4-RSC and cholangiocarcinoma has been established as yet, and there have been few reports of the simultaneous diagnosis of IgG4-RSC and cholangiocarcinoma. PATIENT CONCERNS: A 76-year-old male visited our gastroenterology department due to the recent occurrence of pruritus and jaundice. DIAGNOSIS: Computed tomography (CT) scan showed ductal wall swelling and enhancement from both intrahepatic duct confluence to the common bile duct, upper biliary dilatation, and accompanying autoimmune pancreatitis (a sub type of IgG4-RD). Biopsy of the distal common bile duct by endoscopic retrograde cholangiopancreatography (ERCP) resulted in a diagnosis of IgG4-RSC. Subsequently, adenocarcinoma was identified by repeated cytology of bile juice. Finally, Klatskin tumor type IIIA and IgG4-RSC were concurrently diagnosed. INTERVENTIONS: IgG4-RSC was treated with steroid and Klatskin tumors by gemcitabine + cisplatin chemotherapy. OUTCOMES: The jaundice had improved and CT showed substantial improvement of the intrahepatic duct dilatation. LESSONS: IgG4-RSC and cholangiocarcinoma are easily confused, but their treatments are quite different, and thus, care must be taken during diagnosis. Furthermore, these 2 diseases may co-exist. Therefore, even if IgG4-RSC is diagnosed first, the possibility of accompanying cholangiocarcinoma should be thoroughly investigated.


Assuntos
Colangiocarcinoma/complicações , Colangite Esclerosante/patologia , Imunoglobulina G/imunologia , Tumor de Klatskin/complicações , Tumor de Klatskin/patologia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Colangiocarcinoma/patologia , Colangiopancreatografia Retrógrada Endoscópica , Colangite Esclerosante/diagnóstico por imagem , Colangite Esclerosante/tratamento farmacológico , Cisplatino/uso terapêutico , Ducto Colédoco/patologia , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Diagnóstico Diferencial , Humanos , Doença Relacionada a Imunoglobulina G4/patologia , Icterícia/diagnóstico , Icterícia/etiologia , Tumor de Klatskin/classificação , Tumor de Klatskin/tratamento farmacológico , Masculino , Prurido/diagnóstico , Prurido/etiologia , Esteroides/uso terapêutico , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
Nature ; 584(7820): 274-278, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760003

RESUMO

Colonization by the microbiota causes a marked stimulation of B cells and induction of immunoglobulin, but mammals colonized with many taxa have highly complex and individualized immunoglobulin repertoires1,2. Here we use a simplified model of defined transient exposures to different microbial taxa in germ-free mice3 to deconstruct how the microbiota shapes the B cell pool and its functional responsiveness. We followed the development of the immunoglobulin repertoire in B cell populations, as well as single cells by deep sequencing. Microbial exposures at the intestinal mucosa generated oligoclonal responses that differed from those of germ-free mice, and from the diverse repertoire that was generated after intravenous systemic exposure to microbiota. The IgA repertoire-predominantly to cell-surface antigens-did not expand after dose escalation, whereas increased systemic exposure broadened the IgG repertoire to both microbial cytoplasmic and cell-surface antigens. These microbial exposures induced characteristic immunoglobulin heavy-chain repertoires in B cells, mainly at memory and plasma cell stages. Whereas sequential systemic exposure to different microbial taxa diversified the IgG repertoire and facilitated alternative specific responses, sequential mucosal exposure produced limited overlapping repertoires and the attrition of initial IgA binding specificities. This shows a contrast between a flexible response to systemic exposure with the need to avoid fatal sepsis, and a restricted response to mucosal exposure that reflects the generic nature of host-microbial mutualism in the mucosa.


Assuntos
Linfócitos B/citologia , Linfócitos B/imunologia , Imunidade nas Mucosas/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Simbiose/imunologia , Administração Intravenosa , Administração Oral , Animais , Clostridiales/imunologia , Clostridiales/isolamento & purificação , Escherichia coli/imunologia , Escherichia coli/isolamento & purificação , Feminino , Vida Livre de Germes , Imunoglobulina A/química , Imunoglobulina A/imunologia , Imunoglobulina G/química , Imunoglobulina G/imunologia , Cadeias Pesadas de Imunoglobulinas/imunologia , Memória Imunológica/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasmócitos/citologia , Plasmócitos/imunologia , Priming de Repetição
8.
Front Immunol ; 11: 1888, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849647

RESUMO

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes severe respiratory tract infections in humans (COVID-19), has become a global health concern. Currently, several vaccine candidates against SARS-CoV-2 are in clinical trials but approval of these vaccines is likely to take a long time before they are available for public use. In a previous report, the importance of passive immunity and how immunoglobulin (Ig)G collected from recovered coronavirus patients could help in the protection against COVID-19 and boost the immune system of new patients was reported. Passive immunity by immunoglobulin transfer is a concept employed by most mammals and bovine IgG has a role to play in human therapy. IgG is one of the major components of the immunological activity found in cow's milk and colostrum. Heterologous transfer of passive immunity associated with the consumption of bovine immune milk by humans has been investigated for decades for its immunological activity against infections. This short review focuses on passive immunity and how microfiltered raw immune milk or colostrum collected from cows vaccinated against SARS-CoV-2 could provide short-term protection against SARS-CoV-2 infection in humans and could be used as an option until a vaccine becomes commercially available.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Ingestão de Líquidos/imunologia , Imunização Passiva/métodos , Leite/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Vacinação , Animais , Anticorpos Antivirais/imunologia , Bovinos , Colostro/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Feminino , Humanos , Imunoglobulina G/imunologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Vacinas Virais/imunologia
9.
Front Immunol ; 11: 1936, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849650

RESUMO

Background: The relationship between SARS-CoV-2-carrying time and specific antibody production has not yet been reported in re-admitted COVID-19 patients. We reported a case of mild COVID-19 with long virus-carrying time, weak production of virus-specific IgG and IgM antibodies, and recurrence of positive SARS-CoV-2 RNA in stool specimens after discharge. Case Presentation: A 27-year-old male was diagnosed as COVID-19 after returning to Meizhou from Wuhan. Despite extremely mild symptoms, the patient was hospitalized for 24 days because of persistent positive SARS-CoV-2 RNA detection. Three days after recovery discharge, he was hospitalized again for 7 days due to a recurrence of the positive SARS-CoV-2 RNA result, while in a good physical condition. Serological assay, using a fluorescent immunochromatography detection kit specific to SARS-CoV-2, showed that SARS-CoV-2-specific IgM antibodies were undetectable and IgG antibodies were very low on day 8 after onset; both of the antibodies seemingly reached top concentrations on day 15 (just a 6-fold increase of the IgG titer), and then decreased, remaining relatively stable from day 25 after onset until discharge. The production of the IgM and IgG targeting SARS-CoV-2 in this very mild case was much lower than that in a severe case of COVID-19 during the same hospitalizing period, and the latter was used as a control. Conclusion: Mild COVID-19 patients could carry SARS-CoV-2 for a long time, which may be related to the weak production of the virus-specific IgG and IgM. Recurrence of positive SARS-CoV-2 RNA could occur in mild COVID-19 possibly due to intermittent virus shedding, so strict quarantine and health surveillance should be taken for all discharged COVID-19 patients to prevent a potential virus spread.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Pneumonia Viral/imunologia , Adulto , Betacoronavirus/genética , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Humanos , Masculino , Pandemias , Alta do Paciente , Readmissão do Paciente , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Quarentena/métodos , RNA Viral/análise , Eliminação de Partículas Virais
10.
Monoclon Antib Immunodiagn Immunother ; 39(4): 107-111, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32762609

RESUMO

In this hypothesis, we address the biological/immunological pathway leading to severe disease or death after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The underlying immune response is described with "original antigenic sin" (OAS) whereby previous infections influence the response to future virus encounters. We cite evidence for OAS-induced immunopathology in HIV-1 disease. We hypothesize that similar immune abnormalities can occur after infection with SARS-CoV-2. This hypothesis is supported by recent analysis of the antibodies in infected patients demonstrating serological and B cell abnormalities. The concept of symmetrical clonal regulation developed earlier for the immune network illustrates the pathway suggested by our hypothesis and may be helpful to develop strategies avoiding severe coronavirus disease 2019.


Assuntos
Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Evasão da Resposta Imune/imunologia , Pneumonia Viral/imunologia , Anticorpos Monoclonais/imunologia , Infecções por Coronavirus/patologia , Reações Cruzadas/imunologia , Síndrome da Liberação de Citocina/imunologia , HIV/imunologia , HIV-1/imunologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Memória Imunológica/imunologia , Pandemias , Pneumonia Viral/patologia
11.
PLoS One ; 15(8): e0237671, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797068

RESUMO

In high malaria transmission settings, the use of sulfadoxine-pyrimethamine-based intermittent preventive treatment during pregnancy (IPTp-SP) has resulted in decreased antibody (Ab) levels to VAR2CSA. However, information of Ab levels in areas of low or intermediate malaria transmission after long-term implementation of IPTp-SP is still lacking. The present study sought to evaluate antibody prevalence and levels in women at delivery in Etoudi, a peri-urban area in the capital of Yaoundé, Cameroon, that is a relatively low-malaria transmission area. Peripheral plasma samples from 130 pregnant women were collected at delivery and tested for IgG to the full-length recombinant VAR2CSA (FV2) and its most immunogenic subdomain, DBL5. The study was conducted between 2013 and 2015, approximately ten years after implementation of IPTp-SP in Cameroon. About 8.6% of the women attending the clinic had placental malaria (PM). One, two or 3 doses of SP did not impact significantly on either the percentage of women with Ab to FV2 and DBL5 or Ab levels in Ab-positive women compared to women not taking SP. The prevalence of Ab to FV2 and DBL5 was only 36.9% and 36.1%, respectively. Surprisingly, among women who had PM at delivery, only 61.5% and 57.7% had Ab to FV2 and DBL5, respectively, with only 52.9% and 47.1% in PM-positive paucigravidae and 77.7% of multigravidae having Ab to both antigens. These results suggest that long-term implementation of IPTp-SP in a low-malaria transmission area results in few women having Ab to VAR2CSA.


Assuntos
Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Antimaláricos/uso terapêutico , Malária Falciparum/prevenção & controle , Complicações Parasitárias na Gravidez/prevenção & controle , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Adulto , Anticorpos Antiprotozoários/sangue , Camarões/epidemiologia , Combinação de Medicamentos , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Malária/sangue , Malária/epidemiologia , Malária/imunologia , Malária/prevenção & controle , Malária Falciparum/sangue , Malária Falciparum/epidemiologia , Malária Falciparum/imunologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/imunologia , Gravidez , Complicações Parasitárias na Gravidez/sangue , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/imunologia , Adulto Jovem
13.
Mem Inst Oswaldo Cruz ; 115: e200225, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813814

RESUMO

In the near future, the overlap of Coronavirus disease 2019 (COVID-19) and dengue epidemics is a concrete threat in tropical regions. Co-epidemics of COVID-19 and dengue could be an overwhelming challenge for health systems in low- and middle-income countries. In this work, we investigated potential serological cross-reactions between COVID-19 and dengue patients. Among 32 COVID-19 positive sera, no positive Dengue virus (DENV) IgG/IgM results were observed. On the other hand, one false-positive result was observed among 44 DENV-positive sera tested for COVID-19 antibodies with each of the two rapid tests used. Further data on accuracy of COVID-19 diagnostic test are urgently warranted.


Assuntos
Anticorpos Antivirais/imunologia , Infecções por Coronavirus/imunologia , Reações Cruzadas , Dengue/imunologia , Pneumonia Viral/imunologia , Betacoronavirus/imunologia , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Pandemias
14.
Sci Immunol ; 5(49)2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727884

RESUMO

Limited data are available for pregnant women affected by SARS-CoV-2. Serological tests are critically important for determining SARS-CoV-2 exposures within both individuals and populations. We validated a SARS-CoV-2 spike receptor binding domain serological test using 834 pre-pandemic samples and 31 samples from COVID-19 recovered donors. We then completed SARS-CoV-2 serological testing of 1,293 parturient women at two centers in Philadelphia from April 4 to June 3, 2020. We found 80/1,293 (6.2%) of parturient women possessed IgG and/or IgM SARS-CoV-2-specific antibodies. We found race/ethnicity differences in seroprevalence rates, with higher rates in Black/non-Hispanic and Hispanic/Latino women. Of the 72 seropositive women who also received nasopharyngeal polymerase chain reaction testing during pregnancy, 46 (64%) were positive. Continued serologic surveillance among pregnant women may inform perinatal clinical practices and can potentially be used to estimate exposure to SARS-CoV-2 within the community.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Disparidades nos Níveis de Saúde , Pneumonia Viral/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adulto , Afro-Americanos/estatística & dados numéricos , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/estatística & dados numéricos , Estudos de Coortes , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Feminino , Hispano-Americanos/estatística & dados numéricos , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Pandemias , Philadelphia/epidemiologia , Pneumonia Viral/sangue , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Gravidez , Complicações Infecciosas na Gravidez/sangue , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/virologia , Domínios Proteicos/imunologia , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
15.
Nat Commun ; 11(1): 3730, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32709840

RESUMO

Long-term follow up studies from Ebola virus disease (EVD) survivors (EBOV_S) are lacking. Here, we evaluate immune and gene expression profiles in 35 Guinean EBOV_S from the last West African outbreak, a median of 23 months (IQR [18-25]) after discharge from treatment center. Compared with healthy donors, EBOV_S exhibit increases of blood markers of inflammation, intestinal tissue damage, T cell and B cell activation and a depletion of circulating dendritic cells. All survivors have EBOV-specific IgG antibodies and robust and polyfunctional EBOV-specific memory T-cell responses. Deep sequencing of the genes expressed in blood reveals an enrichment in 'inflammation' and 'antiviral' pathways. Integrated analyses identify specific immune markers associated with the persistence of clinical symptoms. This study identifies a set of biological and genetic markers that could be used to define a signature of "chronic Ebola virus disease (CEVD)".


Assuntos
Ebolavirus/imunologia , Doença pelo Vírus Ebola/complicações , Doença pelo Vírus Ebola/imunologia , Doenças do Sistema Imunitário/complicações , Doenças do Sistema Imunitário/imunologia , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antivirais/farmacologia , Linfócitos B/imunologia , Citocinas/sangue , Ebolavirus/efeitos dos fármacos , Ebolavirus/genética , Feminino , Marcadores Genéticos , Doença pelo Vírus Ebola/tratamento farmacológico , Doença pelo Vírus Ebola/virologia , Humanos , Doenças do Sistema Imunitário/genética , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Inflamação/genética , Ativação Linfocitária , Masculino , Sobreviventes , Linfócitos T/imunologia , Transcriptoma , Adulto Jovem
17.
J Infect Dis ; 222(8): 1265-1269, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32726417

RESUMO

We determined and compared the humoral immune response in patients with severe (hospitalized) and mild (nonhospitalized) coronavirus disease 2019 (COVID-19). Patients with severe disease (n = 38) develop a robust antibody response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including immunoglobulin G and immunoglobulin A antibodies. The geometric mean 50% virus neutralization titer is 1:240. SARS-CoV-2 infection was found in hospital personnel (n = 24), who developed mild symptoms necessitating leave of absence and self-isolation, but not hospitalization; 75% developed antibodies, but with low/absent virus neutralization (60% with titers <1:20). While severe COVID-19 patients develop a strong antibody response, mild SARS-CoV-2 infections induce a modest antibody response. Long-term monitoring will show whether these responses predict protection against future infections.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Anticorpos Antivirais/sangue , Formação de Anticorpos , Betacoronavirus/isolamento & purificação , Estudos de Coortes , Infecções por Coronavirus/sangue , Infecções por Coronavirus/virologia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Testes de Neutralização , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/virologia , Índice de Gravidade de Doença
18.
J Korean Med Sci ; 35(29): e269, 2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32715672

RESUMO

BACKGROUND: Seroprevalence studies of coronavirus disease 2019 (COVID-19) from many countries have shown that the number of undiagnosed missing cases is much larger than that of confirmed cases, irrespective of seroprevalence levels. Considering the strategy of Korea entailing massive testing and contact tracing from the beginning of epidemic, the number of undiagnosed missing cases in Korea may be negligible. This study was conducted to estimate the seroprevalence of COVID-19 among individuals who were never diagnosed with COVID-19 in Daegu, the epicenter of COVID-19 epidemic in Korea. METHODS: Serologic testing for immunoglobulin G antibody based on immunochromatographic assay was conducted in 103 patients and 95 guardians aged 18 to 82 years without any history of COVID-19 diagnosis, who visited outpatient clinics of a single university-affiliated hospital from May 25 to June 5, 2020. RESULTS: The estimated seroprevalence was 7.6% (95% confidence interval, 4.3%-12.2%) with 15 positive cases. Among them, only one had a polymerase chain reaction (PCR)-confirmed case among their close contacts and 13 did not experience COVID-19-related symptoms. Seroprevalence was similar between patients and guardians. Based on this figure, the number of undiagnosed missing cases in Daegu was estimated to be a dozen times more than the number of confirmed cases based on PCR testing. CONCLUSION: Despite the limitation of a small and unrepresentative sample, this is the first study on seroprevalence of COVID-19 in Korea. Our study suggested that the number of undiagnosed missing cases was substantial even with the stringent strategy adopted in Korea, similar to that of other countries.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Coronavirus/epidemiologia , Imunoglobulina G/sangue , Pneumonia Viral/epidemiologia , Estudos Soroepidemiológicos , Doenças não Diagnosticadas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Instituições de Assistência Ambulatorial , Betacoronavirus/imunologia , Busca de Comunicante , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase , República da Coreia/epidemiologia , Testes Sorológicos , Inquéritos e Questionários , Doenças não Diagnosticadas/virologia , Adulto Jovem
19.
Eur J Clin Invest ; 50(10): e13357, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32691863

RESUMO

AIMS: To validate the diagnostic accuracy of the Augurix SARS-CoV-2 IgM/IgG rapid immunoassay diagnostic test (RDT) for COVID-19. METHODS: In this unmatched 1:1 case-control study, blood samples from 46 real-time RT-PCR-confirmed SARS-CoV-2 hospitalized cases and 45 healthy donors (negative controls) were studied. Diagnostic accuracy of the IgG RDT was assessed against both an in-house recombinant spike-expressing immunofluorescence assay (rIFA), as an established reference method (primary endpoint), and the Euroimmun SARS-CoV-2 IgG enzyme-linked immunosorbent assays (ELISA) (secondary endpoint). RESULTS: COVID-19 patients were more likely to be male (61% vs 20%; P = .0001) and older (median 66 vs 47 years old; P < .001) than controls. Whole blood IgG-RDT results showed 86% and 93% overall Kendall concordance with rIFA and IgG ELISA, respectively. IgG RDT performances were similar between plasma and whole blood. Overall, RDT sensitivity was 88% (95% confidence interval [95%CI]: 70-96), specificity 98% (95%CI: 90-100), PPV 97% (95%CI: 80-100) and NPV 94% (95%CI: 84-98). The IgG-RDT carried out from 0 to 6 days, 7 to 14 days and > 14 days after the SARS-CoV-2 RT-PCR test displayed 30%, 73% and 100% positivity rates in the COVID-19 group, respectively. When considering samples taken >14 days after RT-PCR diagnosis, NPV was 100% (95%CI:90-100), and PPV was 100% (95%CI:72-100). CONCLUSIONS: The Augurix IgG-RDT done in whole blood displays a high diagnostic accuracy for SARS-CoV-2 IgG in high COVID-19 prevalence settings, where its use could be considered in the absence of routine diagnostic serology facilities.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Testes Sorológicos , Glicoproteína da Espícula de Coronavírus/imunologia , Idoso , Estudos de Casos e Controles , Técnicas de Laboratório Clínico , Feminino , Imunofluorescência , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , Pandemias , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade
20.
Clin Chem Lab Med ; 58(9): 1601-1607, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32609640

RESUMO

Objectives: The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread globally. The laboratory diagnosis of SARS-CoV-2 infection has relied on nucleic acid testing; however, it has some limitations, such as low throughput and high rates of false negatives. Tests of higher sensitivity are needed to effectively identify infected patients. Methods: This study has developed fully automated chemiluminescent immunoassays to determine IgM and IgG antibodies to SARS-CoV-2 in human serum. The assay performance has been evaluated at 10 hospitals. Clinical specificity was evaluated by measuring 972 hospitalized patients and 586 donors of a normal population. Clinical sensitivity was assessed on 513 confirmed cases of SARS-CoV-2 by RT-PCR. Results: The assays demonstrated satisfied assay precision with coefficient of variation of less than 4.45%. Inactivation of specimen did not affect assay measurement. SARS-CoV-2 IgM showed clinical specificity of 97.33 and 99.49% for hospitalized patients and the normal population respectively, and SARS-CoV-2 IgG showed clinical specificity of 97.43 and 99.15% respectively. SARS-CoV-2 IgM showed clinical sensitivity of 82.54, 92.93, and 84.62% before 7 days, 7-14 days, and after 14 days respectively, since onset of symptoms, and SARS-CoV-2 IgG showed clinical sensitivity of 80.95, 97.98, and 99.15% respectively at the same time points above. Conclusions: We have developed fully automated immunoassays for detecting SARS-CoV-2 IgM and IgG antibodies in human serum. The assays demonstrated high clinical specificity and sensitivity, and add great value to nucleic acid testing in fighting against the global pandemic of the SARS-CoV-2 infection.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Imunoensaio/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Pneumonia Viral/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Criança , Pré-Escolar , Técnicas de Laboratório Clínico , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Lactente , Pessoa de Meia-Idade , Pandemias , Sensibilidade e Especificidade , Adulto Jovem
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