Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
1.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-312509

ABSTRACT

Convalescent plasma (CP) is widely used to treat Covid-19, but without formal evidence of efficacy. Here, we report the beneficial effects of CP in a severely ill Covid-19 patient with prolonged pneumonia and advanced chronic lymphocytic leukemia (CLL), who was unable to generate an antiviral antibody response of her own. On day-33 after becoming symptomatic, the patient received CP containing high-titer (ID 50 >5,000) neutralizing antibodies (NAbs), defervesced and improved clinically within 48 hours, and was discharged on day-37. Hence, when present in sufficient quantities, NAbs to SARS-CoV-2 have curative potential even if administered relatively late in the disease course.

2.
Nat Commun ; 13(1): 128, 2022 01 10.
Article in English | MEDLINE | ID: covidwho-1616978

ABSTRACT

The quality and persistence of children's humoral immune response following SARS-CoV-2 infection remains largely unknown but will be crucial to guide pediatric SARS-CoV-2 vaccination programs. Here, we examine 548 children and 717 adults within 328 households with at least one member with a previous laboratory-confirmed SARS-CoV-2 infection. We assess serological response at 3-4 months and 11-12 months after infection using a bead-based multiplex immunoassay for 23 human coronavirus antigens including SARS-CoV-2 and its Variants of Concern (VOC) and endemic human coronaviruses (HCoVs), and additionally by three commercial SARS-CoV-2 antibody assays. Neutralization against wild type SARS-CoV-2 and the Delta VOC are analysed in a pseudotyped virus assay. Children, compared to adults, are five times more likely to be asymptomatic, and have higher specific antibody levels which persist longer (96.2% versus 82.9% still seropositive 11-12 months post infection). Of note, symptomatic and asymptomatic infections induce similar humoral responses in all age groups. SARS-CoV-2 infection occurs independent of HCoV serostatus. Neutralization responses of children and adults are similar, although neutralization is reduced for both against the Delta VOC. Overall, the long-term humoral immune response to SARS-CoV-2 infection in children is of longer duration than in adults even after asymptomatic infection.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , Immunity, Humoral/immunology , SARS-CoV-2/immunology , Adolescent , Adult , Antigens, Viral/immunology , COVID-19/prevention & control , COVID-19/virology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/immunology , Child , Child, Preschool , Cross Reactions/immunology , Female , Humans , Infant , Male , SARS-CoV-2/genetics , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/immunology , Vaccination/methods
3.
EBioMedicine ; 75: 103761, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1587930

ABSTRACT

BACKGROUND: Heterologous COVID-19 vaccination regimens combining vector- and mRNA-based vaccines are already administered, but data on solicited adverse reactions, immunological responses and elicited protection are limited. METHODS: To evaluate the reactogenicity and humoral as well as cellular immune responses towards most prevalent SARS-CoV-2 variants after a heterologous ChAdOx1 nCoV-19 BNT162b2 prime-boost vaccination, we analysed a cohort of 26 clinic employees aged 25-46 (median 30.5) years who received a ChAdOx1 nCoV-19 prime followed by a BNT162b2 boost after an 8-week interval. Serological data were compared to a cohort which received homologous BNT162b2 vaccination with a 3-week interval (14 individuals aged 25-65, median 42). FINDINGS: Self-reported solicited symptoms after ChAdOx1 nCoV-19 prime were in line with previous reports and more severe than after the BNT162b2 boost. Antibody titres increased significantly over time resulting in strong neutralization titres two weeks after the BNT162b2 boost and subsequently slightly decreased over the course of 17 weeks. At the latest time point measured, all analysed sera retained neutralizing activity against the currently dominant Delta (B.1.617.2) variant. Two weeks post boost, neutralizing activity against the Alpha (B.1.1.7) and immune-evading Beta (B.1.351) variant was ∼4-fold higher than in individuals receiving homologous BNT162b2 vaccination. No difference was observed in neutralization of Kappa (B.1.617.1). In addition, heterologous vaccination induced CD4+ and CD8+ T cells reactive to SARS-CoV-2 spike peptides of all analysed variants; Wuhan-Hu-1, Alpha, Beta, Gamma (P.1), and Delta. INTERPRETATION: In conclusion, heterologous ChAdOx1 nCoV-19 / BNT162b2 prime-boost vaccination is not associated with serious adverse events and induces potent humoral and cellular immune responses. The Alpha, Beta, Delta, and Kappa variants of spike are potently neutralized by sera from all participants and reactive T cells recognize spike peptides of all tested variants. These results suggest that this heterologous vaccination regimen is at least as immunogenic and protective as homologous vaccinations and also offers protection against current variants of concern. FUNDING: This project has received funding from the European Union's Horizon 2020 research and innovation programme, the German Research Foundation, the BMBF, the Robert Koch Institute (RKI), the Baden-Württemberg Stiftung, the county of Lower Saxony, the Ministry for Science, Research and the Arts of Baden-Württemberg, Germany, and the National Institutes of Health.


Subject(s)
Antibodies, Neutralizing/immunology , COVID-19/prevention & control , Immunity, Cellular/drug effects , Immunization, Secondary , SARS-CoV-2/immunology , T-Lymphocytes/immunology , Adult , COVID-19/epidemiology , COVID-19/immunology , Female , Humans , Male , Middle Aged , Prevalence
4.
Emerg Infect Dis ; 27(9): 2454-2458, 2021 09.
Article in English | MEDLINE | ID: covidwho-1435936

ABSTRACT

Not all persons recovering from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection develop SARS-CoV-2-specific antibodies. We show that nonseroconversion is associated with younger age and higher reverse transcription PCR cycle threshold values and identify SARS-CoV-2 viral loads in the nasopharynx as a major correlate of the systemic antibody response.


Subject(s)
COVID-19 , Antibody Formation , COVID-19/immunology , COVID-19 Serological Testing , Humans , Nasopharynx , SARS-CoV-2 , Seroconversion
5.
Emerg Infect Dis ; 27(9): 2454-2458, 2021 09.
Article in English | MEDLINE | ID: covidwho-1291007

ABSTRACT

Not all persons recovering from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection develop SARS-CoV-2-specific antibodies. We show that nonseroconversion is associated with younger age and higher reverse transcription PCR cycle threshold values and identify SARS-CoV-2 viral loads in the nasopharynx as a major correlate of the systemic antibody response.


Subject(s)
COVID-19 , Antibody Formation , COVID-19/immunology , COVID-19 Serological Testing , Humans , Nasopharynx , SARS-CoV-2 , Seroconversion
6.
Cell Rep Med ; 2(1): 100164, 2021 01 19.
Article in English | MEDLINE | ID: covidwho-957488

ABSTRACT

Convalescent plasma (CP) is widely used to treat COVID-19, but without formal evidence of efficacy. Here, we report the beneficial effects of CP in a severely ill COVID-19 patient with prolonged pneumonia and advanced chronic lymphocytic leukemia (CLL), who was unable to generate an antiviral antibody response of her own. On day 33 after becoming symptomatic, the patient received CP containing high-titer (ID50 > 5,000) neutralizing antibodies (NAbs), defervesced, and improved clinically within 48 h and was discharged on day 37. Hence, when present in sufficient quantities, NAbs to SARS-CoV-2 have clinical benefit even if administered relatively late in the disease course. However, analysis of additional CP units revealed widely varying NAb titers, with many recipients exhibiting endogenous NAb responses far exceeding those of the administered units. To obtain the full therapeutic benefits of CP immunotherapy, it will thus be important to determine the neutralizing activity in both CP units and transfusion candidates.


Subject(s)
COVID-19/therapy , Aged , Antibodies, Neutralizing/administration & dosage , COVID-19/complications , COVID-19/pathology , COVID-19/virology , Female , Humans , Immunization, Passive , Immunocompromised Host , Leukemia, Lymphocytic, Chronic, B-Cell/complications , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Lung/diagnostic imaging , SARS-CoV-2/isolation & purification , Severity of Illness Index , Tomography, X-Ray Computed
8.
Br J Radiol ; 93(1112): 20200243, 2020 Aug.
Article in English | MEDLINE | ID: covidwho-378118

ABSTRACT

OBJECTIVES: The chest CT findings that can distinguish patients with corona virus disease 2019 (COVID-19) from those with clinically suspected COVID-19 but subsequently found to be COVID-19 negative have not previously been described in detail. The purpose of this study was to determine the distinctions among patients with COVID-19 by comparing the imaging findings of patients with suspected confirmed COVID-19 and those of patients initially suspected to have COVID-19 who were ultimately negative for the disease. METHODS: 28 isolated suspected in-patients with COVID-19 were enrolled in this retrospective study from January 22, 2020 to February 6, 2020. 12 patients were confirmed to have positive severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) RNA results, and 16 patients had negative results. The thin-section CT imaging findings and clinical and laboratory data of all the patients were evaluated. RESULTS: There were no significant differences between the 12 confirmed COVID-19 (SARS-Cov-2-positive) patients and 16 SARS-CoV-2-negative patients in epidemiology and most of the clinical features or laboratory data. The CT images showed that the incidence of pure/mixed ground-glass opacities (GGOs) was not different between COVID-19 and SARS-CoV-2-negative patients [9/12 (75.0%) vs 10/16 (62.5%), p = 0.687], but pure/mixed GGOs in the peripheral were more common in patients with COVID-19 [11/12 (91.7%) vs 6/16 (37.5%), p = 0.006]. There were no significant differences in the number of lesions, bilateral lung involvement, large irregular/patchy opacities, rounded opacities, linear opacities, crazy-paving patterns, halo signs, interlobular septal thickening or air bronchograms. CONCLUSIONS: Although peripheral pure/mixed GGOs on CT may help distinguish patients with COVID-19 from clinically suspected but negative patients, CT cannot replace RT-PCR testing. ADVANCES IN KNOWLEDGE: Peripheral pure/mixed GGOs on-chest CT findings can be helpful in distinguishing patients with COVID-19 from those with clinically suspected COVID-19 but subsequently found to be COVID-19 negative.


Subject(s)
Coronavirus Infections/diagnostic imaging , Lung/diagnostic imaging , Pneumonia, Viral/diagnostic imaging , Tomography, X-Ray Computed , Adult , Betacoronavirus , COVID-19 , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Pandemics , RNA, Viral/analysis , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2
SELECTION OF CITATIONS
SEARCH DETAIL