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1.
Sci Rep ; 13(1): 14165, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37644113

RESUMO

The humoral response after the fourth dose of a mRNA vaccine against COVID-19 has not been adequately described in elderly recipients, particularly those not exposed previously to SARS-CoV-2. Serum anti-RBD IgG levels (Abbott SARS-CoV-2 IgG II Quant assay) and neutralizing capacities (spike SARS-CoV-2 pseudovirus Wuhan and Omicron BA.1 variant) were measured after the third and fourth doses of a COVID-19 mRNA vaccine among 46 elderly residents (median age 85 years [IQR 81; 89]) of an assisted living facility. Among participants never infected by SARS-CoV-2, the mean serum IgG levels against RBD (2025 BAU/ml), 99 days after the fourth vaccine, was as high as 76 days after the third vaccine (1987 BAU/ml), and significantly higher (p = 0.030) when the latter were corrected for elapsed time. Neutralizing antibody levels against the historical Wuhan strain were significantly higher (Mean 1046 vs 1573; p = 0.002) and broader (against Omicron) (Mean 170 vs 375; p = 0.018), following the fourth vaccine. The six individuals with an Omicron breakthrough infection mounted strong immune responses for anti-RBD and neutralizing antibodies against the Omicron variant indicating that the fourth vaccine dose did not prevent a specific adaptation of the immune response. These findings point out the value of continued vaccine boosting in the elderly population.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Idoso , Idoso de 80 Anos ou mais , Formação de Anticorpos , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Neutralizantes , Imunoglobulina G , RNA Mensageiro
2.
Front Immunol ; 13: 933347, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36798518

RESUMO

Intramuscularly administered vaccines stimulate robust serum neutralizing antibodies, yet they are often less competent in eliciting sustainable "sterilizing immunity" at the mucosal level. Our study uncovers a strong temporary neutralizing mucosal component of immunity, emanating from intramuscular administration of an mRNA vaccine. We show that saliva of BNT162b2 vaccinees contains temporary IgA targeting the receptor-binding domain (RBD) of severe acute respiratory syndrome coronavirus-2 spike protein and demonstrate that these IgAs mediate neutralization. RBD-targeting IgAs were found to associate with the secretory component, indicating their bona fide transcytotic origin and their polymeric multivalent nature. The mechanistic understanding of the high neutralizing activity provided by mucosal IgA, acting at the first line of defense, will advance vaccination design and surveillance principles and may point to novel treatment approaches and new routes of vaccine administration and boosting.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , RNA Mensageiro , Imunoglobulina A
3.
Proc Natl Acad Sci U S A ; 118(34)2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34373319

RESUMO

Atomic structures of several proteins from the coronavirus family are still partial or unavailable. A possible reason for this gap is the instability of these proteins outside of the cellular context, thereby prompting the use of in-cell approaches. In situ cross-linking and mass spectrometry (in situ CLMS) can provide information on the structures of such proteins as they occur in the intact cell. Here, we applied targeted in situ CLMS to structurally probe Nsp1, Nsp2, and nucleocapsid (N) proteins from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and obtained cross-link sets with an average density of one cross-link per 20 residues. We then employed integrative modeling that computationally combined the cross-linking data with domain structures to determine full-length atomic models. For the Nsp2, the cross-links report on a complex topology with long-range interactions. Integrative modeling with structural prediction of individual domains by the AlphaFold2 system allowed us to generate a single consistent all-atom model of the full-length Nsp2. The model reveals three putative metal binding sites and suggests a role for Nsp2 in zinc regulation within the replication-transcription complex. For the N protein, we identified multiple intra- and interdomain cross-links. Our integrative model of the N dimer demonstrates that it can accommodate three single RNA strands simultaneously, both stereochemically and electrostatically. For the Nsp1, cross-links with the 40S ribosome were highly consistent with recent cryogenic electron microscopy structures. These results highlight the importance of cellular context for the structural probing of recalcitrant proteins and demonstrate the effectiveness of targeted in situ CLMS and integrative modeling.


Assuntos
Modelos Moleculares , SARS-CoV-2/química , Proteínas Virais/química , Reagentes de Ligações Cruzadas/química , Células HEK293 , Humanos , Espectrometria de Massas , Domínios Proteicos
4.
Birth ; 39(2): 121-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23281860

RESUMO

BACKGROUND: Listening to music has a stress-reducing effect in surgical procedures. The effects of listening to music immediately before a cesarean section have not been studied. The objective of this study was to assess the effects of listening to selected music while waiting for a cesarean section on emotional reactions, on cognitive appraisal of the threat of surgery, and on stress-related physiological reactions. METHODS: A total of 60 healthy women waiting alone to undergo an elective cesarean section for medical reasons only were randomly assigned either to an experimental or a control group. An hour before surgery they reported mood, and threat perception. Vital signs were assessed by a nurse. The experimental group listened to preselected favorite music for 40 minutes, and the control group waited for the operation without music. At the end of this period, all participants responded to a questionnaire assessing mood and threat perception, and the nurse measured vital signs. RESULTS: Women who listened to music before a cesarean section had a significant increase in positive emotions and a significant decline in negative emotions and perceived threat of the situation when compared with women in the control group, who exhibited a decline in positive emotions, an increase in the perceived threat of the situation, and had no change in negative emotions. Women who listened to music also exhibited a significant reduction in systolic blood pressure compared with a significant increase in diastolic blood pressure and respiratory rate in the control group. CONCLUSION: Listening to favorite music immediately before a cesarean section may be a cost-effective, emotion-focused coping strategy. (BIRTH 39:2 June 2012).


Assuntos
Ansiedade/prevenção & controle , Cesárea/psicologia , Comportamento Materno/psicologia , Música/psicologia , Cuidados Pré-Operatórios/psicologia , Adaptação Psicológica , Adulto , Ansiedade/psicologia , Percepção Auditiva , Cognição , Procedimentos Cirúrgicos Eletivos/psicologia , Feminino , Humanos , Gravidez , Cuidados Pré-Operatórios/métodos , Estresse Psicológico/prevenção & controle , Saúde da Mulher , Adulto Jovem
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