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Oxid Med Cell Longev ; 2022: 5397733, 2022.
Article Dans Anglais | MEDLINE | ID: covidwho-1635531


The infection of coronavirus disease (COVID-19) seriously threatens human life. It is urgent to generate effective and safe specific antibodies (Abs) against the pathogenic elements of COVID-19. Mice were immunized with SARS-CoV-2 spike protein antigens: S ectodomain-1 (CoV, in short) mixed in Alum adjuvant for 2 times and boosted with CoV weekly for 6 times. A portion of mice were treated with Maotai liquor (MTL, in short) or/and heat stress (HS) together with CoV boosting. We observed that the anti-CoV Ab was successfully induced in mice that received the CoV/Alum immunization for 2 times. However, upon boosting with CoV, the CoV Ab production diminished progressively; spleen CoV Ab-producing plasma cell counts reduced, in which substantial CoV-specific Ab-producing plasma cells (sPC) were apoptotic. Apparent oxidative stress signs were observed in sPCs; the results were reproduced by exposing sPCs to CoV in the culture. The presence of MTL or/and HS prevented the CoV-induced oxidative stress in sPCs and promoted and stabilized the CoV Ab production in mice in re-exposure to CoV. In summary, CoV/Alum immunization can successfully induce CoV Ab production in mice that declines upon reexposure to CoV. Concurrent administration of MTL/HS stabilizes and promotes the CoV Ab production in mice.

Anticorps neutralisants/biosynthèse , Anticorps antiviraux/biosynthèse , Apoptose , COVID-19/immunologie , Plasmocytes/immunologie , SARS-CoV-2/physiologie , Superoxide dismutase-1/physiologie , Adjuvants immunologiques , Boissons alcooliques , Alun , Angiotensin-converting enzyme 2/physiologie , Animaux , Anticorps neutralisants/sang , Anticorps antiviraux/sang , COVID-19/enzymologie , Vaccins contre la COVID-19/immunologie , Réaction de choc thermique , Rappel de vaccin , Immunogénicité des vaccins , Kinase Janus-2/physiologie , Mâle , Souris , Souris de lignée C57BL , Stress oxydatif , Plasmocytes/effets des médicaments et des substances chimiques , Plasmocytes/anatomopathologie , Espèces réactives de l'oxygène/métabolisme , Facteur de transcription STAT-1/physiologie , Transduction du signal , Organismes exempts d'organismes pathogènes spécifiques , Glycoprotéine de spicule des coronavirus/immunologie , Vaccination
FEBS Lett ; 595(13): 1819-1824, 2021 07.
Article Dans Anglais | MEDLINE | ID: covidwho-1220171


We previously observed enhanced immunoglobulin A (IgA) responses in severe COVID-19, which might confer damaging effects. Given the important role of IgA in immune and inflammatory responses, the aim of this study was to investigate the dynamic response of the IgA isotype switch factor TGF-ß1 in COVID-19 patients. We observed, in a total of 153 COVID-19 patients, that the serum levels of TGF-ß1 were increased significantly at the early and middle stages of COVID-19, and correlated with the levels of SARS-CoV-2-specific IgA, as well as with the APACHE II score in patients with severe disease. In view of the genetic association of the TGF-ß1 activator THBS3 with severe COVID-19 identified by the COVID-19 Host Genetics Initiative, this study suggests TGF-ß1 may play a key role in COVID-19.

COVID-19/immunologie , Immunoglobuline A/sang , SARS-CoV-2/immunologie , Thrombospondines/génétique , Facteur de croissance transformant bêta-1/sang , Indice APACHE , Adulte , Sujet âgé , Anticorps antiviraux/sang , COVID-19/sang , COVID-19/génétique , Femelle , Humains , Immunoglobuline A/métabolisme , Mâle , Adulte d'âge moyen , Polymorphisme de nucléotide simple
J Med Virol ; 93(5): 3257-3260, 2021 05.
Article Dans Anglais | MEDLINE | ID: covidwho-1196531


Previous studies have revealed a diagnostic role of pathogen-specific IgA in respiratory infections. However, co-detection of serum specific IgA for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and common respiratory pathogens remains largely unexplored. This study utilizes a protein microarray technology for simultaneous and quantitative measurements of specific IgAs for eight different respiratory pathogens including adenovirus, respiratory syncytial virus, influenza virus type A, influenza virus type B, parainfluenza virus, mycoplasma pneumoniae, chlamydia pneumoniae, and SARS-CoV-2 in serum sample of patients with coronavirus disease 2019 (COVID-19). A total of 42 patients with COVID-19 were included and categorized into severe cases (20 cases) and nonsevere cases (22 cases). The results showed that co-detection rate of specific-IgA for SARS-CoV-2 with at least one pathogen were significantly higher in severe cases than that of nonsevere cases (72.2% vs. 46.2%, p = .014). Our study indicates that co-detection of IgA antibodies for respiratory pathogens might provide diagnostic value for the clinics and also be informative for risk stratification and disease management in patients with COVID-19.

Anticorps antiviraux/sang , COVID-19/immunologie , Immunoglobuline A/sang , SARS-CoV-2/immunologie , Adulte , Spécificité des anticorps , COVID-19/anatomopathologie , Femelle , Humains , Mâle , Adulte d'âge moyen
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