Secretory (S) IgA antibodies against severe acute respiratory syndrome (SARS)-CoV-2 are induced in saliva and upper respiratory tract (URT) secretions by natural infection and may be critical in determining the outcome of initial infection. Secretory IgA1 (SIgA1) is the predominant isotype of antibodies in these secretions. Neutralization of SARS-CoV-2 is most effectively accomplished by polymeric antibodies such as SIgA. We hypothesize that cleavage of SIgA1 antibodies against SARS-CoV-2 by unique bacterial IgA1 proteases to univalent Fabα antibody fragments with diminished virus neutralizing activity would facilitate the descent of the virus into the lungs to cause serious disease and also enhance its airborne transmission to others. Recent studies of the nasopharyngeal microbiota of patients with SARS-CoV-2 infection have revealed significant increases in the proportions of IgA1 protease-producing bacteria in comparison with healthy subjects. Similar considerations might apply also to other respiratory viral infections including influenza, possibly explaining the original attribution of influenza to Haemophilus influenzae, which produces IgA1 protease.
- MeSH
- Bacteria enzymologie MeSH
- COVID-19 * přenos imunologie virologie mikrobiologie MeSH
- Haemophilus influenzae enzymologie imunologie MeSH
- imunoglobulin A sekreční * metabolismus MeSH
- imunoglobulin A imunologie MeSH
- lidé MeSH
- nazofarynx mikrobiologie virologie MeSH
- neutralizující protilátky imunologie MeSH
- protilátky virové imunologie MeSH
- SARS-CoV-2 * imunologie MeSH
- serinové endopeptidasy metabolismus imunologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Mucosal surfaces are colonized by highly diverse commensal microbiota. Coating with secretory IgA (SIgA) promotes the survival of commensal bacteria while it inhibits the invasion by pathogens. Bacterial coating could be mediated by antigen-specific SIgA recognition, polyreactivity, and/or by the SIgA-associated glycans. In contrast to many in vitro studies, only a few reported the effect of SIgA glycans in vivo. Here, we used a germ-free antibody-free newborn piglets model to compare the protective effect of SIgA, SIgA with enzymatically removed N-glycans, Fab, and Fc containing the secretory component (Fc-SC) during oral necrotoxigenic E. coli O55 challenge. SIgA, Fab, and Fc-SC were protective, whereas removal of N-glycans from SIgA reduced SIgA-mediated protection as demonstrated by piglets' intestinal histology, clinical status, and survival. In vitro analyses indicated that deglycosylation of SIgA did not reduce agglutination of E. coli O55. These findings highlight the role of SIgA-associated N-glycans in protection. Further structural studies of SIgA-associated glycans would lead to the identification of those involved in the species-specific inhibition of attachment to corresponding epithelial cells.
- MeSH
- aglutinace MeSH
- Escherichia coli fyziologie MeSH
- glykosylace MeSH
- gnotobiologické modely MeSH
- imunoglobulin A sekreční metabolismus MeSH
- imunoglobuliny - Fab fragmenty metabolismus MeSH
- infekce vyvolané Escherichia coli imunologie MeSH
- jednořetězcové protilátky metabolismus MeSH
- novorozená zvířata MeSH
- odolnost vůči nemocem MeSH
- polysacharidy metabolismus MeSH
- prasata MeSH
- těhotenství MeSH
- zvířata MeSH
- Check Tag
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The aim of the study was to determine whether cortisol and secretory Immunoglobulin A (sIgA) could be used as an indicator of acute stress in both young and adult dogs. Seventeen German shepherd puppies were exposed to the Puppy test (challenge test) at the age of seven weeks. This test has been routinely used to assess the future working ability of potential police dogs. In addition, ten adult females were subjected to 4 minutes of defense training under stressful conditions. Saliva was collected from the puppies and adult females before testing and 20 minutes after the start of testing, using a cotton swab held for 1-2 minutes in each dog's mouth. Cortisol concentrations increased after the test compared to the control sample both in puppies and the adult females. However adult females showed a significant decrease in sIgA after defense training while puppies showed a tendency of increase in sIgA. We propose that salivary cortisol could be used as an indicator of stress in puppies during early ontogeny. It is not yet clear whether sIgA could be used as a useful indicator of short-term stress in dogs.
- MeSH
- anorganické látky metabolismus MeSH
- dospělí MeSH
- fyziologie výživy kojenců MeSH
- imunoglobulin A sekreční * fyziologie imunologie metabolismus MeSH
- Lactobacillus MeSH
- laktace fyziologie MeSH
- laktoferrin * fyziologie imunologie metabolismus MeSH
- lidé MeSH
- mateřské mléko * imunologie metabolismus MeSH
- muramidasa * fyziologie imunologie metabolismus MeSH
- novorozenec MeSH
- probiotika MeSH
- proteiny metabolismus MeSH
- referenční hodnoty MeSH
- sacharidy MeSH
- stopové prvky metabolismus MeSH
- střevní sliznice MeSH
- tuky metabolismus MeSH
- vitaminy metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- novorozenec MeSH
- ženské pohlaví MeSH
- MeSH
- adenokarcinom patologie MeSH
- bakteriální adheze MeSH
- bakteriální fimbrie fyziologie MeSH
- erytrocyty MeSH
- Escherichia coli * fyziologie MeSH
- hemaglutinační testy MeSH
- imunita získaná od matky MeSH
- imunoglobulin A sekreční * metabolismus MeSH
- kojení * MeSH
- kolon * mikrobiologie MeSH
- kur domácí MeSH
- lidé MeSH
- mannosa * fyziologie MeSH
- mateřské mléko * imunologie MeSH
- morčata MeSH
- nádorové buňky kultivované MeSH
- nádory tračníku patologie MeSH
- novorozenec * imunologie MeSH
- potrava pro kojence MeSH
- rektum mikrobiologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- morčata MeSH
- novorozenec * imunologie MeSH
- zvířata MeSH
- Publikační typ
- srovnávací studie MeSH
