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
• Názvy látek
• imunoglobulin A sekreční MeSH
• imunoglobuliny - Fab fragmenty MeSH
• jednořetězcové protilátky MeSH
• polysacharidy MeSH

The effect of controlled antigenic stimulation in immunologically virgin organisms, i.e. pig fetuses treated with NDCM (Nocardia delipidated cell mitogen) and germ-free (GF) piglets associated with a non-pathogenic E. coli 086, on peripheral blood lymphocyte subsets defined by the expression of CD5 and CD8 was studied by double color flow cytometry. Stimulation of both fetuses and GF piglets increased the frequency of CD8low+ lymphocytes. A prominent subset of CD5-CD8low+NK cells was present in GF and E. coli associated piglets and their frequency was slightly higher in E. coli associated animals. The most pronounced difference between stimulated and non-stimulated animals was in a relative proportion of an ill-defined lymphocyte subset with an unusual CD5low+CD8low+ expression. Both NDCM injection into fetal blood circulation and association of GF piglets with E. coli resulted in a marked increase of frequency of CD5low+CD8low+ lymphocytes in peripheral blood.

• MeSH
• adjuvancia imunologická * MeSH
• aktivace lymfocytů * MeSH
• antigeny CD5 analýza   MeSH
• antigeny CD8 analýza   MeSH
• Escherichia coli imunologie   MeSH
• gnotobiologické modely MeSH
• imunizace * MeSH
• imunofenotypizace MeSH
• plod MeSH
• podskupiny lymfocytů imunologie   MeSH
• prasata MeSH
• průtoková cytometrie MeSH
• těhotenství MeSH
• zvířata MeSH
• Check Tag
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adjuvancia imunologická * MeSH
• antigeny CD5 MeSH
• antigeny CD8 MeSH

Pig fetuses, colostrum-deprived newborns and germ-free (GF) piglets, animals in which B-cell development is not influenced by maternal regulatory factors, were employed to study the occurrence and specificity of natural antibodies (NAb). Serum immunoglobulins of all isotypes were found in 44-day-old fetuses (the gestation period in pigs lasts 114 days) and their level, with predominating IgM, was increased during fetal ontogeny. In sera of fetuses at the end of embryonic life as well as of newborns and older GF piglets, antibody activity against autoantigens (thyroglobulin, hormones, ssDNA), phylogenetically conserved proteins (myosin), haptens (trinitrophenyl; TNP) and bacterial components (Escherichia coli O86, tetanic anatoxin) was detected by enzyme-linked immunosorbent assay. The antigen-biding activity of IgM NAb increased after isolation of the serum immunoglobulins on a Staphylococcus Protein A (SPA)-Sepharose column. IgM reactivity similar to that detected in serum was found in supernatants from polyclonally stimulated cultures of spleen of 8- and 12-day-old GF piglets. Pig fetal liver IgM+ B cells, which were able to produce IgM after polyclonal stimulation, did not express the CD5 molecule. Our results indicate that pig preimmune repertoire is comparable to that described in humans and mice, although in contrast to these species pig B-1 cells do not express CD5.

• MeSH
• antigeny CD5 analýza   MeSH
• B-lymfocyty imunologie   MeSH
• buněčné kultury MeSH
• gnotobiologické modely MeSH
• imunoglobulin M biosyntéza   MeSH
• imunoglobulinové izotypy krev   MeSH
• imunoglobuliny biosyntéza   MeSH
• játra embryologie   imunologie   MeSH
• novorozená zvířata MeSH
• plod imunologie   MeSH
• prasata imunologie   MeSH
• specificita protilátek MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD5 MeSH
• imunoglobulin M MeSH
• imunoglobulinové izotypy MeSH
• imunoglobuliny MeSH

The aim of this study was to investigate spontaneous immunoglobulin production and a pattern of isotype switching by thymic B lymphocytes (TBL) as compared with cells isolated from spleen during early ontogeny using a pig model in which B-cell development is not influenced by maternal regulatory factors. A sensitive ELISPOT assay was therefore employed to detect immunoglobulins in pig fetuses, colostrum-deprived germ-free (GF) piglets as well as conventionally (CONV) reared pigs. The first spontaneously immunoglobulin-secreting cells in the thymus were detected in 67-day-old fetuses (the length of gestation period in pigs is 114 days), their number increasing during fetal ontogeny. In contrast to fetal splenic cells, which secrete exclusively IgM, fetal thymic immunoglobulin-secreting cells were determined to undergo spontaneous isotype switching to IgG and IgA. In 28-day-old GF piglets and 3-month-old CONV pigs the number of thymic immunoglobulin-secreting cells of all isotypes was comparable to the number of thymic immunoglobulin-secreting cells detected in the newborn thymus. Considerable augmentation of IgG and IgA production by splenic immunoglobulin-secreting cells in CONV pigs was observed as compared to GF newborns and GF piglets, in which IgG- and IgA-secreting cells were detected occasionally. Our results indicate that TBL represent the first B-cell population in early fetal ontogeny spontaneously undergoing isotype switching to IgG and IgA; in the postnatal period the TBL population does not appear to be influenced by external antigenic stimuli of conventional microflora.

• MeSH
• B-lymfocyty imunologie   MeSH
• ELISA MeSH
• gestační stáří MeSH
• gnotobiologické modely * MeSH
• imunoglobulin A biosyntéza   MeSH
• imunoglobulin G biosyntéza   MeSH
• imunoglobulin M biosyntéza   MeSH
• imunoglobulinové izotypy biosyntéza   MeSH
• miniaturní prasata embryologie   růst a vývoj   imunologie   MeSH
• prasata MeSH
• přesmyk imunoglobulinových tříd MeSH
• slezina růst a vývoj   imunologie   MeSH
• thymus embryologie   růst a vývoj   imunologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• imunoglobulin A MeSH
• imunoglobulin G MeSH
• imunoglobulin M MeSH
• imunoglobulinové izotypy MeSH