Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The antigenic structure of transmissible gastroenteritis (TGE) virus E2 glycoprotein has been defined at three levels: antigenic sites, antigenic subsites and epitopes. Four antigenic sites (A, B, C and D) were defined by competitive radioimmunoassay (RIA) using monoclonal antibodies (MAbs) selected from 9 fusions. About 20% (197) of the hybridomas specific for TGE virus produced neutralizing MAbs specific for site A, which was one of the antigenically dominant determinants. Site A was differentiated in three antigenic subsites: a, b and c, by characterization of 11 MAb resistant (mar) mutants, that were defined by 8, 3, and 3 MAbs, respectively. These subsites were further subdivided in epitopes. A total of 11 epitopes were defined in E2 glycoprotein, eight of which were critical for virus neutralization. Neutralizing MAbs were obtained only when native virus was used to immunize mice, although to produce hybridomas mice immunizations were made with antigen in the native, denatured, or mixtures of native and denatured form. All neutralizing MAbs reacted to conformational epitopes. The antigenic structure of the E2-glycoprotein has been defined with murine MAbs, but the antigenic sites were relevant in the swine, the natural host of the virus, because porcine sera reacted against these sites. MAbs specific for TGE virus site C reacted to non-immune porcine sera. This reactivity was not directed against porcine immunoglobulins. These results indicated that TGE virus contains epitope(s) also present in some non-immunoglobulin component of porcine serum.
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PMID:Antigenic structure of the E2 glycoprotein from transmissible gastroenteritis coronavirus. 245 77

An enzyme-linked immunosorbent assay (ELISA) based on peplomer glycoprotein E2 was developed for the detection of antibodies to transmissible gastroenteritis virus (TGEV). Purified preparations of E2 were isolated by solubilization of the viral membrane with nonion detergent Nonidet P-40, followed by sucrose density gradient sedimentation. ELISA optical density values with E2 antigen significantly exceeded the indices when other TGEV protein or intact virion antigen was used. It was shown that a virus protein concentration in the E2 preparation of 500 ng per well is sufficient to sensitize the solid phase of microplates. A comparison of the ELISA and the virus neutralization test for the detection of TGEV antibodies was conducted. A significant correlation between the ELISA and the virus neutralization test was shown (r = 0.97). This serological test may be successfully used for various immunologic investigations.
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PMID:Isolation of peplomer glycoprotein E2 of transmissible gastroenteritis virus and application in enzyme-linked immunosorbent assay. 254 96

The potential of anti-idiotypic antibodies (anti-ids) as immunogens against transmissible gastroenteritis virus (TGEV) was tested in a heterologous system. A month-old pig was immunized with a neutralizing murine monoclonal antibody (MAb, 5A5) of the IgG2a isotype, specific for the E2 glycoprotein of TGEV. The anti-ids were isolated from the serum of the immunized pig by affinity chromatography, initially on a 5A5-Sepharose column, followed by repeated adsorption on a mouse IgG2a column. The swine anti-ids thus obtained bound to the MAb 5A5 (the idiotype), but not to MAbs of the same isotype IgG2a but of different idiotypes. The anti-ids also inhibited the binding of 5A5 to TGEV in a concentration-dependent manner. Mice immunized with the anti-ids produced antibodies to TGEV. These antibodies, neutralized TGEV in vitro and inhibited the binding of 5A5 to TGEV.
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PMID:Induction of neutralizing antibodies to transmissible gastroenteritis virus by anti-idiotypic antibodies. 255 23

Two different methods were used to prepare subunit components of transmissible gastroenteritis (TGE) virus. The ultrastructure of the peplomer glycoprotein E2 of TGE virus was studied. The presence of detergent NP-40 was shown to prevent the formation of this glycoprotein aggregates. In dialysed preparations, the peplomers are aggregated to form multimer structures, the so-called "rosettes". The orientation of the peplomers in the "rosettes" and in the whole virion was identical. The antigenic activity of viral subunits was studied in guinea pigs. Preparations of isolated peplomers were shown to induce enhanced production of virus-neutralizing antibodies whose mean titre exceeded that in the group of animals immunized with whole virion-based preparations.
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PMID:[Subunit components of transmissive gastroenteritis virus of swine: preparing purified substances and assessing antigenic properties]. 255 85

Epithelial cells infected with the coronavirus transmissible gastroenteritis virus (TGEV) and fixed by glutaraldehyde induced a high alpha interferon (IFN-alpha) production in nonimmune porcine as well as human or bovine peripheral blood mononuclear cells (PBMC). IFN-alpha was detected as early as 3 h after exposure of PBMC to infected cells and at producer/inducer cell ratios as low as 1/1. Two of four monoclonal antibodies directed against the viral transmembrane glycoprotein E1 could block the IFN-inducing capacity of both TGEV-infected cells and viral particles. On the other hand, IFN-alpha induction was not markedly affected by monoclonal antibodies directed against other E1 epitopes, against peplomer glycoprotein E2, or against nucleocapsid protein. Thus, these findings strongly imply that IFN induction by TGEV results from interactions between an outer membrane domain of E1 and the PBMC membrane.
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PMID:Induction of alpha interferon by transmissible gastroenteritis coronavirus: role of transmembrane glycoprotein E1. 282 58

Two distinct subtypes of human rotavirus serotype 4 were identified by using neutralizing monoclonal antibodies directed to the major outer capsid glycoprotein, VP7, of strains ST3 (subtype 4A) and VA70 (subtype 4B). Specimens containing serotype 4 rotavirus, obtained from different countries, were examined for subtyping by using solid-phase immune electron microscopy, enzyme-linked immunosorbent assay, and, for cell culture-adapted strains, neutralization assay. All 59 human rotavirus strains identified as serotype 4 by using animal antisera were classified into either subtype by monoclonal antibodies. This suggests that the antigenic difference between the two subtypes is a consequence of critical variations within the immunodominant serotype 4-specific neutralization site of rotavirus VP7. Subtype 4A (ST3-like) strains were predominant and were detected in stools from patients with gastroenteritis, as well as from healthy infants and young children.
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PMID:Identification of two subtypes of serotype 4 human rotavirus by using VP7-specific neutralizing monoclonal antibodies. 284 73

We investigated the interactions of rotaviruses with glycoproteins and cells that support rotaviral replication. We found that a wide range of naturally occurring glycoproteins, including ovalbumins and ovomucoids from chicken and turkey eggs, and mucin derived from bovine submaxillary glands, inhibit the replication of rotaviruses in MA-104 cells. Our studies further indicated that the glycoproteins bind directly to rotaviruses and that virus-glycoprotein binding is dependent largely upon interactions with sialic acid oligosaccharides. We found that accessible sialic acid oligosaccharides are required for efficient rotavirus infection of MA-104 cells, thus demonstrating that sialic acid oligosaccharides play an important role in the interactions of rotaviruses with both glycoproteins and cells that support rotaviral replication. Bovine submaxillary mucin and chicken ovoinhibitor can also prevent the shedding of rotavirus antigen and the development of rotavirus gastroenteritis in a mouse model of rotavirus infection. Our findings document that a range of glycoproteins inhibit the in vivo and in vitro replication of rotaviruses and suggest that the alteration in the quantity or chemical composition of intestinal glycoproteins is a potential means for the modulation of enteric infections.
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PMID:Sialic acid glycoproteins inhibit in vitro and in vivo replication of rotaviruses. 302 57

The complete nucleotide sequence of cloned cDNAs containing the E2 glycoprotein-encoding region of the genome of transmissible gastroenteritis virus (TGEV) has been determined. A single large translatable frame of 4.3 kb starting at 8.2 kb from the 3' end of the genome was identified. Its deduced amino acid sequence contains the characteristic features of a coronavirus peplomer protein: the precursor polypeptide of TGEV E2 is 1447 residues long (i.e. 285 longer than the avian infectious bronchitis coronavirus spike protein); partial N-terminal sequencing demonstrated that a putative secretory signal sequence of 16 amino acids is absent in the virion-associated protein; the predicted mol. wt. of the apoprotein is 158K; most of the 32 potential N-glycosylation sites available in the sequence are presumed to be functional to account for the difference between this and the experimentally determined value (200K to 220K); a typical hydrophobic sequence near the C terminus is likely to be responsible for anchoring the peplomer to the virion envelope.
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PMID:The predicted primary structure of the peplomer protein E2 of the porcine coronavirus transmissible gastroenteritis virus. 303 11

During a search for established cell lines to produce large quantities of porcine transmissible gastroenteritis virus (TGEV), we observed bright immunofluorescent staining 6- 12h after infection of pig kidney derived LLC-PK1 line. Infectious virus yield was, however, 2 log10 lower than that from secondary adult pig thyroid (APT/2) cell cultures, although small plaques were visible by three days in cultures maintained under agarose, suggesting limited replication. Attempts to adapt TGEV to the LLC-PK1 cell line by 10 serial 20h passes were unsuccessful. Procedures to purify virions from infected LLC-PK1 cells produced less than 1% of the particles isolated from parallel APT/2 cultures. Examination of intracellular viral RNA in actinomycin-D treated cells revealed similar amounts of genomic RNA and the 4 major subgenomic species in both cell types, suggesting that there was no defect in viral RNA replication. In vitro translation of polyadenylated RNA from infected APT/2 and LLC-PK1 cells, followed by immune precipitation of the products, showed similar profiles of precursors to structural polypeptides, confirming the functional integrity of the viral messengers in the restrictive cell. Comparison of the viral polypeptides synthesised following infection of the two cell types showed that similar species were synthesised in both, corresponding to a group of 28-30,000 mol. wt. envelope glycopolypeptides, a 47,000 mol. wt. nucleoprotein and peplomer glycopolypeptides of about 200,000 mol. wt. The rate of viral polypeptide synthesis in LLC-PK1 cells was reproducibly higher than in APT/2, resulting in the earlier detection of bands and greater incorporation of isotope. Tunicamycin at 1 microgram/ml had a similar effect in both cells, preventing glycosylation of the 26,000 mol. wt. precursor of the envelope glycopolypeptides and synthesis of the 200,000 peplomer glycoprotein. Degradation of the nucleoprotein from 47,000 to 42,000 mol. wt. although detectable in both cells was more marked in the LLC-PK1 cultures. Phosphorylation of these proteins was readily demonstrated in both cells, although phosphorylation of host proteins and, to some extent, viral envelope proteins was considerably greater in the LLC-PK1. The significance of this finding with respect to virus maturation is being investigated.
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PMID:Defective replication of porcine transmissible gastroenteritis virus in a continuous cell line. 633 Nov 29

Jejunal biopsies from 20 well nourished children (average age 12.8 months) with gastroenteritis, and 20 children (average age 20 months) with protein-energy malnutrition were examined by immunofluorescent technique for immunoglobulins A, G, M, E, and D, and for epithelial glycoprotein secretory component. Compared with previous studies on normal infants, the children with gastroenteritis showed a moderate increase in IgA-containing cells, a large increase in IgM-containing cells, and no change in IgG-containing cells. These findings are similar to previously recorded findings on adults with gastroenteritis. In contrast there was a pronounced and highly significant decrease in IgA-containing cells in the jejunal mucosa of the children with protein-energy malnutrition. No significant differences were noted between the populations of IgG-, IgM-, IgE-, and IgD-containing cells in the two groups. It is suggested that this selective deficiency in mucosal IgA results from a delay in maturation of the secretory IgA system, and the mechanisms of such a deficiency are discussed.
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PMID:Immunoglobulin-containing cells in jejunal mucosa of children with protein-energy malnutrition and gastroenteritis. 677 3


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