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)

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

Natural killer (NK) cell activity in the peripheral blood lymphocytes (PBL) of newborn piglets, normally negligible, was stimulated by in vitro treatment with porcine type I interferon (IFN), and the NK activity of PBL from weaned piglets was augmented by the same treatment. Binding of the PBL to the PK-15 targets used in the single cell cytotoxicity assay for NK activity was not affected by age or by IFN treatment. When newborn piglets were treated with a single intravenous dose at 2 days of age of 0.5 mg/kg of polyinosinic:polycytidylic acid complexed with poly-L-lysine and carboxymethylcellulose (poly ICLC), a synthetic IFN inducer, their IFN levels peaked at 6 h post-induction, and NK activity in their PBL peaked at 24 h post-induction at the level normally found in weaned piglets. The NK activity then declined until 7 days post-induction, when it increased again in a similar manner to that in untreated control piglets. Target-binding of the PBL was not affected by poly ICLC treatment of the piglets. Newborn piglets treated with poly ICLC and subsequently exposed to infection with transmissible gastroenteritis (TGE) virus showed a delay in onset of clinical signs of TGE compared with untreated control piglets. It was concluded that NK cells in newborn piglets can be activated by treatment of the piglets with poly ICLC, and that the presence of active NK cells is associated with some increase in resistance to challenge with TGE virus.
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PMID:Activation of natural killer cells in newborn piglets by interferon induction. 283 48

Recombinant DNA-derived bovine interferon alpha 1-1 (BoIFN) inhibited replication of both vesicular stomatitis virus and transmissible gastroenteritis virus in cultures of swine testicular cells. Newborn pigs were orally inoculated with BoIFN and subsequently had interferon in their gastric contents and serum; however, interferon was found only occasionally in intestinal washings. Incubation of BoIFN with gastric contents from a newborn suckling pig did not affect antiviral activity, whereas intestinal (small intestine) contents from the same animal inactivated BoIFN within 1 minute. Beginning at 6 hours of age, newborn, colostrum-deprived pigs were given 1 mg of BoIFN orally every 12 hours. These pigs were not protected against challenge exposure to virulent transmissible gastroenteritis virus at 48 hours of age; disease and mortality were similar for these pigs and for control pigs not given BoIFN prior to challenge exposure. The BoIFN did not impair growth rate of pigs and did not cause obvious disease or lesions.
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PMID:Effect of recombinant DNA-derived bovine alpha-1 interferon on transmissible gastroenteritis virus infection in swine. 371 40

We looked for the presence of interferon in the digestive tract of newborn piglets infected with a virulent strain of transmissible gastroenteritis virus (Coronaviridae). High levels of type 1 interferon activity were found early in the disease in jejunal and ileal parts of the intestine as well as in the serum. Enterocytes appeared to be involved in the interferon synthesis. These findings raise the question of the role of interferon in the pathogenesis of viral enteritis.
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PMID:High interferon titer in newborn pig intestine during experimentally induced viral enteritis. 616 24

The interferon (IFN) response was studied in two different models of viral enteritis of the neonate. In rotavirus infected calves, IFN synthesis could be detected in the intestine and in the blood at the time of the diarrheic symptoms. A kinetic study on canulated calves suggested that systemic IFN is of intestinal origin. During TGEV infection (Transmissible gastroenteritis virus) of the newborn piglet, an acute disease which leads to 100% mortality, IFN was found at very high titres (1 000-20 000 u/ml) in the intestine, blood, urine and other organs. Intestinal IFN synthesis started some hours after the onset of diarrhea and was very transient, i.e. no more detectable two days p.i. Unlike the calf situation, IFN response in the serum lasted much longer suggesting an extra-intestinal origin. As a confirmation, piglets infected with cell-adapted strains had high levels of circulating IFN before the onset of intestinal IFN and of diarrhea. Virus and IFN were found in the lungs, due to a so far unrecognized tropism of TGEV for the macrophages. These findings indicate that the pathogenesis of TGEV is more complex than previously claimed.
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PMID:Interferon induction in rotavirus and coronavirus infections: a review of recent results. 620 63

Segments of jejunum in 5 to 6 days old piglets were surgically ligated, inoculated with transmissible gastroenteritis virus (TGEV) and 18 hours later the segments were fixed for histology or suspensions were prepared for plaque assay in swine testis (ST) cell cultures to determine the yield of virus. When the virulent Purdue strain of TGEV was used, villous atrophy was seen and TGEV antigen was demonstrated immunohistochemically in the villous enterocytes. The Miller M6 strain of virus produced less extensive lesions in the segments, but since it was titratable by plaque assay it was used in the subsequent yield reduction assays to determine the antiviral activity of interferon. When intestinal segments were inoculated simultaneously with either 3200 units of natural porcine interferon-alpha or up to 1000,000 units of recombinant human interferon-alpha 2 a, and TGEV, there no reductions in virus yield, although the same cytokines exerted an antiviral effect in ST cells treated in a similar way. However, virus yields were significantly reduced in intestinal segments in piglets treated parenterally with the synthetic interferon inducer polyinosinic: polycytidylic acid 6 hours before challenge of the segments with TGEV. There was also a trend for the antiviral effects of interferon induction before challenge to be augmented by the inclusion of interferon with the virus inoculum. It was concluded that interferon would be ineffective as a therapeutic for TGEV, although it might be useful prophylactically.
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PMID:Antiviral activity of interferon against transmissible gastroenteritis virus in cell culture and ligated intestinal segments in neonatal pigs. 801 30

A low frequency peripheral blood mononuclear cell (PBMC) subpopulation, referred to as natural interferon-producing (NIP) cells, is described as producing interferon-alpha (IFN-alpha) following contact with non-infectious viral structures, namely viral glycoproteins. These cells are characterized in vitro as non-T, non-B, MHC class II+ and CD4+ cells. In this study, NIP cells were analysed in vivo after an intravenous injection of UV-inactivated transmissible gastroenteritis virus in newborn piglets, which resulted in strong serum IFN-alpha production. Splenocytes, but not PBMC, were the IFN-alpha producers in vivo. Using double immunohistochemical labelling for both IFN-alpha and leukocyte markers, we established that splenic NIP cells were not T or B cells. The majority were MHC class II+ and only a minority expressed a macrophage marker. NIP cells were localized in contact with MHC class II-expressing cells and T cells, which suggested that NIP cells might modulate the antiviral immune response.
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PMID:In vivo induction of interferon-alpha in pig by non-infectious coronavirus: tissue localization and in situ phenotypic characterization of interferon-alpha-producing cells. 934 68

During the study's first stage, 284 homeless people from crisis and long-term accommodation sites were surveyed using stratified, systematic sampling. The second stage involved a survey of a convenience sample of 100 homeless people from squats and the streets. Participants completed a questionnaire, Mantoux testing was performed and blood taken for gamma-interferon assay, liver and renal function tests. The group's health status was poor, with 72% experiencing medical conditions in the preceding two years and 77% symptoms in the month prior to interview. Bronchitis, asthma and gastroenteritis were the most commonly reported conditions; productive and persistent coughing, shortness of breath and wheezing the commonest symptoms. Twenty-one per cent had Mantoux reactions 15 mm or greater, 28% a raised GGT and 19% a raised ALT. Seventy-seven per cent smoked, 74% were current drinkers, 28% had injected drugs at some time in their lives and 14% were regularly injecting drugs. Forty-four per cent had experienced mental illness, 49% of whom reported depression and 15% schizophrenia. Homeless people in Melbourne have poor health status and engage in behaviours that place their health at risk. The high number of respiratory and gastro-intestinal complaints, the high level of cigarette smoking and injecting drug use (IDU) and the proportion likely to be infected with Mycobacterium tuberculosis (MTb) are all issues with important health consequences. Participants recruited from the street had significantly poorer health and engaged in more risk behaviours than those from accommodation sites; those from the accommodated sample were more likely to be infected with Mtb.
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PMID:Health indicators and risks among people experiencing homelessness in Melbourne, 1995-1996. 965 74

Transmissible gastroenteritis virus (TGEV), an enteric coronavirus of swine, is a potent inducer of alpha interferon (IFN-alpha) both in vivo and in vitro. Incubation of peripheral blood mononuclear cells with noninfectious viral material such as inactivated virions or fixed, infected cells leads to early and strong IFN-alpha synthesis. Previous studies have shown that antibodies against the virus membrane glycoprotein M blocked the IFN induction and that two viruses with a mutated protein exhibited a decreased interferogenic activity, thus arguing for a direct involvement of M protein in this phenomenon. In this study, the IFN-alpha-inducing activity of recombinant M protein expressed in the absence or presence of other TGEV structural proteins was examined. Fixed cells coexpressing M together with at least the minor structural protein E were found to induce IFN-alpha almost as efficiently as TGEV-infected cells. Pseudoparticles resembling authentic virions were released in the culture medium of cells coexpressing M and E proteins. The interferogenic activity of purified pseudoparticles was shown to be comparable to that of TGEV virions, thus establishing that neither ribonucleoprotein nor spikes are required for IFN induction. The replacement of the externally exposed, N-terminal domain of M with that of bovine coronavirus (BCV) led to the production of chimeric particles with no major change in interferogenicity, although the structures of the TGEV and BCV ectodomains markedly differ. Moreover, BCV pseudoparticles also exhibited interferogenic activity. Together these observations suggest that the ability of coronavirus particles to induce IFN-alpha is more likely to involve a specific, multimeric structure than a definite sequence motif.
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PMID:Coronavirus pseudoparticles formed with recombinant M and E proteins induce alpha interferon synthesis by leukocytes. 976 3

A low frequency leukocyte subpopulation, referred to as natural interferon producing cells (NIPC) is able to produce high amounts of interferon alpha (IFN-alpha) following contact with noninfectious viral structures. In order to examine the possible leukocytic nature and bone marrow origin of NIPC, severe combined immunodeficiency (SCID) mice were reconstituted with porcine leukocyte populations, including bone marrow cells. At different times after reconstitution, enriched CD4 and CD45 positive porcine cells were isolated from various mouse organs and tested for the presence of porcine NIPC by porcine IFN-alpha specific ELISPOT assay, after in vitro stimulation by UV inactivated transmissible gastroenteritis virus (TGEV). Although engraftment of porcine cells in SCID mice was shown by flow cytometry and by the production of pig immunoglobulins, no IFN-alpha secreting cells could be detected. This result suggests that NIPC do not derive from bone marrow precursor cells, or that growth factors needed for in vivo expansion of porcine NIPC were absent in mice.
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PMID:Absence of porcine interferon alpha secreting cells in severe combined immunodeficiency (SCID) mice inoculated with porcine leukocytes. 985 Oct 13


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