Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| an enteric coronavirus infection of cats and its relationship to feline infectious peritonitis. | an enteric coronavirus that is antigenically closely related to feline infectious peritonitis virus (fipv) is ubiquitous in the cat population. this virus has been designated feline enteric coronavirus to differentiate it from fipv. the virus is shed in the feces by many seropositive cats; in catteries it is a cause of inapparent to mildly severe enteritis in kittens 6 to 12 weeks of age. the virus may produce a more severe enteritis in young specific-pathogen-free kittens. feline enteric corona ... | 1981 | 6267960 |
| in vitro properties of low- and high-passaged strains of transmissible gastroenteritis coronavirus of swine. | 1981 | 6267962 | |
| physicochemical properties of field and cell culture-attenuated strains of swine transmissible gastroenteritis (tge) coronavirus. | 1981 | 6269408 | |
| laboratory evaluation of selected disinfectants as virucidal agents against porcine parvovirus, pseudorabies virus, and transmissible gastroenteritis virus. | of a variety of disinfectants evaluated, only sodium hypochlorite and sodium hydroxide inactivated porcine parvovirus (ppv) after a 5-minute incubation period. after the same incubation time, pseudorabies and transmissible gastroenteritis viruses were inactivated by all of the disinfectants tested. when the incubation time was increased to 20 minutes, 2% glutaraldehyde and a double-strength concentration of a commercial formaldehyde preparation also inactivated ppv. formaldehyde vapor and ultrav ... | 1981 | 6269467 |
| thermal inactivation studies of a coronavirus, transmissible gastroenteritis virus. | the thermolability of transmissible gastroenteritis virus (tgev) was studied between 31 and 55 degrees c using two different strains. the loss of infectivity followed first order kinetics except at the highest temperature. the values of the thermodynamic parameters indicated that the mechanisms involved above and below 45 degrees c are clearly distinct. the rates of inactivation were greater at alkaline than at neutral ph, yet the name of the reaction appeared unchanged. using four independent s ... | 1981 | 6273497 |
| three-dimensional sequential study of the intestinal surface in experimental porcine cv 777 coronavirus enteritis. | 1981 | 6275638 | |
| coronavirus cell-associated rna-dependent rna polymerase. | 1981 | 6278878 | |
| the structure of the canine coronavirus. | 1981 | 6278898 | |
| isolation of transmissible gastroenteritis virus, pseudorabies virus, and porcine enterovirus from pharyngeal swabs taken from market-weight-swine. | pharyngeal swab samples were collected at a central iowa abattoir from 6,010 market-weight slaughter hogs from september 1, 1979 to august 31, 1980. the swab samples were examined for cytopathic viruses by inoculation of monolayer cultures of continuous line of swine testicular cells. of the 6,010 swab samples tested, transmissible gastroenteritis virus was isolated from 91 (1,51%), pseudorabies virus was isolated from 431 (7.17%), and porcine enterovirus was isolated from 21 (0.35%). although a ... | 1981 | 6278996 |
| [transmissible gastroenteritis in a swine-raising unit of 1,200 productive sows. 1. clinical course, disease control and piglet loss]. | 1981 | 6282232 | |
| [transmissible gastroenteritis in a swine raising unit of 1,200 productive sows. 2. results of serological follow-up studies]. | 1981 | 6282233 | |
| [transmissible gastroenteritis in a swine raising unit of 1,200 productive sows. 3. course of selection-based eradication]. | 1981 | 6282234 | |
| rna-dependent rna polymerase activity in coronavirus- infected cells. | an enzymatic activity which incorporates [3h]ump into acid-precipitable material in the presence of endogenous template was found in the cytoplasm of porcine cells infected with the transmissible gastroenteritis virus of swine. this activity was not found in uninfected control cells, nor was it found in purified virus. the activity was associated with the mitochondrial fraction of infected cells, suggesting that the enzyme is membrane bound. the activity required the presence of all three ribonu ... | 1982 | 6283135 |
| [inhibiting activity of amantadine (1-aminoadamantane) on the transmissible gastroenteritis virus of swine in cell cultures]. | studies were carried out on the inhibiting activity of amantadine - 1-amino adamantine (1-aa) on the virus of swine transmissive gastroenteritis, rakovski strain, in cell cultures of pig kidney and thyroid gland. the inhibiting agent was tested in concentration of 6.25 to 100 microgram/cm3. parallel titrations with and without 1-aa (25, 50, and 100 microgram/cm3) were used to establish the maximum difference in the titers 2 lg. the effect of inhibition was manifested at minimum concentration of ... | 1981 | 6283726 |
| applications of peroxidase-antiperoxidase staining technique for detection of transmissible gastroenteritis virus in pigs. | the peroxidase-antiperoxidase (pap) staining technique was used for the detection of transmissible gastroenteritis virus (tgev) in small intestines of tgev-infected 8-week-old pigs and in infected mcclurkin pig testicle cells by means of light microscopy. the specific-positive reaction was characterized by the presence of many brown granules of various sizes in the cytoplasm of infected cells. nonspecific granules caused by endogenous peroxidases in the cytoplasm of eosinophils stained by pap we ... | 1982 | 6283953 |
| intestinal, pulmonary, and serum antibody responses of feeder pigs exposed to transmissible gastroenteritis virus by the oral and the oral-intranasal routes in inoculation. | specific antibodies against transmissible gastroenteritis (tge) virus produced as a result of oral and oral-intranasal viral exposure of feeder pigs were isolated by molecular sieve column chromatography of lung wash, intestinal fluid, and serum samples. selected fractions were analyzed for neutralizing antibody activity. oral inoculation gave a predominantly immunoglobulin (ig) g antibody response in lung wash and serum, as compared with the response in intestinal fluid in which neutralizing an ... | 1982 | 6283957 |
| [effect of amantadine (1-aminoadamantan) on different phases of the replicative cycle of transmissible gastroenteritis virus of swine]. | 1982 | 6287708 | |
| [detection of antibodies against the virus causing viral gastroenteritis in swine using the modified autoradiography test]. | a modified method for autoradiographic determination of antibodies to the virus of transmissible gastroenteritis of swine was developed. it is based on the actual reaction between antigen bound in cells of the infected cell cultures and antibodies in tested sera, which is visualized, by help of rabbit antibodies marked 125j (125j rasw igg antibody) to porcine igg, on a sensitive radiograph and evaluated on the basis of darkening at the point of positive immunological reaction. specificity of the ... | 1982 | 6291217 |
| [determination of the quantity of minimal antigen for oral immunization of sows against transmissible gastroenteritis of swine using riems tge vaccine]. | 1982 | 6291484 | |
| [effect of coronavirus infection on the delayed hypersensitivity reaction]. | 1982 | 6292669 | |
| serum antibody responses of neonatal and young adult pigs to transmissible gastroenteritis coronavirus. | serum titers of virus-neutralizing (vn) antibody were 10 to 16 times higher in neonatal pigs than in young adult pigs, after single oral doses of virulent transmissible gastroenteritis virus (tgev). to determine the reason for this higher response, sera from neonatal and young adult pigs, 18 to 21 days after exposure to tgev, were collected and assayed for vn antibody by plaque reduction. in addition, sera of vn-positive and vn-negative neonatal pigs were analyzed for immunoglobulin classes by r ... | 1982 | 6293157 |
| studies of enteric coronaviruses in a feline cell line. | development is reported of a feline cell line which can support the growth of coronaviruses from canine (ccv), feline (fipv) and porcine (tgev) species. the cell culture has been serially transferred over 100 times and has retained its initial growth requirements, proliferative capacity and morphologic features. each virus had specific growth characteristics in this cell culture although all produced a similar cpe and plaques under agar. cross neutralization studies demonstrated a two-way relati ... | 1982 | 6298992 |
| neonatal diarrhea of pigs in quebec: infectious causes of significant outbreaks. | to evaluate the relative importance of the various enteropathogens causing neonatal diarrhea in quebec farrowing operations, observations were made on 749 diarrheic pigs from 325 outbreaks of diarrhea. they were one to 15 days of age, and were obtained alive for necropsy generally within 48 hours of the onset of diarrhea. some pigs were from severe, explosive outbreaks of diarrhea with high morbidity and mortality rates, while others were from herds with chronic neonatal diarrhea with lower morb ... | 1983 | 6299483 |
| [comparative studies using the immunofluorescence technic in experimental transmissible gastroenteritis and rotavirus infection of piglets]. | 1983 | 6303246 | |
| antibody-dependent cell-mediated cytotoxicity and spontaneous cell-mediated cytotoxicity against cells infected with porcine transmissible gastroenteritis virus. | the objective of this study was to determine whether porcine peripheral blood leukocytes and intestinal intraepithelial leukocytes can mediate antibody-dependent cell-mediated cytotoxicity and spontaneous cell-mediated cytotoxicity against target cells infected with transmissible gastroenteritis virus. peripheral blood leukocytes collected from six young adult pigs and intraepithelial leukocytes from a further five pigs were used as effector cells in chromium release assays against pk-15 cells p ... | 1983 | 6315197 |
| identification of porcine transmissible gastroenteritis virus in house flies (musca domestica linneaus). | transmissible gastroenteritis (tge) virus was detected in house flies (musca domestica linneaus) by staining with specific fluorescent antibody. the flies were collected within a swine confinement facility in which tge was enzootic. laboratory-reared flies were infected experimentally with tge virus and the virus was recovered from the insects for 72 hours after infection. the tge virus was identified both by the fluorescent antibody technique and by isolation in cell culture. the nature of plaq ... | 1983 | 6316821 |
| a viral subunit immunogen for porcine transmissible gastroenteritis. | an immunogenic component was isolated from both the illinois (propagated in young swine) and the miller (cell culture-adapted) strains of porcine transmissible gastroenteritis (tge) virus. the viral subunit was released from the virion by sonication and was separated from intact virus and other viral components by isopycnic centrifugation. it had a buoyant density in sucrose of 1.02 g/ml. further purification consisted of gel filtration through sephadex g200, in which process the immunogen, with ... | 1983 | 6316850 |
| replication of transmissible gastroenteritis coronavirus (tgev) in swine alveolar macrophages. | several strains of the enteropathogenic coronavirus transmissible gastroenteritis virus (tgev) have been shown to replicate in alveolar macrophages maintained in vitro. a distinct cytopathic effect was observed at a multiplicity of infection greater than or equal to 0.1. infected cells released infectious virus. the extent of both virus production and cell destruction was highly dependent upon the virus input. at low input, cell viability was affected only slightly, and a delayed and persistent ... | 1984 | 6319578 |
| macrotiter assay for coronavirus-neutralizing activity in cats using a canine continuous cell line (a-72). | a heterologous neutralization assay for feline infectious peritonitis virus serology was developed using a single continuous cell line of canine origin, a-72, which is susceptible to cytopathic infection with both transmissible gastroenteritis virus of pigs and canine coronavirus. of several coronavirus isolates tested, the 1-71 isolate of canine coronavirus demonstrated the most effective neutralization by serum and body fluids of cats with histopathologically confirmed feline infectious perito ... | 1983 | 6319813 |
| significance of lysosomes in the morphogenesis of coronaviruses. | virus-containing electron-dense membrane-bound cytoplasmic bodies are described in tracheal epithelial cells of chickens infected with infectious bronchitis virus and in intestinal epithelial cells of swine infected with porcine epidemic diarrhea virus. using silver-methenamine staining, phosphotungstic acid staining and acid phosphatase enzyme cytochemical staining of ultra-thin sections, these bodies were shown to be virus-containing secondary lysosomes and residual bodies. the accumulation of ... | 1984 | 6320768 |
| defective replication of porcine transmissible gastroenteritis virus in a continuous cell line. | 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 ll ... | 1984 | 6331129 |
| antibody-dependent and spontaneous cell-mediated cytotoxicity against transmissible gastroenteritis virus infected cells by lymphocytes from sows, fetuses and neonatal piglets. | the purpose of this study was to investigate the ontogeny in the pig of effector lymphocytes mediating antibody-dependent and spontaneous cell-mediated cytotoxicity against target cells infected with transmissible gastroenteritis virus. the same activities were also studied in sows in late pregnancy and early lactation. peripheral blood lymphocytes and intraepithelial lymphocytes collected from piglets during the first week of life failed to mediate cytolysis as determined by chromium release as ... | 1984 | 6332661 |
| hypoglycemia: a factor associated with low survival rate of neonatal piglets infected with transmissible gastroenteritis virus. | the main purpose of this work was to study changes in the balance of fluids, electrolytes and blood metabolites in neonatal piglets with severe transmissible gastroenteritis. six two day old conventional piglets were infected with transmissible gastroenteritis virus while six others were used as normal controls. blood samples were collected in heparin when the infected piglets were moribund. the following variables were measured: packed red cell volume, total plasma protein and bicarbonate, bloo ... | 1984 | 6478297 |
| passive immunity to transmissible gastroenteritis virus: intramammary viral inoculation of sows. | sows were injected intramammarily with live-attenuated tge virus, an enteric coronavirus--one sow during pregnancy and three sows during lactation. all sows were tge antibody seronegative prior to inoculation except for one naturally infected sow inoculated during lactation. the animal injected during pregnancy had primarily igg tge antibodies in milk from all glands. by contrast, sows injected during lactation had iga and igm initially, and later iga and igg tge antibodies in milk from injected ... | 1983 | 6575719 |
| colonic compensation in transmissible gastroenteritis of swine. | absorption of water and electrolytes by the small and large intestine was examined using a nonabsorbable marker technique in 3-day-old and 3-wk-old pigs. one-half of the pigs in each group were orally infected with transmissible gastroenteritis virus; the remaining pigs served as controls. three-day-old control pigs concentrated the nonabsorbable fluid marker twelve fold along the small and large intestine, indicating an efficiency of about 95% in absorption of the exogenous daily fluid load pre ... | 1984 | 6714576 |
| influence of coronavirus (transmissible gastroenteritis) infection on jejunal myoelectrical activity of the neonatal pig. | four silver-silver chloride electrodes were surgically implanted at 5-cm intervals on the jejunal serosa of 7 neonatal pigs. daily recordings, 7 h in duration, were made from each piglet beginning 3 days after surgery. characteristic migrating motility complexes and short, distinct (2.5-5.0 s), rapidly aboral migrating bursts of intense spike activity ("migrating action potential complexes") were seen in all preinfection recordings. piglets were inoculated with a 1-ml oral dose of a 0.1% gut sus ... | 1984 | 6735081 |
| serum immunoglobulin a antibody response in swine infected with transmissible gastroenteritis virus, as determined by indirect immunoperoxidase antibody test. | using an immunoperoxidase antibody test, the serum immunoglobulin (ig) a antibody titer was determined in swine naturally infected with transmissible gastroenteritis (tge; group a), swine inoculated orally with high-virulent tge virus (group b), and swine inoculated im (group c) or orally (group d) with low-virulent tge virus. studies were then made on the relationship between active immunity to tge and the serum iga antibody titer. in group a swine, serum iga antibody and virus-neutralizing (vn ... | 1981 | 7023294 |
| changes in gut-associated lymphoid tissues of the small intestine of eight-week-old pigs infected with transmissible gastroenteritis virus. | the responses of the interepithelial lymphocytes (iel) and aggregated lymph nodules (aln; peyer's patches) of the small intestines of 8-week-old pigs to transmissible gastroenteritis virus (tgev) infection were characterized at 12, 18, and 24 hours after pigs were inoculated. there was no significant difference in numbers of iel between control and tgev-infected pigs at 12 and 18 hours. however, in pigs examined at 24 hours, there was a significant decrease in the number of iel in the duodenum a ... | 1982 | 7091819 |
| secretory immune response in intestinal mucosa and salivary gland after experimental infection of pigs with transmissible gastroenteritis virus. | pigs 8 to 10 weeks of age were orally infected with transmissible gastroenteritis (tge) virus or infected by inoculation of the virus into thirty-vella loops of jejunum. concentrations of immunoglobulin (ig) a, igm, and igg in serum, saliva, jejunal secretions, loop secretions, and bile were determined by solid-phase radioimmunoassay for tge virus-infected and control pigs. a multiple-staining fluorescent antibody technique was used to determine the relative numbers of iga-, igm-, and igg-produc ... | 1980 | 7192522 |
| an immunohistochemical investigation of porcine epidemic diarrhoea. | a sudden outbreak of epidemic diarrhoea of piglets occurred in japan, the principal features being watery diarrhoea, dehydration and high mortality in newborn animals. the microscopical lesions were villous atrophy in the small intestine, the villous enterocytes being vacuolated and cuboidal in shape. the villus-crypt ratio was severely reduced, varying from 1:1 to 3:1. transmission electron microscopy showed numerous coronaviruses within the cytoplasm of enterocytes and among microvilli. specif ... | 1995 | 7490338 |
| induction of antibodies protecting against transmissible gastroenteritis coronavirus (tgev) by recombinant adenovirus expressing tgev spike protein. | ten recombinant adenoviruses expressing either fragments of 1135, 1587, or 3329 nt or the full-length spike gene of transmissible gastroenteritis coronavirus (tgev) have been constructed. these recombinants produce s polypeptides with apparent molecular masses of 68, 86, 135, and 200 kda, respectively. expression of the recombinant antigen driven by ad5 promoters was inhibited by the insertion of an exogenous sv-40 promoter. most of the recombinant antigens remain intracytoplasmic in infected ce ... | 1995 | 7491775 |
| induction of transmissible gastroenteritis coronavirus specific immune responses using vectors with enteric tropism. | 1995 | 7502852 | |
| molecular mimicry between fc receptors and viral antigens. | molecular mimicry has been characterized as the presence of common epitopes, either linear or conformational, shared by host and microbial determinants. such cross-reactivity may lead to an autoimmune disease. on the other hand molecular mimicry between certain viral proteins and host determinant may protect invading virus to be eliminated by immune system and may promote persistence. in this mini-review i discuss the molecular mimicry of s peplomer protein of mouse hepatitis virus, strain jhm ( ... | 1994 | 7503651 |
| epitopes on the spike protein of a nephropathogenic strain of infectious bronchitis virus. | infectious bronchitis virus (ibv), the first coronavirus described, was initially associated with severe respiratory disease. however, outbreaks have more recently also been associated with nephropathogenesis. topographically interrelated antigenic determinants of the nephropathogenic gray strain of ibv were characterized using eleven monoclonal antibodies (mabs). four mabs (igg 2a kappa) defined epitopes that were both conformation-independent and group specific, reacting with gray, arkansas (a ... | 1993 | 7504916 |
| cs31a capsule-like antigen as an exposure vector for heterologous antigenic determinants. | cs31a is a multimeric surface protein surrounding certain enterotoxigenic and septicemic bovine escherichia coli strains. the possibility of using cs31a as a carrier of foreign antigenic determinants was investigated. introduction of heterologous viral epitopes into the cs31a major subunit, clpg, was successfully performed in the v3 region of the molecule which encodes for an immunodominant linear epitope. e. coli k-12 strains producing the hybrid cs31a molecules or the purified chimeric protein ... | 1994 | 7514578 |
| enhancement of fip in cats immunised with vaccinia virus recombinants expressing ccv and tgev spike glycoproteins. | 1993 | 7516108 | |
| induction of an immune response to transmissible gastroenteritis coronavirus using vectors with enteric tropism. | 1993 | 7516110 | |
| permissible peptide insertions surrounding the signal peptide-mature protein junction of the clpg prepilin: cs31a fimbriae of escherichia coli as carriers of foreign sequences. | the clpg gene, expressing the escherichia coli major cs31a fimbrial subunit clpg, was subjected to random mutagenesis by insertion of an ecori linker and a kanamycin-resistance (kmr) cassette into the multiple newly generated ecori sites. the kmr gene was then excised by psti, which left a 48-bp linker representing the heterologous sequence. the same procedure was followed to introduce a synthetic oligodeoxyribonucleotide (oligo) corresponding to epitope c from the spike protein s from the porci ... | 1994 | 7523252 |
| characterization of the iga and subclass igg responses to neutralizing epitopes after infection of pregnant sows with the transmissible gastroenteritis virus or the antigenically related porcine respiratory coronavirus. | in this study, we have investigated the characteristics of secreted iga and other classes of ig induced after vaccination of sows with transmissible gastroenteritis virus (tgev) or the antigenically related porcine respiratory coronavirus (prcv). both viruses induced the secretion of neutralizing antibodies of different classes in the sows' milk, but these protected suckling piglets against tgev to different degrees. quantitative differences in the induction of iga by both viruses were found amo ... | 1994 | 7523577 |
| major receptor-binding and neutralization determinants are located within the same domain of the transmissible gastroenteritis virus (coronavirus) spike protein. | the spike glycoprotein (s) of coronavirus, the major target for virus-neutralizing antibodies, is assumed to mediate the attachment of virions to the host cell. a 26-kilodalton fragment proteolytically cleaved from transmissible gastroenteritis virus (tgev) s protein was previously shown to bear two adjacent antigenic sites, a and b, both defined by high-titer neutralizing antibodies. recombinant baculoviruses expressing c-terminal truncations of the 26-kilodalton region were used to localize fu ... | 1994 | 7525985 |
| frequency of interferon-alpha-secreting blood leukocytes in irradiated and bone-marrow-grafted pigs. | the effects of irradiation were studied on porcine interferon-alpha (ifn-alpha) secreting cells (ifn-alpha sc). ifn-alpha sc were characterized by an elispot assay on non-adherent pbmc following incubation with the transmissible gastroenteritis coronavirus. in vitro irradiation of pbmc was followed by a decrease in the number of ifn-alpha sc while ifn-gamma production and cell viability were not affected. these data indicate that porcine ifn-alpha sc are relatively radiosensitive. indeed, the fr ... | 1995 | 7550400 |
| site-specific alteration of transmissible gastroenteritis virus spike protein results in markedly reduced pathogenicity. | the pathogenicity of neutralization-resistant mutants of the enteric coronavirus transmissible gastroenteritis virus (tgev) was examined in the newborn piglet. the parental virus (purdue-115 strain), as well as several mutants selected using monoclonal antibodies (mabs) directed to antigenic sites a and b, caused an acute enteritis with 100% mortality. by contrast, most of the site d (mab 40.1) mutants exhibited a strongly reduced enteropathogenicity, leading to the survival of animals inoculate ... | 1995 | 7561760 |
| a transmissible gastroenteritis coronavirus nucleoprotein epitope elicits t helper cells that collaborate in the in vitro antibody synthesis to the three major structural viral proteins. | four strong t cell epitopes have been identified studying the blastogenic response of lymphocytes from haplotype-defined transmissible gastroenteritis virus (tgev) immune miniswine to sixty-one 15-mer synthetic peptides. three of these epitopes are located on the nucleoprotein (n46, amino acids 46 to 60; n272, amino acids 272 to 286; and n321, amino acids 321 to 335), and one on the membrane protein (m196, amino acids 196 to 210). n321 peptide induced the highest t cell response and was recogniz ... | 1995 | 7571447 |
| membrane protein molecules of transmissible gastroenteritis coronavirus also expose the carboxy-terminal region on the external surface of the virion. | the binding domains of four monoclonal antibodies (mabs) specific for the m protein of the pur46-mad strain of transmissible gastroenteritis coronavirus (tgev) have been located in the 46 carboxy-terminal amino acids of the protein by studying the binding of mabs to recombinant m protein fragments. immunoelectron microscopy using these mabs demonstrated that in a significant proportion of the m protein molecules, the carboxy terminus is exposed on the external surface both in purified viruses an ... | 1995 | 7636969 |
| antiviral action of interferon-alpha against porcine transmissible gastroenteritis virus. | swine testis (st) cell cultures were treated with various doses of recombinant human interferon-alpha 2a (ifn), and assayed for 2',5' oligoadenylate synthetase (2-5 a synthetase) activity. treatment with 100 or 1000 units/ml of ifn resulted in increased 2-5 a synthetase activity, but there was no significant response to 1 unit/ml of ifn. titres of porcine transmissible gastroenteritis virus (tgev) were reduced between 6 and 15 hours post-infection in st cells treated with 1000 or 2500 units/ml o ... | 1995 | 7653029 |
| quantification of individual subgenomic mrna species during replication of the coronavirus transmissible gastroenteritis virus. | a biotinylated-oligonucleotide-based method was used to isolate the subgenomic mrnas of the coronavirus transmissible gastroenteritis virus (tgev) to investigate the amounts of the mrnas produced at early, middle and late times in the replication cycle. tgev mrna 6, which encodes the n protein, was observed to be the most abundant species throughout the replication cycle. the ratios of mrna 6 to the other mrnas were 1:0.11 (mrna 2), 1:0.16 (mrnas 3 and 4) and 1:0.37 (mrna 5) at 12 h post-infecti ... | 1995 | 7653093 |
| lactogenic immunity and milk antibody isotypes to transmissible gastroenteritis virus in sows exposed to porcine respiratory coronavirus during pregnancy. | passive protection provided by sows inoculated with the virulent miller strain of transmissible gastroenteritis virus (tgev), or the isu-1 strain of porcine respiratory coronavirus (prcv), or both was evaluated in nursing pigs challenge exposed with virulent tgev. four sows (group b) were inoculated with prcv oronasally twice at 4 and 2 weeks before parturition; 1 sow (group c) was inoculated similarly, but in 2 subsequent pregnancies; and 2 sows (group d) were oronasally primed with prcv at 4 w ... | 1995 | 7653882 |
| investigation of the control of coronavirus subgenomic mrna transcription by using t7-generated negative-sense rna transcripts. | the subgenomic mrnas of the coronavirus transmissible gastroenteritis virus (tgev) are not produced in equimolar amounts. we have developed a reporter gene system to investigate the control of this differential subgenomic mrna synthesis. transcription of mrnas by the tgev polymerase was obtained from negative-sense rna templates generated in situ from dna containing a t7 promoter. a series of gene cassettes was produced; these cassettes comprised the reporter chloramphenicol acetyltransferase (c ... | 1995 | 7666523 |
| identification of antigenic sites mediating antibody-dependent enhancement of feline infectious peritonitis virus infectivity. | we have previously demonstrated antibody-dependent enhancement of feline infectious peritonitis virus (fipv) infection of macrophages using both virus-specific antisera and monoclonal antibodies (mabs) to the spike (s) protein of fipv. to increase our understanding of this phenomenon, six representative mabs from a previously documented group of 12 enhancing mabs were used to identify epitopes that mediate antibody-dependent enhancement of fipv infectivity. analysis of the results of kinetics-ba ... | 1993 | 7682252 |
| neutralization and fusion inhibition activities of monoclonal antibodies specific for the s1 subunit of the spike protein of neurovirulent murine coronavirus jhmv c1-2 variant. | the cleavage products of the spike (s) protein, the s1 and s2 subunits, of the highly neurovirulent murine coronavirus (mhv) jhmv c1-2 variant were identified by immunoprecipitation of virus-infected cell lysates after treatment with urea and 2-mercaptoethanol. by this method 14 monoclonal antibodies (mabs) raised against the s protein of the c1-2 variant were revealed to react with the s1 subunit and one with the s2 subunit. these 14 mabs were classified into the following three groups: (a) mab ... | 1993 | 7687650 |
| passive protection of piglets by recombinant baculovirus induced transmissible gastroenteritis virus specific antibodies. | sera of pigs immunized with parts of the transmissible gastroenteritis virus (tgev) spike (s) protein expressed by recombinant baculoviruses were tested, together with a tgev hyperimmune antiserum, for their abilities to protect three-day-old piglets against tgev infection. the piglets were infected with virulent tgev and the sera were given orally 3 h before infection, together with the virus, and every 6 h postinfection during the 30 h of the experiment. virus shedding was monitored by tgev is ... | 1995 | 7704846 |
| localization of antigenic sites of the s glycoprotein of feline infectious peritonitis virus involved in neutralization and antibody-dependent enhancement. | the s glycoprotein of feline infectious peritonitis virus (fipv) has been shown to contain the antigenic sites responsible for eliciting both neutralization and antibody-dependent enhancement. to determine the region of s responsible, overlapping dna fragments spanning the entire s gene were cloned and expressed as fusion proteins by in vitro transcription and translation. fusion proteins containing relevant epitopes were identified by radioimmunoprecipitation with neutralizing and enhancing fip ... | 1995 | 7707508 |
| sequence comparison of porcine respiratory coronavirus isolates reveals heterogeneity in the s, 3, and 3-1 genes. | four new porcine respiratory coronavirus (prcv) isolates were genetically characterized. subgenomic mrna patterns and the nucleotide sequences of the 5' ends of the s genes, the open reading frame (orf) 3/3a genes, and the orf 3-1/3b genes of these prcv isolates were determined and compared with those of other prcv and transmissible gastroenteritis virus (tgev) isolates. the s, orf 3/3a, and orf 3-1/3b genes are under intense study because of their possible roles in determining tissue tropism an ... | 1995 | 7707547 |
| ontogeny of interferon alpha secreting cells in the porcine fetal hematopoietic organs. | we examined the ontogeny of ifn-alpha secreting cells (ifn-alpha sc) in different hematopoietic organs and blood of porcine fetuses at different stages of gestation. cells were induced to produce ifn-alpha by incubation with the coronavirus tgev and ifn-alpha sc were detected by elispot. a striking finding was that ifn-alpha sc could be detected in the fetal liver as early as at 26 days of gestation, i.e., during the first quarter of gestation, a period at which t-cell markers could not be detec ... | 1994 | 7721334 |
| molecular cloning and sequence determination of the peplomer protein gene of feline infectious peritonitis virus type i. | cdna clones spanning the entire region of the peplomer (s) gene of feline infectious peritonitis virus (fipv) type i strain ku-2 were obtained and their complete nucleotide sequences were determined. a long open reading frame (orf) encoding 1464 amino acid residues was found in the gene, which was 12 residues longer than the orf of the fipv type ii strain 79-1146. the sequences of fipv type i and mainly -tpv type ii were compared. the homologies at the n- (amino acid residues 1-693) and c- (resi ... | 1995 | 7733820 |
| molecular mimicry between fc receptor and s peplomer protein of mouse hepatitis virus, bovine corona virus, and transmissible gastroenteritis virus. | we have previously demonstrated molecular mimicry between the s peplomer protein of mouse hepatitis virus (mhv) and fc gamma r (fc gamma r). a monoclonal antibody (mab) to mouse fc gamma r (2.4g2 anti-fc gamma r mab), purified rabbit immunoglobulin, but not their f(ab')2 fragments, as well as mouse and rat igg, immunoprecipitated (1) recombinant s peplomer protein expressed by a vaccinia virus recombinant in human, rabbit, and mouse cells, and (2) natural s peplomer protein from cells infected w ... | 1995 | 7768529 |
| evaluation of a blocking elisa using monoclonal antibodies for the detection of porcine epidemic diarrhea virus and its antibodies. | two blocking enzyme-linked immunosorbent assays (elisas) involving the use of monoclonal antibodies (mab) as capture and detecting agents and an indirect fluorescence test (ift) were used for the detection of porcine epidemic diarrhea virus (pedv) antigen or its antibodies. in the elisa for viral antigen detection, the blocking step is accomplished by incubation of fecal samples, in duplicate wells, with pedv-specific positive or negative serum, whereas in the elisa for antibody detection the bl ... | 1995 | 7779966 |
| mhv-a59 enters polarized murine epithelial cells through the apical surface but is released basolaterally. | coronaviruses have a marked tropism for epithelial cells. entry and release of the porcine transmissible gastroenteritis virus (tgev) is restricted to apical surfaces of polarized epithelial cells, as we have recently shown (j. w. a. rossen, c. p. j. bekker, w. f. voorhout, g. j. a. m. strous, a. van der ende, and p. j. m. rottier, 1994, j. virol. 68, 7966-7973). in this paper we analyze the interactions of mouse hepatitis coronavirus a59 (mhv-a59) with polarized murine kidney cells (mtal) grown ... | 1995 | 7793080 |
| [lactogenic immunity and vaccinal protection in swine]. | 1995 | 7795689 | |
| tropism and immunoprotection in transmissible gastroenteritis coronaviruses. | 1995 | 7796947 | |
| paracrine activities of porcine trophoblastic interferons. | interferon-gamma (ifn-gamma) and a type i ifn (spi ifn) are transiently coexpressed by trophoblastic cells of pig conceptuses at implantation between day 12 and day 20 of gestation. the local effects of these trophoblastic ifns were examined on endometrial cells and on trophoblast by measuring antiviral activity and the induction of (2',5')-oligoadenylate synthetase activity. trophoblastic vesicles were shown to be susceptible to infection by vesicular stomatitis virus and transmissible gastroen ... | 1994 | 7799312 |
| interaction of mouse hepatitis virus (mhv) spike glycoprotein with receptor glycoprotein mhvr is required for infection with an mhv strain that expresses the hemagglutinin-esterase glycoprotein. | in addition to the spike (s) glycoprotein that binds to carcinoembryonic antigen-related receptors on the host cell membrane, some strains of mouse coronavirus (mouse hepatitis virus [mhv]) express a hemagglutinin esterase (he) glycoprotein with hemagglutinating and acetylesterase activity. virions of strains that do not express he, such as mhv-a59, can infect mouse fibroblasts in vitro, showing that the he glycoprotein is not required for infection of these cells. the present work was done to s ... | 1995 | 7815557 |
| immunity to transmissible gastroenteritis virus and porcine respiratory coronavirus infections in swine. | despite the pioneering efforts to identify correlates of passive immunity to transmissible gastroenteritis virus (tgev), effective vaccines for the control of tge in suckling pigs have remained elusive. the initial concept of an enteromammary immunologic axis in monogastrics originated from studies of lactogenic immunity to tgev in swine. these studies revealed that infection of pregnant swine with virulent tgev stimulated high titers of siga antibodies in milk which correlated with protection o ... | 1994 | 7856068 |
| complete sequence (20 kilobases) of the polyprotein-encoding gene 1 of transmissible gastroenteritis virus. | the entire nucleotide sequence of cloned cdnas containing the 5'-untranslated region and gene 1 of purdue-115 strain of transmissible gastroenteritis virus (tgev) was determined. this completes the sequence of the tgev genome, which is 28,579 nucleotides long. the gene 1 is composed of two large open reading frames, orf1a and orf1b, which contain 4017 and 2698 codons, respectively (stop excluded). a brief, three-codon-long orf is present upstream of orf1a. orf1b overlaps orf1a by 43 bases in the ... | 1995 | 7856095 |
| evaluation of rotavirus infection and diarrhea in iowa commercial pigs based on an epidemiologic study of a population represented by diagnostic laboratory cases. | group a, b, and c rotaviruses were identified in 9% (96/1,048) of pig fecal specimens submitted to the iowa state university veterinary diagnostic laboratory during 1987 and 1988. six of the rotaviruses were group b, 5 were group c, and the remaining 89% were group a. of the rotavirus cases with more than 1 serotype, 5 were multiple group a serotypes, 1 involved a group a and b serotype, and 1 included 2 group c serotypes. a retrospective epidemiologic evaluation of pig diarrhea in herds of orig ... | 1994 | 7858020 |
| pseudorabies and transmissible gastroenteritis: a serological survey in south africa. | two specific and sensitive, indirect enzyme-linked immunosorbent assays (elisas) utilizing a protein g-peroxidase conjugate were developed to detect antibodies to the pseudorabies virus (prv) and the transmissible gastroenteritis virus (tgev) in pig sera. sera from 5,337 pigs, obtained from various abattoirs in south africa, were tested with both elisas. no serological evidence of infection with either prv or tgev was found in any of the pigs tested. | 1994 | 7898899 |
| prevalence of infections with enzootic respiratory and enteric viruses in feeder pigs entering fattening herds. | the prevalence of infections with h1n1- and h3n2-influenza viruses, porcine respiratory coronavirus (prcv), transmissible gastroenteritis virus (tgev) and porcine epidemic diarrhoea virus (pedv) in feeder pigs shortly after their entry into fattening units was examined. ten groups of pigs with acute respiratory disease during the months september to october 1991 and seven groups of pigs with acute diarrhoea during the months february to march 1992 were investigated. on arrival in the fattening h ... | 1994 | 7900243 |
| further characterization of aminopeptidase-n as a receptor for coronaviruses. | we recently reported that porcine aminopeptidase-n (papn) acts as a receptor for transmissible gastroenteritis virus (tgev). in the present work, we addressed the question of whether tgev tropism is determined only by the virus-receptor interaction. to this end, different non-permissive cell lines were transfected with the porcine apn cdna and tested for their susceptibility to tgev infection. the four transfected cell lines shown to express papn at their membrane became sensitive to infection. ... | 1993 | 7911642 |
| determinants essential for the transmissible gastroenteritis virus-receptor interaction reside within a domain of aminopeptidase-n that is distinct from the enzymatic site. | the swine-specific coronavirus transmissible gastroenteritis virus (tgev) uses pig aminopeptidase-n (papn) as a cellular receptor. we showed that the human aminopeptidase-n (hapn) cannot substitute for papn in this respect, although the two enzymes have 80% amino acid sequence identity. in order to map the tgev binding site on papn, we constructed a series of apn cdna chimeras between papn and hapn and analyzed them for their capacity to confer infectivity. the region between residues 717 and 81 ... | 1994 | 7913510 |
| three new isolates of porcine respiratory coronavirus with various pathogenicities and spike (s) gene deletions. | three new isolates of porcine respiratory coronavirus (prcv) were isolated and partially characterized. these prcv isolates showed a selective tropism for respiratory tissue and were antigenically related to transmissible gastroenteritis virus. pcr amplification of the 5' half of the spike (s) genes of the three prcv isolates indicated that a large deletion, characteristic of prcv, was present. by using cdna probes specific for the transmissible gastroenteritis virus s gene, the pcr products wer ... | 1994 | 7929779 |
| evidence for a putative second receptor for porcine transmissible gastroenteritis virus on the villous enterocytes of newborn pigs. | aminopeptidase-n (apn) has been identified [b. delmas, j. gelfi, r. l'haridon, l. k. vogel, h. sjostrom, o. noren, and h. laude, nature (london) 357:417-420, 1992] as a major receptor for porcine transmissible gastroenteritis virus (tgev). binding of tgev to villous enterocytes from the jejuna of newborn pigs is saturable and at a higher level than that of binding of virus to newborn cryptal enterocytes or to enterocytes from older piglets (h. m. weingartl and j. b. derbyshire, vet. microbiol. 3 ... | 1994 | 7933108 |
| entry and release of transmissible gastroenteritis coronavirus are restricted to apical surfaces of polarized epithelial cells. | the transmissible gastroenteritis coronavirus (tgev) infects the epithelial cells of the intestinal tract of pigs, resulting in a high mortality rate in piglets. this study shows the interaction of tgev with a porcine epithelial cell line. to determine the site of viral entry, llc-pk1 cells were grown on permeable filter supports and infected with tgev from the apical or basolateral side. initially after plating, the virus was found to enter the cells from both sides. during further development ... | 1994 | 7966587 |
| immunogenicity of the s protein of transmissible gastroenteritis virus expressed in baculovirus. | seven fragments of the spike (s) gene cdna of transmissible gastroenteritis virus (tgev), as well as the full length cdna, were cloned and expressed in baculovirus vectors. piglets were immunized with cells infected with the recombinant viruses. each of the recombinants induced tgev-specific antibodies detected in a fixed cell enzyme immunoassay. the amino terminal half of the s protein, containing all four major antigenic sites (a, b, c and d), and encoded by a 2.2 kb fragment of the s gene, in ... | 1994 | 7979998 |
| molecular characterization of attenuated vaccine strains of transmissible gastroenteritis virus. | previous studies in our laboratory demonstrated that 2 attenuated strains of transmissible gastroenteritis virus (tgev) contain deletions affecting messenger (m) rnas 2, 3, or 4. in this report, we have compared mrnas of four modified-live virus vaccines for tgev with the virulent miller pp3 isolate to determine whether any transcriptional patterns are shared among attenuated strains. using northern blot analysis, all vaccine viruses expressed mrnas indistinguishable in size from those of miller ... | 1994 | 8011775 |
| antiviral activity of interferon against transmissible gastroenteritis virus in cell culture and ligated intestinal segments in neonatal pigs. | 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 ... | 1994 | 8017030 |
| lymphocyte proliferation responses of pigs inoculated with transmissible gastroenteritis virus or porcine respiratory coronavirus. | cell-mediated immunity was evaluated in intestinal, respiratory, and systemic lymphoid tissues of pigs exposed when 11 days old to virulent transmissible gastroenteritis virus (tgev), attenuated tgev, or porcine respiratory coronavirus (prcv), 3 antigenically related porcine coronaviruses with distinct enteric and respiratory tissue tropisms. mononuclear cells were prepared from mesenteric lymph nodes (mln), bronchial lymph nodes (bln), and spleens of pigs and tested for virus-specific responses ... | 1994 | 8017695 |
| mouse hepatitis virus gene 5b protein is a new virion envelope protein. | highly purified radiolabeled mouse hepatitis virus (mhv) a59 contained a previously overlooked protein which coelectrophoreses with the gene 5b product immunoprecipitated from infected cells. the gene 5b protein is post-translationally acylated. rabbit antibody raised against a recombinant gene 5b protein expressed in escherichia coli neutralized viral infectivity in the presence of complement, although not in the absence of complement. immunofluorescent staining of mhv-infected cells with two a ... | 1994 | 8030202 |
| simulation of the economic impact of transmissible gastroenteritis on commercial pig production in australia. | a simulation model (auspig) was used to predict the effect of an increase in piglet deaths, and a reduction in growth rate and an increase in feed conversion ratio of grower pigs on the profitability of two herds representative of the australian pig industry caused by the introduction of transmissible gastroenteritis virus (tge) into those herds. for each herd, mortality rates for piglets under 1 week of age of 50% and 95% were assumed to represent a 'moderate' and a 'severe' outbreak, respectiv ... | 1994 | 8067950 |
| identification of a putative cellular receptor for bovine herpesvirus 1. | recognition of a host cell receptor by a virus is the first and perhaps the most crucial step in initiating the disease process. this study was undertaken to identify the cellular receptor(s) for bovine herpesvirus 1 (bhv-1). previously, we reported the development and characterization of bovine anti-idiotypic antibodies (anti-ids) that induce neutralizing antibodies to bhv-1. these anti-ids inhibit bhv-1 penetration of permissive cells. we have used these anti-ids, which mimic an epitope on the ... | 1994 | 8077928 |
| coronavirus m proteins accumulate in the golgi complex beyond the site of virion budding. | the prevailing hypothesis is that the intracellular site of budding of coronaviruses is determined by the localization of its membrane protein m (previously called e1). we tested this by analyzing the site of budding of four different coronaviruses in relation to the intracellular localization of their m proteins. mouse hepatitis virus (mhv) and infectious bronchitis virus (ibv) grown in sac(-) cells, and feline infectious peritonitis virus (fipv) and transmissible gastroenteritis virus (tgev) g ... | 1994 | 8083990 |
| coronavirus immunogens. | coronaviruses (cv) infect a variety of livestock, poultry and companion animals. they belong to at least five antigenic groups. cv cause localized infections of the respiratory and/or intestinal tracts, with the exception of feline infectious peritonitis virus (fipv) and hemagglutinating encephalomyelitis (hev) which cause systemic infections. the enteropathogenic cv infect the villous enterocytes resulting in villous atrophy leading to malabsorptive diarrhea. several cv (bovine cv-bcv, porcine ... | 1993 | 8116187 |
| immunization of pregnant gilts with prcv induces lactogenic immunity for protection of nursing piglets from challenge with tgev. | the level of passive protection against transmissible gastroenteritis virus (tgev) was evaluated by experimentally infecting 12 pregnant gilts with different doses of porcine respiratory coronavirus (prcv) and challenging their litters at 4 days of age. an overall survival rate of 70% was found for piglets nursing the 12 prcv-infected gilts, compared to a 16% survival rate for piglets of nine uninfected control gilts. six of the prcv-infected gilts had adequate levels of immunity to resist infec ... | 1993 | 8128601 |
| mhv-a59 fusion mutants are attenuated and display altered hepatotropism. | mouse hepatitis virus strain a59 causes a persistent productive, but nonlytic, infection of cultured glial cells. we have mutants isolated from persistently infected glial cell cultures which have been shown to be fusion-defective due to a histidine to aspartic acid mutation (h716d) near the cleavage site of the peplomer protein, s. here, we examine the pathogenicity of these mutants and show differences in hepatotropism and virulence compared to wild-type virus (wt). two mutants chosen for deta ... | 1994 | 8128613 |
| coronavirus transmissible gastroenteritis virus-mediated induction of ifn alpha-mrna in porcine leukocytes requires prior synthesis of soluble proteins. | we studied the expression of interferon alpha (ifn alpha)-mrna in porcine non-adherent peripheral blood mononuclear cells (pbmc) after induction by the coronavirus transmissible gastroenteritis virus (tgev). we found that protein synthesis inhibition by cycloheximide (chx) blocked ifn alpha-mrna expression, except when pbmc were preincubated with a conditioned medium as a potential source of cytokines. these data indicate that ifn alpha-mrna induction by tgev requires de novo synthesis of protei ... | 1994 | 8142954 |
| contribution of antibody-secreting cells induced in mucosal lymphoid tissues of pigs inoculated with respiratory or enteric strains of coronavirus to immunity against enteric coronavirus challenge. | two antigenically related porcine coronaviruses, transmissible gastroenteritis virus (tgev) which infects primarily the intestinal tract and causes severe diarrhea, and porcine respiratory coronavirus (prcv) which infects the respiratory tract and causes subclinical or mild respiratory infections, presented a unique opportunity to study the interrelationship of gut-(galt) and bronchus-associated lymphoid tissues (balt) and their contribution to protective immunity against tgev infection. pigs we ... | 1994 | 8144965 |
| sequence of the spike protein of the porcine epidemic diarrhoea virus. | the complete sequence of the spike (s) gene of the br1/87 isolate of porcine epidemic diarrhoea virus (pedv) was determined from cdna clones. the predicted polypeptide was 1383 amino acids long, contained 29 potential n-linked glycosylation sites and showed structural features similar to those of the coronavirus spike protein. the pedv s protein, like that of the members of the transmissible gastroenteritis virus (tgev)-related subset, lacks a proteolytic site to yield cleaved amino and carboxy ... | 1994 | 8176382 |
| genomic organization and expression of the 3' end of the canine and feline enteric coronaviruses. | the genomic organization at the 3' end of canine coronavirus (ccv) and feline enteric coronavirus (fecv) was determined by sequence analysis and compared to that of feline infectious peritonitis virus (fipv) and transmissible gastroenteritis virus (tgev) of swine. comparison of the latter two has previously revealed an extra open reading frame (orf) at the 3' end of the fipv genome, lacking in tgev, now designated orf 6b. both ccv and fecv possess 6b-related orfs. the ccv orf 6b is colinear with ... | 1993 | 8209715 |
| molecular mimicry between s peplomer proteins of coronaviruses (mhv, bcv, tgev and ibv) and fc receptor. | in previous studies we have demonstrated molecular mimicry between the s peplomer protein of mouse hepatitis virus (mhv) and fc gamma receptor (fc gamma r) of igg. rabbit igg, but not its f(ab')2 fragments, monoclonal rat and mouse igg and the rat 2.4g2 anti-mouse fc gamma r monoclonal antibody (mab) immunoprecipitated natural and recombinant mhv s protein. on the basis of a number of criteria, mhv s peplomer protein exhibits fc igg binding ability. we report here a molecular mimicry between the ... | 1993 | 8209728 |
| genomic organisation of a virulent taiwanese strain of transmissible gastroenteritis virus. | transmissible gastroenteritis (tge) infection causes 65% of infectious piglet diarrhoea in taiwan. a virulent taiwanese strain, tfi, of transmissible gastroenteritis virus (tgev) from a field outbreak was isolated in cell culture and plaque purified. phenotypic differences were observed in the ability of tfi to infect certain cell lines. tgev strains tlm-83 (prcv belgium), to-163 (tgev japan) and purdue-115 (tgev usa) infected both st (swine testis) and rptg (pig kidney) cell lines whereas tfi i ... | 1993 | 8209736 |
| the use of pcr genome mapping for the characterisation of tgev strains. | previous studies on different transmissible gastroenteritis virus (tgev) strains, including porcine respiratory coronavirus (prcv), have identified regions within the genome that are polymorphic as regards insertions and deletions. for example the 672 base deletion within the s gene and multiple deletions 5', within and 3' of the orf-3a gene were detected in strains of prcv. the presence of deletions may be associated with a change in the virulence, attenuation or tissue tropism of the isolate. ... | 1993 | 8209745 |