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S Kit

Publications and source records attributed to S Kit.

At least 19 recordsLinked to original sources
PubMed1999

Diet fat and oral insulin-like growth factor influence the membrane fatty acid composition of suckling rat small intestine.

BACKGROUND: Insulin-like growth factor- plays an important role in small intestine development. The presence of insulin-like growth factor-1 and the complexity of the fatty acid composition in breast milk suggests that intestinal development may be influenced by manipulating the levels of these components. METHODS: To determine whether a physiological dose of insulin-like growth factor-1 would influence sucrase and lactase activity levels, 10-day-old suckling rat pups were treated with an oral gavage of insulin-like growth factor-1. Four diets differing in fat composition were fed to lactating dams. Brush border membranes were isolated from jejunal and ileal segments of suckling rat small intestine. Fatty acid analysis of choline and ethanolamine phospholipids was performed. RESULTS: Insulin-like growth factor-1 was found to have no effect on the sucrase and lactase activities of suckling rats. Changes in the diet fat composition of the mother's diet indirectly influenced the fatty acid composition of suckling rat small intestine. Insulin-like growth factor-1 decreased ileal C20:4n-6 levels. A correlation was observed between lactase activity and C20:4n-6 and C22:6n-3 levels. As C20:4n-6 levels increased, lactase activity appeared to decline. Increased lactase activity was observed when C22:6n-3 levels increased. CONCLUSIONS: The changes observed in C20:4n-6 levels in response to oral insulin-like growth factor-1, combined with the apparent trend of increased lactase activity with declining levels of C20:4n-6, may be of significance in the development of the small intestine in early life.

Animals↗
PubMed1997

A quantitative study of the efficacy of a deletion mutant bovine herpesvirus-1 differential vaccine in reducing the establishment of latency by wildtype virus.

Using quantitative polymerase chain reaction (PCR) we have studied the latency established by wildtype (WT) bovine herpesvirus-1 (BHV-1) after challenge of cattle that had been vaccinated with a double deletion (gC-/tk-) mutant BHV-1 vaccine. Fourteen animals were vaccinated intramuscularly with 2 ml containing 10(7.4) CCID50 (cell culture infectious dose 50%) of IBRV (NG) dltkdlgC and challenged, along with six unvaccinated control animals, 30 days later with 10(8.2) CCID50 of WT BHV-1 (Cooper). The ability of this vaccine to prevent acute clinical BHV-1 infection after this challenge has been previously reported. Sixty days after challenge, eight of the vaccinates and the six control animals were euthanitized and the trigeminal ganglia (TG) examined for the amount of WT BHV-1 DNA by an internal standard quantitative PCR. The quantitative protocol that we used is based on co-amplification of BHV-1 gC specific sequences (present in WT BHV-1 but absent in the vaccine strain) and sequences from the bovine growth hormone (BGH) gene, which is used as an internal standard. The TG of the eight vaccinates contained BHV-1 WT DNA, but in a statistically significantly lower amount than the unvaccinated controls. These results are significant from the standpoint that, to our knowledge, this is the first report of a systematic quantitative approach to the study of the effect of BHV-1 vaccines on latency. This technique could be used to measure and compare the efficiency of various BHV-1 vaccines in preventing or diminishing latency, which is a significant factor for the perpetuation of BHV-1 in cattle populations.

Animals↗
PubMed1994

Vaccination of newborn pigs in the presence of low levels of pseudorabies colostral antibodies.

To test the hypothesis that newborn pigs with pseudorabies virus (PRV) colostral antibodies might be actively immunized with a PRV glycoprotein gIII-deleted vaccine (Omnimark-PRV), 23 piglets were obtained from four sows that had been immunized 4 weeks and 2 weeks before farrowing with this vaccine. Thirteen piglets were immunized with Omnimark-PRV when they were less than 3 days old and ten piglets served as non-vaccinated controls. Piglets were weaned at 28 days of age and challenged with virulent PRV (Shope) when they were 49 days old, at which time the vaccinated and control pigs were seronegative for PRV virus neutralizing (VN) and gIII antibodies, and all control pigs and ten vaccinees were seronegative for PRV antibodies by the latex agglutination test (LAT). Two vaccinees were LAT(+) and one was LAT(+/-). Central nervous system signs and/or respiratory disease signs were observed in six of ten control pigs with the death of one control, while two of 13 vaccinees showed only very mild and transient clinical disease signs and there were no fatalities. Non-vaccinees lost weight until postchallenge day (PCD) 6 and did not regain prechallenge weight until PCD 8. All vaccinees gained weight after challenge and at PCD 11 had mean weight gains nearly twice that of the controls. On PCD 11, the geometric mean titre for VN antibodies of non-vaccinees was 9.3, while that of vaccinees was 49.0, indicating that the vaccinated group had been immunologically primed.

Animals↗
PubMed1994

Development of active immunity in newborn pigs with colostral antibodies by vaccination with gIII-deleted PRV.

Maternal antibodies interfere with active immunization of swine by gI-deleted pseudorabies virus [(PRV); Aujeszky's disease virus] vaccines. To test the hypothesis that modified-live (MLV) vaccines retaining the PRV gI and with deletions in the PRV glycoprotein gIII and thymidine kinase (TK) genes might be efficacious in circumventing colostral antibody interference, the OMNI-MARK-PRV (gI+ gIII- TK-) vaccine was administered intramuscularly to 13 newborn pigs with colostral antibodies, while 10 pigs from the same litters served as nonvaccinated controls. At 49 days of age, when PRV virus neutralization (VN) antibodies were negative and all nonvaccinated pigs as well as 10 vaccinates were latex agglutination test (LAT)-negative, the pigs were challenged intranasally with the virulent PRV(SHOPE) strain. In support of the hypothesis, it was found that several central nervous system and respiratory disease signs developed in 6 of 10 nonvaccinates, with one fatality, while 2 of 13 vaccinates showed only very mild and transient disease signs. Nonvaccinates lost weight until post challenge day (PCD) 6, did not regain prechallenge weight until PCD 8, and at PCD 11 had gained only 4.9 pounds/pig. Vaccinates gained weight after challenge and at PCD 11 showed a 9.4 pounds/pig weight gain. On PCD 11, the geometric mean titer (GMT) for VN antibodies of the nonvaccinates was 9.3, while the GMT of the vaccinates for VN antibodies was 49.0, showing that vaccinated pigs had been immunologically primed.

Animals↗
PubMed1993

Circumvention of maternal antibody interference by immunization of newborn pigs with glycoprotein gIII-deleted marker vaccine.

Maternal antibodies interfere with the immunization of swine by modified live-virus pseudorabies virus (PRV) vaccines. To test the hypothesis that a PRV vaccine attenuated by deletions in the thymidine kinase (TK) and gIII genes might reduce interference by maternal antibodies, pigs with moderate to low levels of colostral PRV antibodies were immunized with the TK- gIII-OMNIMARK-PRV vaccine. Vaccinates and non-vaccinates were challenged intranasally with virulent PRV at 7 weeks of age. In support of the hypothesis, it was found that central nervous system (CNS) and/or respiratory disease developed in six out of 10 controls with a fatal outcome in one, while two out of 13 vaccinates showed only very mild and transient CNS or respiratory disease signs with no fatalities. All vaccinates gained weight while non-vaccinates initally lost weight. At post-challenge day (PCD) 11, vaccinates showed 4.5 lb/pig greater weight gain than non-vaccinates. Virus neutralization (VN) analyses before and after challenge showed that vaccinates had been primed immunologically. In another experiment, newborn pigs from a pseudorabies disease-quarantined herd with high VN antibody titres were vaccinated, respectively, with the gIII-TK-OMNIMARK-PRV vaccine, a TK-gI-gX-vaccine, or no vaccine and challenged with virulent PRV at 14 weeks of age when VN titres were < 1:2. By PCD 9, the TK-gIII-group had outgained the TK-gI-gX- and the control groups, respectively, by 6.0 and 3.2 lb per pig.

Animals↗
PubMed1993

Efficacy of a deletion mutant bovine herpesvirus-1 (BHV-1) vaccine that allows serologic differentiation of vaccinated from naturally infected animals.

Fifteen bovine herpesvirus-1 (BHV-1)-negative calves were vaccinated intramuscularly with 10(7.4) plaque-forming units of a double-deletion BHV-1 mutant (IBRV(NG)dltkdlgIII), and 6 remained as nonvaccinated controls. Thirty days after vaccination, the animals were challenged by nasal instillation of 10(8.2) CCID50 of a virulent BHV-1 strain (Cooper). The vaccinated calves were protected against wildtype virus challenge as demonstrated by clinical evaluation. Most of the vaccinates developed only a mild rhinitis (lasting an average of 6.5 days) with almost no systemic symptoms, whereas the controls developed a serious illness characterized by rhinitis (mean = 11.5 days), conjunctivitis, hyperthermia, apathy, loss of appetite, and dyspnea. The vaccinates also shed significantly less virus and for a shorter period of time (mean = 5.5 days) than the controls (mean = 9 days). Thirty days after vaccination, the vaccinates were negative in an anti-gIII specific blocking enzyme-linked immunosorbent assay (ELISA), despite the fact that most of them had developed neutralizing antibodies (serum neutralization titers ranging from 1:2 to 1:16). Seroconversion to gIII was detected as early as 7 days postinfection (dpi). Fourteen days after the challenge, all the animals exposed to wildtype BHV-1 had developed anti-gIII antibodies and were positive in this differential serologic test. Six controls plus 8 vaccinates kept in isolation were still positive to gIII when tested at 75 dpi. The use of the IBRV(NG)dltkdlgIII strain in conjunction with an anti-gIII specific blocking ELISA kit represents a powerful tool for BHV-1 control/eradication programs.

Animals↗
PubMed1992

Expression of porcine pseudorabies virus genes by a bovine herpesvirus-1 (infectious bovine rhinotracheitis virus) vector.

Recombinant DNA techniques were used to insert foreign genes into bovine herpesvirus-1 [infectious bovine rhinotracheitis virus (IBRV)] vectors which were attenuated by deletion and/or insertion mutations in the IBRV thymidine kinase (tk) gene. In one recombinant, the regulatory and coding sequences of the late pseudorabies virus (PRV) glycoprotein gIII gene, were inserted into the early IBRV tk gene. This recombinant efficiently expressed the PRV gIII gene indicating that immediate early IBRV proteins were competent to transactivate the late PRV gIII gene. IBRV vector viruses were also prepared in which the coding sequences of the early PRV tk gene, the late PRV gIII gene, and the E. coli beta-galactosidase gene were ligated to the late IBRV gIII promoter. Genotypes and phenotypes of the recombinant viruses were verified by restriction endonuclease and molecular hybridization experiments, thymidine plaque autoradiography, beta-gal plaque assays, and by immunoprecipitation experiments on extracts from 3H-mannose-labelled cells. The recombinant IBRV expressing beta-gal from the IBRV gIII promoter has been useful as an intermediate in the construction of IBRV vectors harboring foreign DNA sequences. The infectivity of the IBRV recombinant that expressed PRV gIII from the IBRV gIII promoter, was neutralized by polyclonal PRV antisera and by monoclonal antibodies to PRV gIII. The PRV gIII glycoprotein synthesized by the preceding recombinant has been used to coat microtiter test plate wells in a PRV gIII differential diagnostic test kit.

Animals↗
PubMed1992

Blocking ELISA for distinguishing infectious bovine rhinotracheitis virus (IBRV)-infected animals from those vaccinated with a gene-deleted marker vaccine.

A sensitive and specific blocking enzyme-linked immunosorbent assay (ELISA) was developed to distinguish infectious bovine rhinotracheitis virus (IBRV)-infected animals from those immunized with a glycoprotein gIII deletion mutant, IBRV(NG)dltkdlgIII. For this ELISA, undiluted test sera are used to block the binding of an anti-IBRV gIII monoclonal antibody (mAbgIII)-horseradish peroxidase (HRPO) conjugate to gIII antigen. TMB substrate is used for color development. Negative S/N values (defined as the absorbance at 650 nm of test sera/absorbance at 650 nm of negative control sera) of > 0.80 were obtained with immune sera from gnotobiotic cattle immunized with several bovine viruses, with bovine antisera to bovine herpesvirus-2, and vesicular stomatitis virus, with porcine antisera to pseudorabies virus and parvovirus, and with normal sera from heterologous species. Negative S/N values were also obtained with sera from rabbits twice vaccinated with IBRV(NG)dltkdlgIII. However, the S/N values became positive (S/N < 0.8) 10 to 17 days after the rabbits were challenge exposed to virulent IBRV(Cooper). Most of 116 sera (84%) from feedlot cattle with virus neutralization (VN) titers of < 1:2 or < 1:4 had negative S/N values > 0.8, but 18 sera with negative VN titers had positive S/N values, consistent with observations indicating that an IBRV outbreak was occurring in one of the feedlot herds. Thirty nine sera (98%) from feedlot cattle with VN titers of 1:2 to 1:128 had positive S/N values (< 0.8). One serum with a VN titer of 1:2 had a borderline (+/-) S/N value of 0.81. After immunization with a commercial gIII-positive IBRV vaccine, 115/116 sera with VN titers of 1:2 to 1:256 had positive S/N values (< 0.8). One serum with a VN titer of 1:2 had a negative S/N value of 0.83. Serum from one vaccinated animal that failed to seroconvert after vaccination (VN < 1:4) showed a strongly positive ELISA S/N of 0.48.

Animals↗
PubMed1991

Modified-live infectious bovine rhinotracheitis virus vaccine expressing monomer and dimer forms of foot-and-mouth disease capsid protein epitopes on surface of hybrid virus particles.

Modified-live, attenuated infectious bovine rhinotracheitis (IBR) hybrid virus vaccines have been constructed by inserting in the major IBRV glycoprotein gIII gene chemically synthesized deoxyribonucleotide sequences encoding the bovine growth hormone signal sequence and monomeric or dimeric forms of the foot and mouth disease virus (FMDV) VP 1 epitope sequences. The foreign DNA sequences were inserted at the N-terminal end of the IBRV gIII coding sequence and were driven by the IBRV gIII promoter. The sequences encoding the first 38 and the first 21 amino acids of the IBRV gIII were deleted from the hybrid viruses containing inserts of the monomeric and dimeric FMDV epitope sequences, respectively, to avoid redundant signal sequences. Plaque immunoassay experiments with guinea pig and bovine anti-FMDV peptide antisera, and with anti-IBRV gIII monoclonal antibodies demonstrated that IBRV-FMDV fusion proteins were expressed in virus-infected MDBK cells. Immunoelectron microscopy analyses demonstrated that the IBRV-FMDV fusion proteins were expressed as repeated structures on the surface of virus particles. Experiments showed that the recombinant IBRV-FMDV viruses protected cattle from IBRV (Cooper) challenge and induced anti-FMDV peptide antibodies, thereby demonstrating that the FMDV epitopes were expressed in vivo.

Amino Acid Sequence↗
PubMed1991

Bovine herpesvirus-1 (infectious bovine rhinotracheitis virus)-based viral vector which expresses foot-and-mouth disease epitopes.

A recombinant infectious bovine rhinotracheitis virus (IBRV) vector has been constructed to express bovine growth hormone signal sequence plus a foot-and-mouth disease virus [FMDV (O1K)] capsid protein (VP1) epitope as the N-terminal sequence of an IBRV glycoprotein gIII fusion protein on the surface of virus infected cells and on the surface of virus particles. Sequences encoding the first 38 amino acids of IBRV gIII were deleted from the recombinant to avoid redundant glycoprotein signal sequences, but IBRV gIII epitopes detected by anti-gIII monoclonal antibodies were retained. Phenotypes were confirmed by in situ immunostaining of virus plaques with anti-FMDV peptide sera, by immunogold staining of permeabilized- and non-permeabilized infected cells, and by virus neutralization experiments with anti-FMDV peptide sera. Vaccination with the IBRV-FMDV recombinant induced protective levels of anti-FMDV antibodies in calves and protected them from challenge with virulent IBRV.

Amino Acid Sequence↗
PubMed1991

Sensitive glycoprotein gIII blocking ELISA to distinguish between pseudorabies (Aujeszky's disease)-infected and vaccinated pigs.

A blocking enzyme-linked immunosorbent assay (ELISA) test has been developed to distinguish pseudorabies virus (PRV) (Aujeszky's disease virus) -infected pigs from those immunized with a glycoprotein g92 (gIII) deletion mutant, PRV (dlg92dltk) [OMNIMARK-PRV]. This blocking ELISA test utilizes an anti-PRV gIII monoclonal antibody (mAbgIII)-horseradish peroxidase (HRPO) conjugate, TMB for color development and a cloned PRVg92 (gIII) antigen to coat wells of microtiter test plates. Undiluted sera are used to block the binding of the mAbgIII-HRPO conjugate to the antigen. The gIII blocking ELISA is specific and has a sensitivity comparable to screening ELISA and latex agglutination tests. PRV-negative sera and sera from pigs vaccinated once, twice, or four times with the gIII-negative vaccine all showed negative S/N values of greater than 0.70 (S/N defined as the optical density at 630 nm of test sera/optical density at 630 nm of negative control sera). Sera from PRV-infected herds, sera from pigs experimentally infected with virulent PRV, and sera from pigs vaccinated with modified-live or inactivated gIII+ vaccines were positive for gIII antibodies (S/N less than 0.7). Sera from pigs experimentally infected with 200 PFU virulent PRV seroconverted to gIII+ antibodies 7-10 days postinfection. Sera from pigs vaccinated with gpX- and gI- vaccines seroconverted to gIII+ antibodies 7-8 days after vaccination. The gIII antibodies persisted after gIII+ vaccinated for at least 376 days postvaccination. Sera from pigs protected by vaccination with PRV (dlg92dltk) and then challenge exposed to virulent PRV at 21 days postvaccination showed gIII+ antibodies by 14 days postchallenge. The specificity and sensitivity of the gIII blocking ELISA assay was further demonstrated on the United States Department of Agriculture-National Veterinary Services Laboratory (USDA-NVSL) sera from the 1988 PRV check set and the 1989 gIII PRV check set by comparing the gIII blocking ELISA assay with virus neutralization, screening/verification ELISA and latex agglutination assays.

Animals↗
PubMed1990

Genetically engineered vaccines for control of Aujeszky's disease (pseudorabies).

A gene-deleted pseudorabies (PR) (Aujeszky's disease) vaccine, named OMNIVAC-PRV, was licensed by the United States Department of Agriculture-Animal and Plant Health Inspection Service (USDA-APHIS) on January 16, 1986, the first recombinant DNA-derived modified-live virus vaccine to be licensed for manufacture and sale anywhere in the world. Two months later, a second generation gene-deleted 'marker' vaccine, OMNIMARK-PRV, was described. Surprisingly, these landmark applications of genetic engineering to vaccine development triggered a brouhaha and a lawsuit (ultimately dismissed by Federal District Court Judge Thomas Hogan) as well as a Congressional Hearing on the adequacy of USDA regulatory procedures for the licensing of supposedly 'dangerous' recombinant DNA-derived products. Thus, its is rather gratifying that only 4 years later, a consensus of government, industry, veterinarians and the scientific community has developed, affirming that the recombinant DNA-derived vaccines were in fact a major breakthrough for pseudorabies (PR) control and eradication, and that without the advantages of gene-deleted vaccines, plans for PR eradication would not be practical.

Animals↗
PubMed1990

Herpes simplex virus type 2 meningoencephalitis resistant to acyclovir in a patient with AIDS.

A case is reported of relapsing fatal meningoencephalitis caused by a neurovirulent thymidine kinase-positive (TK+) type 2 herpes simplex virus (HSV) that developed thymidine kinase deficiency (TK-) during intravenous acyclovir therapy. A patient with AIDS was admitted for acyclovir treatment of a persistent perirectal herpetic ulcer. He subsequently developed meningoencephalitis. A TK+ type 2 HSV was isolated from a brain biopsy specimen. A progressive and fatal relapse occurred, and a TK- type 2 HSV was isolated from his cerebrospinal fluid. Restriction endonuclease analysis of viral DNA from perianal, brain, and cerebrospinal fluid isolates were similar, suggesting that they were the same viral strain. Animal virulence studies indicated significant cutaneous virulence in immunocompromised mice models for the TK- isolates. This case is notable because TK- HSV have, in the past, lacked neurovirulence and because acyclovir resistance developed during therapy and caused the patient's death.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Blocking ELISA to distinguish pseudorabies virus-infected pigs from those vaccinated with a glycoprotein gIII deletion mutant.

A blocking enzyme-linked immunosorbent assay (ELISA) test has been developed to distinguish pseudorabies virus (PRV)-infected pigs from those immunized with a glycoprotein g92(gIII) deletion mutant, PRV(dlg92dltk). The blocking ELISA utilizes 96-well microtiter test plates coated with a cloned PRV g92(gIII) antigen, a mouse monoclonal antibody against gIII antigen (moMCAgIII): horseradish peroxidase (HRPO) conjugate, and undiluted test sera. Analyses can be completed in less than 3 hours with results printed out by an automated plate reader. Analyses on over 300 pig sera from PRV-free farms, on sera from other species, and on control sera containing antibodies to microorganisms other than PRV showed that the ratio of the optical density at 405 nm for the test sample to the optical density at 405 nm for the negative control (S/N value) was greater than 0.7 for all sera. No false positives were identified. Likewise, the S/N values were greater than 0.7 for over 400 sera obtained from pigs vaccinated twice with more than 1,000 times the standard PRV (dlg92dltk) dose or 1-4 times with the standard dose (2 x 10(5) TCID50/pig). Following challenge exposure to virulent PRV, the S/N values of the vaccinates were 0.1, showing that g92(gIII) antibodies in the sera of experimentally challenged pigs strongly blocked the binding of the moMCAgIII:HRPO conjugate to the antigen-coated wells. Sera of 233 pigs from PRV-infected herds with virus neutralization (VN) titers of 1:4 or greater were tested. All except 2 of these sera had S/N values less than 0.7 and more than 175 had S/N values less than 0.1. Sixteen sera from fetal pigs with VN titers of 1:4 or greater had S/N values of 0.24 or less, but 2 sera with VN titers of 1:4 when tested 5 years prior to the PRV g92(gIII) blocking ELISA test gave false negative S/N values. Twenty-four of 29 pig sera from PRV-infected herds with VN titers less than 1:4 were positive for g92(gIII) antibodies, illustrating the sensitivity of the PRV g92(gIII) blocking ELISA test. Analyses on 7 sera with VN titers of 1:4-1:64 showed that titers obtained with the PRV g92(gIII) blocking ELISA test were from 2- to 16-fold greater than the VN titers. The accuracy and sensitivity of the PRV g92(gIII) blocking ELISA test was further demonstrated by analyses of 40 unknown sera supplied in the National Veterinary Services Laboratories 1988 PRV check test kit.

Animals↗