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PubMed1987

Antigenic variation of caprine arthritis-encephalitis virus during persistent infection of goats.

Six caprine arthritis-encephalitis virus (CAEV)-free goats kept in strict isolation were inoculated intravenously with a cloned CAEV isolate (virus 020). At 78 weeks post-infection a virus (virus 095) isolated from one of the goats was shown to have the characteristics of CAEV, but was antigenically distinct from virus 020 and two other CAEV isolates by serum neutralization tests. Serum from the goat that had the variant virus neutralized the inoculum virus and the variant virus but serum from other inoculated goats neutralized only the inoculum virus. The variant virus and the inoculum virus were shown to co-exist in the infected goat, but the presence of the antigenic variant did not appear to be associated with an increase in severity of lesions compared with other inoculated goats.

Animals↗
PubMed1990

Neutralization of bovine herpesvirus type 4 by pairs of monoclonal antibodies raised against two glycoproteins and identification of antigenic determinants involved in neutralization.

In infected cattle, bovine herpesvirus type 4 (BHV-4) induces an immune response with low neutralizing antibody levels or in the absence of such antibodies. For the study of this phenomenon, monoclonal antibodies (MAbs) raised against two BHV-4 glycoproteins identified previously (150K/120K/51K and 120K/16.5K) were used in neutralization tests. None of the MAbs except for MAb 16 could neutralize alone; pairs of MAbs against the 150K/120K/51K and 120K/16.5K glycoproteins were able to neutralize BHV-4 infectivity. MAbs involved in neutralization were used in competitive binding assays to identify epitopes relevant for BHV-4 neutralization. These MAbs showed a low avidity and a weak neutralizing activity, and they partially decreased BHV-4 attachment to cells. These results suggest that the BHV-4 glycoprotein domains involved in viral infectivity are poorly exposed to the immune system.

Animals↗
PubMed1991

Japanese encephalitis virus fusion protein with protein A expressed in Escherichia coli confers protective immunity in mice.

A complementary DNA (cDNA) that codes C-terminal, one-third of envelope glycoprotein (E) and N-terminal 65 amino acids of NS1 protein of Japanese encephalitis (JE) virus was inserted into Escherichia coli expression vector pRIT2T. The inserted gene was expressed as a fusion protein with protein A, and the expressed protein was intraperitoneally injected into mice. The immunized mice produced anti-JE antibodies measured by the hemagglutination-inhibition and neutralization tests as well as ELISA and were protected from the lethal challenge of JE virus by intraperitoneal inoculation.

Animals↗
PubMed1994

Haemolytic activity associated with parasporal inclusion proteins of mosquito-specific Bacillus thuringiensis soil isolates: a comparative neutralization study.

Solubilized parasporal inclusions of the three mosquito-specific Bacillus thuringiensis isolates belonging to three different H serovars, co-isolated from a single soil microhabitat, showed haemolytic activity towards mammalian erythrocytes. Neutralization tests with antibodies against whole inclusion proteins resulted in crossed neutralization of haemolytic activity among the isolates and the type strain of B. thuringiensis serovar kyushuensis, indicating that the three soil isolates produce toxins related to the CytB toxin. No cross-neutralization occurred between the type strain of B. thuringiensis serovar israelensis and the three soil isolates.

Animals↗
PubMed1968

Examination by chromatography and immunodiffusion of an adenovirus 3 isolated from humans with infectious hepatitis.

Prototype adenovirus 3 and adenovirus SC8, which was found in feces from a patient with infectious hepatitis and which was classified as adenovirus 3 by standard procedures, were compared by chromatography and immunodiffusion techniques. When the radioactive adenovirus moiety in SC8 had been separated from other radioactive components of tissue culture by gel filtration, a smaller infectious agent was detected, whereas with prototype adenovirus 3 one infectious agent was found. The large agent from SC8 was classified as adenovirus type 3 by serum neutralization tests, but results from homologous and heterologous immunodiffusion tests and heat sensitivity tests indicated that this agent was different from the classical prototype adenovirus 3. Similar precipitin patterns obtained in homologous and heterologous reactions by immunodiffusion suggested a similarity between the smaller particle and an unidentified agent isolated without adenoviruses from blood clots from overt cases of hepatitis. With the present evidence, it was not possible to relate the smaller agent to adeno-associated viruses; however, its similarity to an agent isolated from blood of overt cases implies a possible relationship with hepatitis. The continued recovery of the variant strain of adenovirus type 3 from patients with hepatitis, although at relatively low rates of isolation, suggested a possible undetermined relation to the disease.

Adenoviridae↗
PubMed1991

Intermediate human adenovirus type 22/H10,19,37 as a new etiological agent of conjunctivitis.

Eight strains of a new intermediate adenovirus were isolated in the course of an investigation of conjunctivitis in Hiroshima City, Japan. The strain was first isolated in July 1986. All eight strains were isolated from conjunctival swab samples from patients with conjunctivitis, mainly epidemic keratoconjunctivitis. The virus was typed as adenovirus type 22 in neutralization tests and was related closely to types 10, 19, and 37 in hemagglutination inhibition tests. The DNA cleavage patterns of the eight strains with nine restriction endonucleases were the same with one exception but different from those of the above serologically related species. We conclude that the intermediate adenovirus is a new etiological agent of conjunctivitis, mainly epidemic keratoconjunctivitis.

Adenoviruses, Human↗
PubMed2004

Evidence of an antigenic shift among Palyam serogroup orbiviruses.

The Japanese isolates of Palyam serogroup viruses isolated from 1985 to 2001 were investigated for the genome sequence of segments 2 and 7 and were phylogenetically analyzed in comparison with Australian and African isolates of the same serogroup. The nucleotide sequences of segment 7 were highly conserved within Japanese isolates (95.1 to 100%) and between Japanese and Taiwanese isolates (96.0 to 100%), whereas the identities between Japanese and Taiwanese isolates and Australian and African isolates were fairly conserved (84.2 to 92.0%). Phylogenetic analysis based on segment 7 revealed three clusters according to geographical origin. As a result of the nucleotide sequence analysis of segment 2, which encodes a serotype-specific antigen, Japanese isolates were classified into two groups by genome length and nucleotide identities. Four of the nine Japanese isolates were categorized into the same group as prototype strain K-47 of the Chuzan virus, and the remaining isolates were categorized into the same group as the D'Aguilar virus and Nyabira virus. Phylogenetic analysis based on segment 2 revealed two clusters, the cluster containing Chuzan virus and the cluster containing the D'Aguilar and Nyabira viruses. To examine the antigenic relationship among viruses categorized in different clusters, we conducted a cross-neutralization test. KSB-29/E/01, isolated in 2001 in Japan, was neutralized by antiserum not only to strain B8112 of D'Aguilar virus but also to Chuzan virus. These results indicated that genetically and antigenically unique characteristics of KSB-29/E/01 were attributed to genetic reassortment of segment 2 between Chuzan virus and D'Aguilar virus.

Animals↗
PubMedDate not supplied

Isolation of two strains of West Nile virus during an outbreak in southern Russia, 1999.

From July to September 1999, a widespread outbreak of meningoencephalitis associated with West Nile virus (Flavivirus, Flaviviridae) occurred in southern Russia, with hundreds of cases and dozens of deaths. Two strains of West Nile virus isolated from patient serum and brain-tissue samples reacted in hemagglutination-inhibition and neutralization tests with patients' convalescent-phase sera and immune ascites fluid from other strains of West Nile virus.

Adolescent↗
PubMed1976

[Sensitivity and specificity of the passive hemagglutination reaction applied to titration of herpes antibodies].

52 human sera were checked for herpes virus hominis type 1 antibodies by passive hemagglutination, complement fixation, neutralization tests and plaque reduction in presence of complement. A good correlation was observed among the results obtained by the passive hemagglutination test and the plaque reduction in presence of complement. The rapidity of the indirect hemagglutination test and the sensitivity of the reaction are in favour of its routine use.

Antibodies, Viral↗
PubMedDate not supplied

Isolation of infectious bronchitis virus from intestine and reproductive organs of laying hens with dropped egg production.

A total of 52 samples (22 cloacal swabs and 30 pooled ovaries and oviducts) from hens with a history of a 25 to 40% drop in egg production from 30 flocks were examined for the isolation of infectious bronchitis virus in embryonated chicken eggs. Five isolates were obtained: three from cloacal swabs and two from reproductive organs. These isolates were identified and characterized on the basis of agar-gel-precipitation, hemagglutination, and neutralization tests and other physicochemical characteristics.

Animals↗
PubMed1988

Protective murine monoclonal antibodies to tetanus toxin.

Monoclonal antibodies against tetanus toxin were generated by fusion of mouse NS-1 myeloma cells with spleen cells from BALB/C mice immunized with tetanus toxoid. Twenty seven hybridomas against tetanus toxin were obtained. Six hybridoma clones, designated as 1A6B12, 1H7D9, 3A8G9, 3A9F2, 3F9H9, 4A6D11 were selected for further studies. All of them were IgG1, k chain and bound specifically to tetanus toxin and toxoid. All six clones were injected intraperitoneally into pristane-primed BALB/C mice. Antibodies with titer up to 10(6) were obtained in the ascites. Results obtained from in vivo neutralization test showed that 1A6B12, 3A8G9, 3F9H9, 4A6D11 mAbs did have neutralizing activities against tetanus toxin. Monoclonal antibody 4A6D11 had the strongest neutralizing activity. 4A6D11 were purified from ascites by DEAE-52 ion exchange chromatography. Comparing to U.S.A. standard antitetanus toxin antiserum, 50 micrograms purified 4A6D11 mAb had 1 international unit neutralizing activity. The purified 4A6D11 mAb was also coupled to cyanogen bromide-activated sepharose to make an affinity column. Pure tetanus toxin can be obtained by passing crude tetanus toxin through this column and eluting the adsorbed toxin with 4M urea. Large scale purified tetanus toxin could be obtained by this method.

Animals↗
PubMed1985

California serogroup virus infection in a horse with encephalitis.

A 4-fold or greater seroconversion to the snowshoe hare serotype of the California serogroup of viruses in a horse with acute encephalitis was demonstrated by hemagglutination-inhibition, complement-fixation, and neutralization tests. The horse had a mild fever, was ataxic, had a head tilt, and was observed to circle. Chloramphenicol, dexamethasone, and B complex vitamins were administered and the horse recovered. The snowshoe hare virus is a recognized human pathogen, but it has not been associated with disease in horses. It is unknown whether horses play a role as amplification hosts for the snowshoe hare virus in nature, and further studies appear indicated.

Animals↗
PubMed1971

A comparison of bluetongue virus and EHD virus: electronmicroscopy and serology.

Bluetongue virus, BT(8), and the virus of epizootic hemorrhagic disease (EHD) of deer, NJ-55, were plaque purified and compared electronmicroscopically and serologically. The latter included a plaque reduction neutralization test, the agar gel precipitin test, and the complement fixation test. The viruses were indistinguishable morphologically, but antigenically different. A plaquing technique was described for EHD virus.

Animals↗
PubMed1983

Powassan virus encephalitis resembling herpes simplex encephalitis.

A boy from New York traveling in Nova Scotia had olfactory hallucinations and other signs of temporal lobe involvement, leading to a diagnosis of herpes simplex encephalitis. The patient was treated with vidarabine and made a complete recovery. However, hemagglutination inhibition, complement fixation, and neutralization tests identified Powassan virus (POW) as the pathogen. Shortly before his trip to Nova Scotia, the patient had traveled in an area where POW encephalitis had occurred in humans (the eastern part of the state of New York), and he also came in contact with a known reservoir of POW infection (a groundhog) at home.

Child↗
PubMed1997

[Western blotting in the serologic diagnosis of enterovirus infections. II. Detection of coxsackievirus antibodies in the sera of patients with suspected enterovirus infection and in paired specimens of sera and saliva].

Detection of anti-Coxsackie virus antibodies in sera with suspect enterovirus infection by the Western blotting (WB) method revealed complete agreement of results with virus neutralization tests (VNT) in those patients where in the VNT no antibodies against any of the tested Coxsackie viruses were detected. Comparison of the results of WB and VNT in other patients did not rule out an inter-type cross-reaction. In paired specimens of sera and saliva comparable results were obtained by WB, VNT and the complement fixation method. The rapid and relatively simple character of the WB method makes this method suitable for more detailed elaboration and introduction into routine diagnosis of enterovirus infections.

Antibodies, Viral↗
PubMed1953

The 1952 outbreak of encephalitis in California; laboratory methods for etiologic diagnosis.

The general procedures used in the diagnosis of neurotropic viral diseases are outlined and are discussed with specific reference to western equine encephalitis. Cerebrospinal fluid is considered practically worthless as a starting material, in attempts to isolate the causal agent. The material of choice in attempting to recover the virus is central nervous system tissue, available only in instances of fatal infection. In the usual case, the diagnosis depends upon serologic or immunologic methods. These methods are aimed at detecting the presence of specific antibodies and of increases in the content of antibodies in the blood during the course of the illness. The in vitro complement fixation test is considered a better diagnostic tool than the in vivo neutralization test, since rises in titer are more readily detectable by the former technique than by the latter.

Animals↗
PubMed1972

A comparison of the antigens present on the surface of virus released artificially from chick cells infected with vaccinia virus, and cowpox virus and its white pock mutant.

Antisera prepared against vaccinia and cowpox viruses were absorbed with purified suspensions of vaccinia virus, red cowpox and white cowpox viruses. They were then tested for their ability to neutralize the viruses, and to precipitate the virus soluble antigens.The results showed that some virus specific antigens were not virus surface components and that some components were present on the surface of all three viruses. However, certain components were detected on the surface of vaccinia virus but not on the surface of cowpox virus, and vice versa. Some evidence for the existence of a vaccinia-specific surface component was also obtained.Comparisons between results of cross-neutralization tests and immunodiffusion tests on the absorbed sera indicated that antibody to a number of antigens, including the classical LS, and the cowpox-specific d antigen play no part in the process of poxvirus neutralization.

Animals↗
PubMed1976

Comparative sensitivities of radioimmunoassay, crossoverelectrophoresis, and agar gel immunodiffusion for HBAg detection.

The relative sensitivities of radioimmunoassay, crossoverelectrophoresis, and agar gel immunodiffusion for detecting HBAg in unconcentrated versus concentrated serum samples are compared and discussed. The sensitivities of the various immunologic methods were enhanced severalfold in concentrated serum samples. This is a fundamental consideration in designing a screening program for detecting HBAg and anti-HBAg antibody in hospital patients and donors. The authors propose that serum samples that have marginal reactions or low counts (RIA) be concentrated with Lyphogel or MiniconTM-125 concentrator and retested before test results are reported. Specificity of positive results was studied by neutralization tests with human serum containing antibodies to HBAg.

Antibodies, Viral↗