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PubMed1986

[Monoclonal antibodies to the Japanese encephalitis virus in ascitic hybridoma preparations].

Among 4 ascitic preparations of hybridomas producing monoclonal antibodies to the Japanese encephalitis virus (JE) hybridomas JE-4 and JE-19 had high multiplication potentials and high levels of reimplantation and transplantability in mice BALB/c. The possibility of using the complete Freund's adjuvant and pristan for priming the mice was shown. The use of pristan promoted a significant decrease in the periods of ascitic tumor development and an increase in accumulation of the cells in the ascitic tumor, in the volume of the ascitic fluid and the titers of the monoclonal antibodies. The serological assays revealed that the monoclonal antibodies produced by JE hybridomas did not react with the JE virus antigen in the hemagglutination inhibition test. However, they were highly active in the indirect immunofluorescence test. IgM of hybridoma JE-19 reacted with the JE virus antigen in the complement fixation test while monoclonal IgG produced by hybridoma JE-4 was active in the neutralization test when titrated in the cultures of the swine embryo kidney transplantable cells. The monoclonal JE antibodies did not react with the JE virus antigen in the hemagglutination inhibition test and did not bind to the antigen of the "Sofin" strain of the forest-spring encephalitis virus in the test performed with the indirect fluorescent antibody technique.

Animals↗
PubMed1990

Early diagnosis of enteroviral meningitis by a solid-phase reverse immunosorbent test and virus isolation.

45 cases of aseptic meningitis/meningoencephalitis were studied with regard to enteroviral etiology by virus isolation and solid-phase reverse immunosorbent test (SPRIST), a cross-reacting test for enterovirus IgM. An etiological diagnosis was reached in 37/45 (82%) patients. Etiological diagnoses other than enteroviruses were found in 8 patients: Borrelia burgdorferi in 4, varicella-zoster virus in 2, herpes simplex virus in 1 and mumps virus in 1 patient. Enteroviruses (echovirus 6, 21 and 30) were isolated from cerebrospinal fluid (CSF) in 26/37 (70%) and from stool samples of 20/21 (95%) of patients with no other etiology. Altogether enteroviruses were isolated from CSF and/or faecal samples in 29 patients. Echovirus 30 dominated as etiologic agent. In 34/40 (85%) of the samples with an enterovirus, a cytopathogenic effect was observed in cell culture within 4 days. In patients with an enterovirus isolate a SPRIST IgM response to echovirus 3, 5, 7 and/or coxsackievirus B3 was detected in 6/13 (46%) sera sampled 3-4 days after the onset of meningeal symptoms and in altogether 17/25 patients (68%). In 4 out of these virus isolation positive and SPRIST negative patients a single serum for SPRIST was available less than 4 days after onset of meningeal symptoms. Antigen from echovirus 5 gave the highest diagnostic yield. The SPRIST IgM test was positive in 2 cases where virus isolation, complement fixation and neutralization tests were negative. Epidemiological data however supported an enteroviral diagnosis in both of them. In conclusion, both SPRIST and virus isolation seem to be valuable for the early diagnosis of enteroviral meningitis.

Adolescent↗
PubMed1987

Herpes simplex virus antibodies in the cerebrospinal fluid of schizophrenic patients.

Antibodies to herpes simplex virus type 1 (HSV-1) were tested in the cerebrospinal fluid (CSF) of 262 schizophrenic patients by virus neutralization test (VNT) and enzyme-linked immunosorbent assay (ELISA). While VNT in the presence of complement revealed antibodies to HSV-1 in 18.3% of samples, ELISA was positive in 61.2% of cases; both tests were positive in 42 samples (16%).

Antibodies, Viral↗
PubMed1984

Association of a Sindbis-like virus with Ockelbo disease in Sweden.

An alphavirus isolated from Culiseta mosquitoes has been associated with Ockelbo disease, an exanthema arthralgia syndrome occurring in Sweden. The isolate was made from mosquitoes collected in Edsbyn (central Sweden), an area with considerable Ockelbo disease morbidity. This isolate proved to be indistinguishable from Sindbis virus by complement-fixation and hemagglutination-inhibition tests, and was antigenically related to Sindbis in plaque reduction neutralization tests. Patients with Ockelbo disease developed neutralizing antibodies to the virus in their convalescent sera, suggesting that it is the etiologic agent of the disease.

Aedes↗
PubMed1981

Immunogenicity of Staphylococcus aureus delta-toxin.

Studies were conducted to determine the immunogenicity of purified Staphylococcus aureus delta-toxin. Rabbits and guinea pigs immunized with delta-toxin incorporated into a multiple antibody, whereas animals given toxin in saline or toxin in saline with Tween 80 did not produce antibody. The immunoglobulin G (IgG) fraction isolated by chromatography on protein A-Sepharose was examined for the presence of anti-delta-toxin antibody by immunoelectrophoresis, immunodiffusion, quantitative precipitation tests, affinity chromatography, and toxin neutralization tests. Although delta-toxin-specific IgG precipitated the toxin in agar gels, the antibody did not neutralize the toxin's hemolytic activity. Delta-toxin binding to human erythrocyte membranes was demonstrated by indirect immunofluorescent staining of toxin-treated erythrocytes.

Animals↗
PubMed1965

DIFFERENCES IN CYSTINE DEPENDENCE AND CHROMATOGRAPHIC BEHAVIOR BETWEEN TWO TYPE 4 ECHOVIRUS STRAINS.

Wallis, Craig (Baylor University College of Medicine, Houston, Tex.), and Joseph L. Melnick. Differences in cystine dependence and chromatographic behavior between two type 4 echovirus strains. J. Bacteriol. 89:1310-1313. 1965.-Type 4 strains of echovirus, which are known to differ in the ease in which they can be neutralized, have been found to differ in other properties also. The prototype strain (Pesascek) differed from a readily neutralizable strain (DuToit) in that the Pesascek strain could be stabilized by cystine to thermal inactivation. Furthermore, the prototype virus required cyst(e)ine for growth under agar, whereas the DuToit strain was not affected. The viruses also reacted differently on anion-exchange resins. Pesascek virus had surface groups capable of exchanging for phosphate ions and, thus, was readily adsorbed, whereas DuToit virus was not bound by the resins under the same conditions. Only a small fraction of Pesascek virus was found to pass through the resin column. This fraction bred true, in that it yielded progeny that behaved like DuToit in not exchanging for phosphate. However, in neutralization tests, the progeny of this fraction retained the immunological property of the parent Pesascek virus.

Adsorption↗
PubMed2003

Serological evidence for Japanese encephalitis virus and West Nile virus infections in water frequenting and terrestrial wild birds in Kolar District, Karnataka State, India. A retrospective study.

In a serological survey of birds in a Japanese encephalitis (JE) endemic area of Kolar District, Karnataka State, India, 859 bird sera were tested by hemagglutination-inhibition test (HIT) for JE encephalitis and West Nile encephalitis (WNE) viruses. Only 2 (0.002%) and 178 (20.72%) sera were positive for JE virus (JEV) and WNE virus (WNV), respectively. Only 160 (18.63%) of 859 sera could be subjected to neutralizing test (NT). Of these, 20 (12.50%) and 62 (38.75%) were positive for JEV and WNV antibodies, respectively. These findings indicate that bird species such as Pond Herons and Little Egrets among ardeid birds and Grey Partridges and Quails among terrestrial birds are infected with JEV and WNV and play probably a role in the maintenance of these viruses in the abovementioned part of India.

Animals↗
PubMedDate not supplied

[Immunobiological analysis of isolated subunits of influenza virus hemagglutinin].

The immunogenic properties of isolated subunits of influenza A/FM/1/47 (H1N1) virus hemagglutinin were studied. The antihemagglutinating serum was tested by the CFT, HI, competitive solid-phase radioimmunoassay, and biological neutralization test. The antiserum was found to contain populations of antibodies to the three main antigenic determinants of hemagglutinin identical to the determinants of the intact virion, as well as antibodies to the antigenic components of host cells. The antiserum to hemagglutinin as well as monospecific antibodies to individual antigenic determinants of hemagglutinin exhibited a high virus-neutralizing activity for the homologous virus.

Animals↗
PubMed1992

A family outbreak of gastroenteritis caused by group C rotavirus.

A family outbreak of gastroenteritis caused by group C rotavirus is described. All five members of the family, with children between 8 and 15 years of age, fell ill with diarrhea. The diagnosis was initially based on the detection of rotavirus RNA showing a typical group C profile in gel electrophoresis in stool samples, and it was serologically verified from patient sera using a cell culture adapted porcine group C rotavirus as a source of standard antigen. All collected serum samples from the family contained IgM and/or IgG class antibodies to group C rotavirus measurable by immunofluorescence antibody test (IFAT). Group C rotavirus specific IgM class antibodies were present in the early serum samples in 3/4 patients. A roller tube neutralization test (NT) was established to demonstrate neutralizing antibodies to porcine group C rotavirus in human sera. These methods can be used to detect serologically group C rotavirus infections.

Adolescent↗
PubMedDate not supplied

[Tetanus prevention with vaccine and with vaccine plus heterologous immune serum: serum antibody levels in the rabbit].

Haemagglutinating antibodies have been assessed in rabbits undergoing active- passive immunization against tetanus. The animals received 6 injections of horse immune serum, 400 UI/kg, and A1PO4 adsorbed toxoid, 0.35 Lf/kg, every 30th day. One the 5th day, after the first injection, E.A. antibodies appeared, at low levels, as a result of a passive immunization. Thereafter the tests became negative, up to the 70th day, when an active immunization emerged, with a 25 days delay in comparison with controls. Neutralization test in vivo behaved in the same way. The results stress once more the need to give up the use of heterologous immune sera in tetanus prophylaxis, in active-passive immunization as well. Arguments adding force to this point of view are: the sensibilization against heterologous proteins, the very low (if any) passive protective action, and, last not least, the delay in the emergence of active immunization: the only reliable shield against tetanus.

Animals↗
PubMed1978

Serological characterization of phages of coagulase-negative staphylococci.

Selected 22 phages of coagulase-negative staphylococci were tested against group-specific antisera for Staphylococcus aureus phages using a neutralization test. Fourteen of the tested phages were classified into the serological group B and one into the group F. All other phages were resistant to the antisera against S. aureus phages but cross-reacted with the antisera produced against themselves. Therefore they could be joined together into a new serological group of the staphylococcal phages.

Bacteriophage Typing↗
PubMed1986

Neutralization of African swine fever virus by sera from African swine fever-resistant pigs.

Sera from African swine fever-resistant pigs with infection-inhibitory activity decreased virus replication in infected porcine buffy coat cultures. This same effect was observed even after virus was adsorbed. The infection-inhibition was not reversed by removing the immune serum from the assay cultures. Reduction of African swine fever virus replication by immune sera was demonstrated by fluorescent focus assay on MS cell line cultures. Virus-neutralization tests showed a persistent fraction of non-neutralized virus, which was not demonstrable by infection-inhibition tests. One hypothesis for explaining this difference is proposed.

African Swine Fever↗
PubMed1993

Seroepidemiologic survey for adenovirus infection in lambs.

A serologic survey was conducted to determine the prevalence and seroconversion rates for ovine adenovirus (OAV) serotypes 1-4 and bovine adenovirus (BAV) serotypes 2, 3, and 7 in sheep in Iowa and in surrounding states. For 2 consecutive years, paired serum samples were obtained from 1- to 2-month-old lambs as they entered a ram test station and, again, 2 months later. Sera were tested for adenovirus antibodies by use of a microtitration serum virus-neutralization test. At the time of entry, high prevalence of antibody (titer > or = 2) was detected to all tested adenoviruses except BAV-3. All adenoviruses were active in the ram test station both years, as indicated by > or = fourfold increase in adenovirus antibody titer (seroconversion) in some of the lambs. The prevalence and seroconversion rate for OAV-1 was 94.0 and 7.2%, respectively; for OAV-2, 98.6 and 15.1%; for OAV-3, 86.5 and 11.0%; for OAV-4, 98.4 and 13.2%; for BAV-2, 97.6 and 22.4%; for BAV-3, 11.4 and 3.8%; and for BAV-7, 81.6 and 4.5%. The results indicate that adenovirus infections were widespread in the sheep population and that the prevalence of active infection based on seroconversion rates was approximately 45%.

Adenoviridae Infections↗
PubMed1988

Viral hemorrhagic fever antibodies in Nigerian populations.

Using the immunofluorescence test, a serosurvey for antibodies to five viral agents associated with hemorrhagic febrile infections was conducted with 1,677 human sera from different parts of Nigeria. Three hundred fifty-seven (21.3%) were positive for Lassa virus antibody, while antibodies to Rift Valley fever virus were detected in 42 (2.5%) of the sera. Testing for Rift Valley fever virus antibody was confirmed by plaque reduction neutralization test. Antibodies to Ebola and Marburg viruses were detected in 30 and 29 sera, respectively. Of the 357 Lassa virus antibody-positive sera, 297 (83.2%) were positive for Lassa only. In contrast, sera positive for Marburg were positive in combination with Lassa, Ebola, or Rift Valley fever viruses. Antibodies to Lassa and Rift Valley fever viruses were found in all locations in Nigeria, whereas Ebola and Marburg antibodies were found mainly in the northern savanna zones of Benue and Gongola, but not in the rain forest area of Ondo.

Adolescent↗
PubMed1989

Immunity to diphtheria in a sample of adult population from central Italy.

A sample of 643 healthy subjects from central Italy aged 20 to 80, were screened for diphtheria antitoxin. Serum diphtheria antitoxin was assayed by a new passive haemagglutination technique using turkey red blood cells sensitized with diphtheria toxoid, after having performed a correlation study between this technique and the reference in vivo neutralization test. Of the studied population 26.7% showed a lack of serum antitoxin titres considered to be protective. The rate of susceptible subjects increased with age, showing the highest value (38.9%) in the sixth decade of age. Males proved less protected than females; 53.2% of the male population aged 50-59 were lacking a protective anti-diphtheria immunity. On the basis of present results, a periodical revaccination of the entire adult population with reduced doses of diphtheria toxoid would be advisable.

Adult↗
PubMed1992

Reovirus type 2 in domestic cats: isolation and experimental transmission.

Five reovirus isolates were recovered in MA104 cell cultures from the faeces of three cats with nictitating membrane protrusion and diarrhoea, one cat with diarrhoea only and from one healthy cat. Four of these isolates were characterised as reovirus type 2 and one as reovirus type 3 by haemagglutination-inhibition and serum neutralization tests. Reovirus type 2 has not been reported previously in cats. Mild clinical signs of diarrhoea were noted in kittens infected experimentally with one of the feline reovirus type 2 isolates.

Animals↗
PubMed2003

Biological and immunochemical characterization of Micrurus altirostris venom and serum neutralization of its toxic activities.

Micrurus altirostris venom from Rio Grande do Sul State, Brazil, was characterized by its biological activities, immunochemical properties and electrophoretic pattern. The results showed a high edematogenic activity, whose peak was observed after 30min of venom injection, as well as a high indirect hemolytic activity. This venom was myotoxic, as shown by a peak of CK release at 6h after injection, and also by the appearance of muscular lesions characterized by necrosis, loss of striated muscle fibers, and the presence of vacuolization, edema and inflammatory infiltrate. This venom showed minimum proteolytic activity and no hemorrhagic, dermonecrotic or coagulant activities. Nonetheless, M. altirostris venom presented high lethal activity. Electrophoretic patterns of Micrurus frontalis and M. altirostris venoms showed different protein bands. Anti-elapidic serum could recognize M. frontalis (homologous) and M. altirostris (heterologous) venoms by Western blotting, and both venoms presented similar titers when assayed by ELISA. The results observed on neutralization tests showed that the anti-elapidic serum produced by Instituto Butantan neutralized myotoxic and hemolytic activities. However, this antivenom could not neutralize the lethal activity of M. altirostris venom. Thus, these data suggest that M. altirostris venom presents different biological, enzymatic and immunological characteristics from other Micrurus venoms, and some activities are not neutralized by the commercial anti-elapidic serum produced in Brazil.

Animals↗