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At least 1,657 records · Page 92Linked to original sources
PubMed1987

Rotavirus isolate WI61 representing a presumptive new human serotype.

A virus (strain WI61) representing a presumptive new human serotype was isolated from an 18-month-old child with gastroenteritis admitted to Children's Hospital of Philadelphia in February 1983. The WI61 virus was clearly distinguished by cross-neutralization tests from human rotaviruses of serotypes 1, 2, 3, and 4, human 69M, and representative bovine (NCDV), porcine (OSU), and chicken (Ch2) rotaviruses. Antisera generated in guinea pigs hyperimmunized to WI61 virus displayed a partial cross-reactivity with rotaviruses of human serotypes 1, 2, 3, and 4. By means of studies with reassortant rotaviruses, it was presumptively determined that the WI61 virus cross-reactive antigenic determinants are localized on the vp3 surface polypeptide coded by gene segment 4. The characteristic RNA genome electropherotype of WI61 virus was observed in 5 of 59 cases of infant gastroenteritis detected in 1983 and 1984 but has not been observed in a subsequently at Children's Hospital. Serotype WI61-specific neutralizing antibodies were observed in a majority of sera of normal adults and infants of less than 4 or greater than 12 months of age collected in the Philadelphia area. Median antibody titers to WI61 equaled or exceeded those to rotaviruses of serotype 1 or 3. Each of seven samples of commercial cow's milk exhibited neutralizing antibodies to WI61 virus at a titer greater than or equal to that to serotype 1 or 3 or bovine (strain NCDV) rotavirus. However, WI61 rotavirus did not induce disease or a specific serum-neutralizing antibody response when fed to a caesarean-derived colostrum-deprived newborn calf. WI61 rotavirus caused diarrhea in newborn mice with a 50% diarrhea-inducing dose of 10(7.0) PFU.

Animals↗
PubMed1985

Anti-tumour effect of humoral and cellular immunities mediated by a bacterial immunopotentiator, Lactobacillus casei, in mice.

Administration of a mixture containing Lactobacillus casei YIT 9018 (LC9018) and methylcholanthrene-induced fibrosarcoma (Meth A) cells into the peritoneum of syngeneic BALB/c mice suppressed the tumour growth and protected the mice from tumour death. With the appearance of the anti-tumour activity, serum complement-dependent tumour cytotoxic (CDC) antibody was induced on the 5th day after the administration as a result of the adjuvant effect. The cytotoxic antibody was not found in serum on the 5th day after inoculation of Meth A cells alone, but it was induced before the mice died of the tumours. Adjuvant induction of the cytotoxic serum antibody at an early time was also observed using Kirsten murine sarcoma virus-transformed tumour (K234) cells. Both of these cytotoxic antibodies in sera from Meth A-suppressed and the tumour-bearing mice were specific for the tumour cells and were IgM class, since they were absorbed with rabbit anti-mouse IgM antibody. However, the cytotoxic antibody was not found in the peritoneal cavity which was the tumour inoculation site, but binding antibody against the tumour cells was faintly detected in the region using an enzyme-linked immunoabsorbent assay (ELISA). In neutralization tests, the cytotoxic antibody did not exert anti-tumour activity in recipient mice when it was administered to the mice along with the tumour cells or when it was administered i.v. at the time of tumour inoculation. Moreover, the cytotoxic antibody was not available for the antibody-dependent cell-mediated cytotoxicity (ADCC). These results suggest that the cytotoxic antibody did not exert anti-tumour activity in the tumour-suppressed mice. In contrast, peritoneal exudate cells (PEC) on the 5th day, and PEC and spleen cells on the 15th day after i.p. administration of the mixture exerted strong anti-tumour activity as measured by the Winn test. In conclusion, the adjuvant effect of LC9018 induced tumour-specific humoral and cellular immunities but the anti-tumour activity was dependent only on the cellular effectors of the host. The possible use of LC9018 in tumour immunotherapy is discussed.

Adjuvants, Immunologic↗
PubMed1989

Isolation and preliminary characterization of an orbivirus of the Palyam serogroup from biting midge Culicoides oxystoma in Japan.

An orbivirus of the Palyam serogroup was isolated from Culicoides oxystoma collected in a cowshed in Kagoshima, Southern Kyushu Island, Japan. This is the first isolation of an orbivirus of the Palyam serogroup in Japan. The virus was a spherical non-enveloped RNA virus, approximately 60 nm in diameter. The virus was resistant to ethyl ether, sodium deoxycholate and freezing-thawing, but readily inactivated by trypsin. The virus was not stabilized by 1 M MgCl2, was labile at pH 3.0 and was not precipitated by protamine sulfate. Indirect immunofluorescent staining of infected Vero cells indicated the virus to be antigenically related to D'Aguilar and Bunyip Creek viruses of the Palyam serogroup. Neutralization tests showed the virus to have no relationship with D'Aguilar virus, but to have a one-way cross-reaction with Bunyip Creek virus. The virus was tentatively designated as Kagoshima virus. A serological survey indicated dissemination of the virus in cattle populations in Kagoshima Prefecture.

Animals↗
PubMed1987

Bovine milk immunoglobulins for passive immunity to infantile rotavirus gastroenteritis.

Pregnant cows were successfully hyperimmunized with all four human rotavirus serotypes, resulting in a 100-fold increase in neutralizing milk antibody titers over those of controls. Milk antibodies were isolated batchwise from 1,000 kg of pooled milk for the first 10 lactation days, yielding 10 kg of freeze-dried milk immunoglobulin concentrate consisting of 50% bovine milk immunoglobulins. Milk immunoglobulin concentrate showed neutralizing activities against all four human rotavirus serotypes that were 100 times higher than those in pooled human milk samples and 10 times higher than those in a commercial pooled immunoglobulin preparation from pooled human blood serum. In vitro neutralization tests showed that milk immunoglobulin concentrate had powerful antiviral activity, even against very high doses of infectious rotaviruses. Because the technology of the milk immunoglobulin concentrate ensures that it is innocuous and can be used for oral application, it is proposed that milk immunoglobulin concentrate be used to induce passive immunity to infantile rotavirus gastroenteritis.

Animals↗
PubMedDate not supplied

[Intratypical antigenic differentiation of poliovirus strains circulating in Mali by means of cross-adsorbed sera].

The intratypic antigenic differentiation of poliovirus strains isolated from sick or healthy children in Mali in 1975-1976 was performed. The method is based on the use of cross-adsorbed sera in the neutralization tests in which the virus is titrated by the plaque procedure or by the cytopathic effect. All the examined strains of serologic types I, II, and III were distinguished by the antigenic structure from the vaccine strains and were classified as "wild". Quantitative differences in the antigenic structure of type I strains isolated in different towns of Mali were found.

Adsorption↗
PubMed1987

The effects of reductions in the numbers of animals used for the potency assay of the diphtheria and tetanus components of adsorbed vaccines by the methods of the European pharmacopoeia.

Forty eight assays of adsorbed diphtheria vaccine and seven assays of adsorbed tetanus vaccine using either a lethal challenge (38 assays) or a serum neutralization test (17 assays) were evaluated for the effects of reductions in the number of animals used at each dilution on the potency values and 95% confidence intervals. The results were assessed in the light of the requirements of the European Pharmacopoeia and the WHO. In the majority of assays, 50% of the number of animals presently required would have sufficed for the determination of a potency within the limits of confidence stipulated by the European Pharmacopoeia and the WHO. Therefore it is concluded that a simplified assay with a reduced number of animals is suitable for the routine potency testing of the diphtheria and tetanus components of the combined vaccines and the monovalent that were examined. Flexibility in the national and international requirements in respect of the numbers of animals used at each dilution is suggested for the routine potency assay of the diphtheria and tetanus components of adsorbed vaccines.

Animal Welfare↗
PubMed2001

Duration of bluetongue viremia in experimentally infected American bison.

Six yearling American bison (Bison bison bison) bulls and one yearling ewe (Ovis aries) were inoculated intradermally and subcutaneously with 2 x 10(5) plaque forming units (pfu) of bluetongue (BT) virus serotype 11. Two uninoculated yearling bison bulls served as negative controls. Blood samples were collected for serology and virus isolation on 0, 4, 7, 11 and 14 days post-inoculation (dpi) and every 2 wk thereafter to 127 dpi. Every 4 wk a new ewe was inoculated with a pooled sample of whole blood from the six infected bison, and each sheep was monitored for 28 days for clinical signs of BT and seroconversion. Bluetongue viremia was detected in all six inoculated bison starting at 4 to 28 dpi and was no longer detectable from 42 dpi onward. Pooled blood samples collected at 28, 56, 84 and 112 dpi from the six infected bison were not infectious for sheep. The six infected bison seroconverted by 11 to 28 dpi on a competitive enzyme-linked immunosorbent assay and by 28 dpi on the serum neutralization test, and all remained seropositive thereafter. No clinical signs or lesions attributable to BT were observed in the infected bison or controls. There was evidence that a small amount of epizootic hemorrhagic disease virus type 2 had been present in the BT virus inoculum; reasons are given for concluding that this did not affect the results of the BT study.

Animals↗
PubMedDate not supplied

[Biological properties of the chick infectious bronchitis virus isolated in Russia].

A field chick infectious bronchitis virus (IBV) was isolated from the pathological material on chick embryos. The nucleotide sequence of the S1 gene was determined and comparatively analyzed with some sequences of this gene of foreign and Russian vaccine strains and isolates. A cross-neutralization test using sera to various IBV seroptypes was performed. The isolate was shown to antigenically differ from the reference strains. Bioassay was carried out, by using one-day chicks and the immunogenic properties of the virus were investigated.

Animals↗
PubMed1981

Serologic and molecular comparisons of several equine herpesvirus type 1 strains.

The molecular and serologic relatedness of 2 recent respiratory tract isolates of equine herpesvirus type 1, designated T1 and T2, were compared with the Army 183, Kentucky-A hamster-adapted (KyA-ha), and L-M cell-adapted (KyA-LM) strains. Electrophoresis in polyacrylamide gels revealed differences in virion structural proteins among 4 purified strains. Seven envelope glycoproteins (molecular weight of 93,000, 65,000, 62,000, 60,000, 36,000, 20,000, and 18,000) corresponding to virion proteins 13, 16, 17, 18, 23, 25, and 26a, respectively, found in both the Army 183 and KyA-ha strains had slightly different molecular weight counterparts in both the T1 and T2 isolates, which had identical structural protein profiles. virion protein 19 (58,000 daltons), a nonglycosylated protein, was present in reduced amounts in the respiratory tract isolates, whereas virion protein 8a (200,000 daltons) was absent. Virion protein 8a, an envelope glycoprotein, was only present in the KyA-ha strain. The T1 and T2 isolates were not neutralized by equine herpesvirus type 2 antiserum and revealed little cross-neutralizatio with the Army 183 and KyA-ha strains in plaque-reduction neutralization tests. Restriction endonuclease cleavage maps of viral DNA revealed a similar, but not identical, number and size of DNA fragments between T1 and T2 isolates. Likewise, DNa profiles of Army 183, KyA-ha, and KyA-LM were also similar to each other, but vastly different from the respiratory tract isolates.

Animals↗
PubMed1985

Numerical comparative serology of the Bhanja antigenic group (Bunyaviridae).

Antigenic relationships between the two known members of the Bhanja serogroup (Bhanja virus, 7 strains; Kismayo virus, two strains) were studied by a plaque-reduction cross-neutralization test in Vero cells, using hyperimmune mouse sera. The results were then subjected to a cluster analysis, which showed (in the form of a dendrogram) a considerable antigenic difference between the two viruses. Within Bhanja virus, the European isolates from Haemaphysalis punctata or H. sulcata ticks were antigenically indistinguishable, while the strains isolated in Africa and Asia from other tick species differed slightly from the European strains and also from each other.

Africa↗
PubMed2000

An epizootic of adenovirus-induced hemorrhagic disease in captive black-tailed deer (Odocoileus hemionus).

Ten fawns and four adult black-tailed deer (Odocoileus hemionus) in a captive herd died as a result of adenovirus-induced hemorrhagic disease. Acute, systemic infections were characterized by hemorrhagic enteropathy, pulmonary edema, and occasional ulceration of the upper alimentary tract. Localized infections were limited to the upper alimentary tract and included stomatitis, pharyngitis, mandibular osteomyelitis, and rumenitis. In deer with acute, systemic infections, a diagnosis was made by histopathology and immunohistochemistry. The serum neutralization test was useful for confirming a diagnosis in animals with prolonged, localized infections. Deer originating from herds with a history of adenovirus infection should not be transferred to other captive herds or released into free-ranging populations because they may serve as carriers of adenovirus.

Adenoviridae↗
PubMed1987

Preliminary characterization of an inhibitory activity of fetal bovine serum on the infectivity of rotavirus strain SA-11.

In the present work we studied non antibody inhibiting activity present in fetal bovine serum and active to Rotavirus infectivity and growth in cell cultures. This inhibitor was revealed by an in vitro neutralization test and characterized by gel filtration and chemical and enzymatic treatments. Furthermore, commercial preparations of bovine serum proteins were tested for inhibitory activity. Our results show that serum inhibition is partially resistant to trypsin and neuraminidase treatments but completely destroyed by KIO4. A similar activity was observed in a commercial serum bovine fraction containing predominantly alpha-globulins. These results seem to indicate that glycoproteins, and their glucidic components are the molecules predominantly involved in serum inhibition towards Rotavirus infectivity.

Animals↗
PubMed1979

Antigenic specificity of neutralizing antibody to cholera toxin.

Selected rabbit antisera to cholera toxin antigens and convalescent cholera patient sera were analyzed using the permeability factor neutralization test and two sensitive in vitro serological assays specific for cholera toxin, cholera toxin A subunit, and cholera toxin B subunit. The results indicated that antisera to cholera toxin contained toxin-neutralizing activity as well as antibodies specific for both the A subunit and B subunit. It was clearly established that antisera to B subunit, devoid of significant anti-A subunit activity, neutralized the vascular permeability activity of cholera toxin. Antisera to A subunit contained neutralizing antibodies and antibodies to both A and B subunits. Absorption with B subunit removed both the toxin-neutralizing and anti-B subunit activities, while the anti-A activity was unaffected. Neutralizing antibody titers of rabbits immunized with B subunit were also observed to be significantly higher than neutralizing antibody titers of sera from A subunit-immunized rabbits, despite the overall similarity in anti-B subunit titers as determined by passive hemagglutination and radioimmunoassay of sera from the two groups of rabbits. Anti-alpha chain sera neither neutralized cholera toxin nor possessed significant antitoxin or anti-B subunit titers as determined by passive hemagglutination and radioimmunoassay. The anti-alpha chain sera contained high levels of antibody specific for A subunit, which is consistent with the hypothesis that the alpha chain is part of the A subunit structure. In contrast, the gamma chain was not shown to be antigenic. Sera from convalescent cholera patients possessed toxin-neutralizing antibody as well as passive hemagglutination and radioimmunoassay antibody against both A and B subunits.

Animals↗
PubMed1975

Arbovirus infection of vertebrate and insect cell cultures, with special emphasis on Mokola, Obodhiang, and kotonkan viruses of the rabies serogroup.

Multiplication of rabies serogroup viruses, Obodhiang and kotonkan (two presumptive arboviruses), was induced in vertebrate cell cultures with Singh's A. albopictus cell cultures used as "helper cells" in cocultivation experiments. Plaque formation without prior in vitro adaptation was induced in Vero cell cultures with eight rabies serogroup viruses: in all five instances by cocultivation of either infected BHK-21 or A. albopictus cells with Vero cells under agar overlay and in three of eight instances by direct plaque assay of infected mouse brain suspensions. In cross-plaque reduction neutralization tests with cloned viruses that represented human pathogens, rabies, Duvenhage, and Mokola, on the one hand, and the presumptive arboviruses Obodhiang and kotonkan, on the other hand, Mokola virus shared common antigenic components with both the nonarboviruses and the arboviruses. Biologically, Mokola virus was different from the other two human pathogens, rabies and Duvenhage, in that it multiplied in both vertebrate and invertebrate cell cultures. Mokola virus thus appears to be the biologic and serologic bridging agent.

Aedes↗
PubMed1977

[A simple micro-procedure in virological and serological diagnosis].

The author reports on a micro-neutralization test which makes it possible to detect the antibodies against 7 different respiratory viruses (adeno and parainfluenza viruses) using only 0.080 ml of serum from patient. Swaged PVC foil used for packing pharmaceuticals, also known here as strip packing or press-through packing for pills and dragees was employed as plates for the cultures. This material is not toxic for the cell cultures, it is cheap and suitable also for other microbiological work in the field of serology.

Adenoviridae↗
PubMed1987

An ELISA for the detection of rhinovirus specific antibody in serum and nasal secretion.

An enzyme-linked immunosorbent assay (ELISA) which detects rhinovirus specific antibody in human sera and nasal secretions, has been developed. This sandwich ELISA utilizes a rabbit antirhinovirus hyperimmune serum as the capture antibody and was found to be very sensitive, detecting rhinovirus specific antibody in the serum at dilutions of 1:10(6) and 1:10(3.5) for IgG and IgA immunoglobulins, respectively. Thus, this new assay is 10(2)-10(4) times more sensitive than our standard neutralization test. Furthermore, this increase in sensitivity has enabled us to reliably detect rhinovirus specific immunoglobulins in unconcentrated nasal washings, which are thought to be particularly important for protection against rhinovirus reinfection. A preliminary study of the immune response in human volunteers challenged with rhinovirus using this new ELISA system is presented and further applications and potential of the method are also discussed.

Antibodies, Viral↗
PubMed1995

Evidence for the existence of Puumula-related virus among Clethrionomys rufocanus in Hokkaido, Japan.

We conducted field surveys of indigenous rodent species in Hokkaido, Japan from 1980 to 1993. Serum samples were collected from 663 rodents, including Clethrionomys rufocanus, Apodemus speciosus, A. argenteus, and C. rutilus. Antibody to hantavirus was determined by the protein G antibody assay. Positive C. rufocanus were detected in seven of eight collection sites, but no antibody was detected in the remaining rodent species. To reveal the serotype of the circulating virus in C. rufocanus, antibody titers to Hantaan, Seoul, Puumala, and Prospect Hill viruses were compared by means of the focus reduction neutralization test. The titers in positive sera were extremely high to the Sotkamo strain of Puumala virus. Results were confirmed by the reverse transcriptase-polymerase chain reaction, and suggested that Puumala-related viruses are in circulation among C. rufocanus populations in Hokkaido.

Animals↗
PubMed1973

Role of coxsackievirus B4 in the pathogenesis of acute glomerulonephritis.

Coxsackievirus B(4) was isolated from the throat, nose, blood, stools and urine of a 9-year-old boy with acute glomerulonephritis and a pneumonitis. Neutralization test showed a greater than fourfold rise in the antibody titre to coxsackievirus B(4). The antistreptolysin O titre was elevated, but the complement component was within the normal range. The importance of the coxsackievirus B(4) in the pathogenesis of acute glomerulonephritis is clearly indicated; however, further investigations are needed to understand the details of the virus-kidney interaction.

Acute Disease↗