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C Kunz

Publications and source records attributed to C Kunz.

At least 217 records · Page 12Linked to original sources
PubMed1983

A topological and functional model of epitopes on the structural glycoprotein of tick-borne encephalitis virus defined by monoclonal antibodies.

A topological and functional model of eight distinct epitopes on the structural glycoprotein of tick-borne encephalitis (TBE) virus was established by the use of monoclonal antibodies. The unique specificities and spatial relationships of these antibodies were determined by variant analysis, haemagglutination inhibition (HI), neutralization, passive mouse protection, and antibody blocking assays. Seven out of the eight distinct epitopes were shown to be partially linked and to cluster in two antigenically reactive domains (A, B). Each of these domains is inhomogeneous and contains constituents with different serological specificities and functions. Domain A is defined by three HA-inhibiting antibodies, two of which are flavivirus group-reactive, whereas the third is TBE virus subtype specific. Within this domain only the subtype-specific antibody is involved in virus neutralization, thus explaining the observation that neutralization tests with flaviviruses show higher serological specificities than HI tests and that HI tests can be made type and subtype specific by antibody absorption. Domain B is composed of three TBE-complex reactive epitopes, and the corresponding antibodies inhibit HA and neutralize the virus. A fourth epitope linked to this domain is neither involved in HA nor in neutralization and the same holds true for a subtype-specific epitope which is topologically independent of domains A and B. Each of two different nonneutralizing antibodies was capable of blocking the binding of distinct neutralizing antibodies. All eight epitopes are indistinguishably present on strains of the western subtype of TBE virus isolated all over Europe in different years from different hosts, thus again confirming the great stability of this virus.

Animals↗
PubMed1983

Amino acid compositions and amino-terminal sequences of the structural proteins of a flavivirus, European Tick-Borne Encephalitis virus.

N-terminal amino acid sequences of the three structural proteins E, C, and M of the flavivirus Tick-Borne Encephalitis virus comprising 4, 17, and 4 amino acid residues, respectively, have been determined. Each of these proteins has a unique N-terminal sequence. Since none of the three proteins possesses an N-terminal methionine residue, none contains an unprocessed translation initiation sequence. The amino acid composition of the three proteins has also been analyzed. The C protein is rich in basic amino acids. It contains neither tyrosine nor cysteine. The M protein is rich in leucine and contains only single residues of methionine and phenylalanine. The amino acid composition indicates that the M protein has a molecular weight of at least 8000 Da which is somewhat higher than the value of 7500 Da estimated for the molecular weight of this protein by SDS-PAGE. Further conclusions that can be drawn from these analyses are discussed.

Amino Acid Sequence↗
PubMed1982

Studies in man with a cold-recombinant live influenza B virus vaccine.

A cold recombinant live influenza B virus vaccine was tested in man. In comparison to a placebo, reactogenicity attributable to virus infection was slight or moderate. No revertant viruses were shed, and there was no evidence of transmission to the placebo group who were housed in close contact with the vaccinees. Serological responses to initial inoculation were moderate; 60% of vaccinees showing twofold increases in serum hemagglutination inhibition (HAI) titers gave a geometric mean titer (GMT) of 1:13. Three weeks after the first vaccination, both the vaccine and the placebo group were revaccinated with homologous live virus vaccine. The group previously given vaccine was resistant to reinfection as judged from clinical reactions and virus shedding and the GMT increased only slightly to 1:16.3. In contrast, the former placebo group responded; mild symptoms were seen, the majority shed viruses and 50% showed twofold increases in serum HAI titers to a geometric mean titer of 1:17.4.

Adult↗
PubMed1982

Antibody response after application of a new live attenuated mumps vaccine (Pariorix) measured by enzyme-linked immunosorbent assay (ELISA).

Mumps virus specific antibody concentrations were determined by enzyme-linked immunosorbent assay (ELISA), hemolysis-in-gel (HIG) test, and hemagglutination-inhibition (HI) test in 17 adult volunteers before and after vaccination with a new live mumps vaccine, Pariorix. The results of the present study indicate that the strain Urabe-Am 9 of the mumps virus (Pariorix) induces antibodies in 100% of seronegative adults when measured by ELISA and in 70.6% and 64.7% in HIG and HI, respectively. ELISA is therefore a very sensitive and reliable method for the demonstration of sero-conversion after vaccination. The vaccine was well tolerated and clinically acceptable in the group of adult volunteers.

Adult↗
PubMed1982

Molecular epidemiology of tick-borne encephalitis virus: peptide mapping of large non-structural proteins of European isolates and comparison with other flaviviruses.

Nine virus-specified proteins were identified by SDS-polyacrylamide gel electrophoresis in [35S]methionine-labelled chick embryo cells infected with tick-borne encephalitis (TBE) virus by comparison with mock-infected cells. These proteins were designated P91, p74, p72, P67, GP53(E), P47, p25, P15(C) and P14.5 according to their molecular weights. Peptide mapping of P91, P67, GP53(E) and P47 from TBE virus-infected cells, as well as those of the corresponding proteins from West Nile virus (WNV)-infected cells (previously termed NV5, NV4, V3 and NV3), demonstrated the uniqueness of these proteins. Almost no subtype variability, with respect to the pattern of intracellular proteins, was found when isolates of TBE virus from Austria, Switzerland, Germany, Finland and Czechoslovakia were compared. Peptide mapping of NV5 (P91) and NV4 (P67) from all these isolates using limited proteolysis with alpha-chymotrypsin and V8 protease revealed completely identical patterns, thus extending our observations that TBE virus seems to represent a very stable member of the flavivirus genus, which was based on the lack of variation found with the structural glycoprotein. On the other hand, the Far Eastern subtype of TBE virus and the closely related louping-ill virus could not only be differentiated from the Western subtype by differences in the peptide maps of their structural glycoprotein but also in those of the non-structural protein NV5, i.e. subtype or subgroup variations are not confined to the virion surface glycoprotein. WNV and Murray Valley encephalitis virus (MVEV) revealed the expected heterogeneity of virus-specified proteins found in cells infected with different flaviviruses. It is especially interesting that also the largest non-structural protein, NV5, is subject to this heterogeneity, ranging in mol. wt. from 91 000 for TBE virus to 98 000 for MVEV and that also the peptide maps of NV5, as well as those of NV4, were unrelated. These proteins, therefore, revealed a variability between serologically distinct flaviviruses similar to that observed with the structural glycoprotein.

Encephalitis Viruses, Tick-Borne↗
PubMed1982

Monoclonal antibodies to the structural glycoprotein of tick-borne encephalitis virus.

Hybridomas secreting antibodies to the structural glycoprotein of tick-borne encephalitis (TBE) virus were prepared by fusion of X63-Ag8/653 mouse myeloma cells with spleen cells from mice immunized with purified glycoprotein complexes of TBE virus. These antibodies were tested against 10 different TBE virus strains isolated in different European countries over a period of 26 years from different hosts. Quantitative evaluation of enzyme immunoassay results did not reveal any differences in reactivity among these strains, pointing further to the homogeneity of European TBE virus isolates, which has previously been inferred from results obtained by peptide mapping and competitive radioimmunoassay. Hybridomas defining three different antibody-combining sites (epitopes) on the glycoprotein of TBE virus were selected on the basis of cross-reactivity with another flavivirus. West Nile virus, as well as the ability to inhibit hemagglutination. Two epitopes were type specific, and the third was indistinguishably also present on West Nile virus. Hemagglutination was inhibited by monoclonal antibodies reacting with one of the type-specific epitopes as well as the cross-reactive determinant, which is apparently responsible for the broad cross-reactivity among different flaviviruses observed in hemagglutination inhibition tests with polyvalent immune sera.

Animals↗
PubMed1982

[25-hydroxy-vitamin-D in serum of newborns and infants during continuous oral vitamin D treatment (author's transl)].

Using the Haddad modified method, 25-OH-D were measured in the blood of the umbilical cord of 29 infants and in peripheral serum after 6 weeks. 16 infants were given a daily dosage of 1000 I. E., 13 infants 500 I. E. vitamin D against rickets. Further they were fed with an adapted milk containing 400 I. E. vitamin D/1. The mean cord serum values were 13 and 15 ng/ml. After treatment with 1000 I. E., 25-OH-D values around 54 ng/ml were measured after 6 weeks and under 500 I. E. daily, values of 37 ng/ml, respectively. Treatment using a dosage of 500 I. E. vitamin D combined with feeding with vitamin D fortified milk seems adequate, to prevent vitamin D depletion.

25-Hydroxyvitamin D 2↗
PubMed1981

[Laboratory diagnosis of viral diseases of the skin (author's transl)].

In order to establish the diagnosis of viral diseases with clinical manifestations in the skin, frequently the help of a virus laboratory is needed. Not even classical childhood diseases such as measles and rubella can safely be diagnosed by the clinician. Today, in many cases diagnosis is possible within hours after the arrival of clinical specimens in the laboratory. Only in cases of enterovirus infection and tropical diseases has the virologist to resort to the classical time-consuming methods of direct (virus isolation) or indirect (serologic) diagnostic virology.

Antibodies, Viral↗
PubMed1981

[Efficacy of specific immunoglobulin against TBE (author's transl)].

The efficacy of passive immunization against tickborne encephalitis (TBE) was evaluated in Vienna by means of a telephonic survey. It was learned that in 1979 after a tickbite in endemic areas, of TBE, approximately one out of 1,000 unvaccinated persons came down with the disease. Administration of TBE immunoglobulin after exposure reduced the incidence of the disease to 1:2,500. thus showing a rate of protection of approximately 60%. The survey also showed that in 1979 one third of those at risk (frequent walks in forests) had already undergone active immunization with the Austrian TBE vaccine.

Austria↗
PubMed1981

[Gamma globulin as a prophylactic measure in an outbreak of hepatitis A in an institution for mentally retarded children (author's transl)].

An outbreak of hepatitis A was observed in an institution for mentally handicapped children. Within 2 months 21 cases occurred in 4 out of 7 groups. By means of gamma-globulin administration and measures of general hygiene, the outbreak, although not immediately stopped, was brought under control. The number of overt cases was reduced and further transmission to 3 other groups was prevented. The detection of IgM antibodies to hepatitis A virus proved to be very suitable for diagnostic purposes. Subsequently it turned out that the gamma-globulin used had a very low titre in comparison with other preparations. Recommendations are given to prevent similar outbreaks in the future.

Antibody Formation↗
PubMed1981

[Detection of rotavirus in infants with acute gastroenteritis (author's transl)].

Throughout 1978, stools of Austrian infants and young children with gastroenteritis were investigated for the presence of viruses by means of electron microscopy. Rotavirus was found in 131 out of 590 children. Adenoviruses were observed in 18 cases. The viruses were detected more often during the cold season, particularly in children up to two years of age.

Acute Disease↗
PubMed1981

Serological diagnosis of acute tick-borne encephalitis by demonstration of antibodies of the IgM class.

A sensitive enzyme immunoassay is described for demonstrating specific antibodies of the IgM class to tick-borne encephalitis virus (anti-TBEV IgM). Anti-mu-coated, flat-bottomed microtiter plates are incubated with diluted patients' serum (2 hr at 37 degrees C), then with purified TBEV, and later with peroxidase-coupled anti-TBEV immunoglobulin for a further 2 hr. After washing the plates, orthophenylenediamine is added and the optical density is measured at 510 nm. At an early stage after onset of illness anti-TBEV IgM could be demonstrated up to serum dilutions of 10(-4). The specificity of the test system was shown by total inhibition of the positive reaction by preincubation of patients' sera with anti-mu. Tick-borne encephalitis (TBE) could be diagnosed serologically in 54 patients by the described method, and anti-TBEV IgM could be demonstrated in sera drawn up to 9 months after onset of illness. A peak in the number of infections occurs in the age group of 31-40 years, and most infections occur from June to October with a small peak in July.

Adolescent↗
PubMed1981

Homogeneity of the structural glycoprotein from European isolates of tick-borne encephalitis virus: comparison with other flaviviruses.

Isolates of tick-borne encephalitis (TBE) virus from Finland, Germany, Czechoslovakia, Switzerland and Austria were compared with strains of the Far Eastern subtype isolated in Russia as well as Louping ill virus and other flaviviruses belonging to a different serocomplex: West Nile, Murray Valley encephalitis and Rocio viruses. Analysis of the structural polypeptides by SDS--polyacrylamide gel electrophoresis (SDS--PAGE) revealed identical mol. wt. of the glycoprotein E (mol. wt. 55 000) and the core protein C (mol. wt. 15 000) for all the TBE virus strains analysed. However, the small envelope protein M from viruses isolated in Germany, Switzerland and Austria migrated slightly slower (apparent mol. wt. 7500) compared to M from viruses isolated in Finland, Czechoslovakia or the Far Eastern subtype strains (apparent mol. wt. 6500 to 7000). The structural glycoproteins were isolated from purified [35S]methionine-labeled virions and subjected to peptide mapping by limited proteolysis with alpha-chymotrypsin or V8 protease followed by SDS--PAGE of the resulting cleavage products. With both proteases a remarkably homogeneous pattern was obtained for all the European isolates with only very minor deviations from a common pattern in single cases. Similar but distinguishable patterns were obtained for the Far Eastern subtype strains and also Louping ill virus, which, in addition, differed in the mol. wt. of its core protein C (mol. wt. 16 000) and the small membrane protein M (mol. wt. 9000). These almost identical peptide maps observed with the TBE virus strains were in sharp contrast to the unrelated patterns obtained with the glycoproteins from West Nile, Murray Valley encephalitis and Rocio viruses. Although these viruses are serologically closely related and members of the same serocomplex of flaviviruses their glycoprotein peptide maps were completely different from one another. In a competitive radioimmunoassay all European TBE virus isolates showed identical immunological reactivity which further points to the great stability of this type of virus.

Encephalitis Viruses, Tick-Borne↗
PubMed1981

Antigenic and immunogenic properties of defined physical forms of tick-borne encephalitis virus structural proteins.

Polymeric, delipidated glycoprotein complexes of defined size and composition were prepared from tick-borne encephalitis virus by solubilization with Triton X-100 or cetyltrimethylammonium bromide, followed by centrifugation into detergent-free sucrose density gradients. The antigenic reactivities and immunogenicities of these complexes were compared with those of complete inactivated virus. These glycoprotein preparations induced hemagglutination-inhibiting and neutralizing antibodies which proved to be protective in passive mouse protection tests and monospecifically reacted only with the viral envelope and not with the internal core. In a competitive radioimmunoassay the glycoprotein complexes revealed about 10-fold higher antigenicity than whole virus when tested at equal protein concentrations. The important implications of these results with respect to antigen quantification in vaccines are discussed. As shown in the mouse challenge potency test, glycoprotein complexes prepared after Triton X-100 solubilization actively protected mice almost as well as did complete inactivated virus at the same protein concentration, whereas those prepared after cetyltrimethylammonium bromide solubilization had a somewhat lower protective activity per microgram of protein.

Animals↗
PubMed1981

Comparison of two different enzyme immunoassays for detection of immunoglobulin M antibodies against tick-borne encephalitis virus in serum and cerebrospinal fluid.

Two enzyme immunoassays for the detection in immunoglobulin M (IgM) antibodies against tick-borne encephalitis virus were compared, employing a solid phase coated either with antigen or with mu-chain-specific antiserum to human IgM. The latter IgM-capturing assay system proved to be more sensitive, and its superiority was especially prominent when high titers of tick-borne encephalitis virus-specific IgG antibodies in addition to specific IgM antibodies were present in the sample. The application of this test is a valuable extension of the diagnostic tools for the rapid diagnosis of tick-borne encephalitis by IgM detection. Since specific IgG does not interfere, diagnosis can be readily established when patients have already developed high titers of IgG antibodies relatively late after the onset of the disease.

Antibodies, Viral↗