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L Grubhoffer

Publications and source records attributed to L Grubhoffer.

At least 37 records · Page 2Linked to original sources
PubMed1994

Some properties of sialic-acid binding systems in Tritrichomonas suis and Tritrichomonas foetus.

Hemagglutination of normal and enzyme-treated red blood cells and its inhibition, in vitro adherence to porcine caecal mucus and kinetic properties of neuraminidase were carried out with Tritrichomonas suis and T. foetus. All tested strains adhered extensively to porcine caecal mucus in vitro and agglutinated human (A1, A2, B and O), rabbit, porcine and hen red blood cells. Different inhibitors were efficacious in hemagglutination activity (HA) tests using neuraminidase treated and untreated red blood cells. The Scatchard plot showed an independent type of cooperativity in porcine strain 41, while in bovine strain KVC-1, a positive type of cooperativity was observed.

Animals↗
PubMed1994

Antigens and glycoproteins of larvae, nymphs and adults of the tick Ixodes ricinus.

Protein components of homogenates of unfed larvae and nymphs of Ixodes ricinus (L.), and of ovary, haemolymph, Malpighian tubules, rectal ampulla, fat body, integument, salivary glands and midgut of partially fed adult females were studied for their antigenicity and carbohydrate moieties using immunoblotting and lectin affinity blotting (LAB) techniques. Comparing the individual anti-larval, anti-nymphal and anti-adult immune sera for their capacity to recognize the specific and trans-stadially cross-reactive antigenic proteins, larval feeding induced the most effective humoral response. The majority of immunogens recognized by rabbit anti-tick immune sera are glycoproteins. Most of the glycosylated antigens were modified with N-type glycans; however, O-type glycans were also demonstrated in some antigens. The correlation of the type of glycosylation with antigenicity, and the sharing of common antigenic epitopes by various tissues, are discussed.

Animals↗
PubMed1993

Characterisation of salivary gland antigens of Triatoma infestans and antigen-specific serum antibody response in mice exposed to bites of T. infestans.

In mice, the antigen-specific serum antibody response following exposure to bites of Triatoma infestans nymphs and adults was determined using enzyme-linked immunosorbent assay (ELISA). The second and the third exposure to T. infestans bites resulted in higher antibody levels than during the primary exposure. Antigen-specific antibody development was faster in mice exposed to bites of nymphs than in mice exposed to adults; however, a higher antibody level was found in mice bitten by adult bugs. Protein components of T. infestans saliva were characterised using electrophoretic and blotting techniques. The immunoblotting patterns were similar in mice exposed to insect bites of various developmental stages. Antigen-specific serum antibodies reacted only with high molecular mass components (two double bands of 100 and 120 kDa, and the 80 kDa antigen). The 80 kDa component was glycosylated. Affinity to lectin derived from Pisum sativum revealed the presence of a bi- or triantennary complex type of glycan. There were similar glycan structures in the main glycoprotein components of T. infestans saliva at 18-35 kDa; however, the components did not react with antibodies of mice exposed to insect bites.

Animals↗
PubMed1992

Characterization of Borrelia burgdorferi glycoconjugates and surface carbohydrates.

Borrelia burgdorferi glycoconjugates with different oligosaccharide structures were characterized by a blotting technique with peroxidase-labelled lectins. The localization of surface carbohydrates was studied using electron microscopy with lectin-gold complexes. A high-mannose glycan structure was detected in 83 kDa glycoprotein (major extracellular protein); at least four carbohydrates (glucose or mannose, galactose, N-acetylgalactosamine and N-acetylglucosamine) were present in other Borrelia glycoconjugates. N-acetylneuraminic (sialic) acid was detected on the Borrelia surface. Two sialidases with different specificities were used in an attempt to cleave off the Borrelia N-acetylneuraminic acid. The attempt was successful by using Vibrio cholerae sialidase which has a broad substrate specificity, while the mumps-virus sialidase with restricted substrate specificity had no effect. Endogenous activity of N-acetylneuraminidase was not demonstrated in B. burgdorferi K 5 and B 31 strains.

Animals↗
PubMed1992

Analysis of tick-borne encephalitis virus antigens by monoclonal antibodies.

Monoclonal antibodies (MAbs) against Central European tick-borne encephalitic virus, strain Hypr, were used for determination and characterization of viral antigens of infected PS cells. The MAbs reacted in immunoblotting with flavivirus glycoprotein E (56 kD), and nonstructural protein NS3 (70 kD). According to enzyme immunoassay with infected cells, NS3 antigen is expressed in the plasmalemma.

Animals↗
PubMed1991

Isolation and characterization of an immunogen from the louse Polyplax spinulosa.

The reaction of Polyplax spinulosa protein components with antigen-specific rat antisera and with five plant lectins is described. In immunoblotting, the antisera from rats infested with the louse P. spinulosa specifically recognized from 7 to 11 antigenic components of louse whole-body homogenates. Affinoblotting analysis with lectins showed that 10 of these components were glycoproteins with different types of glycan structure. Only one immunogenic antigen was isolated using immunoaffinity chromatography with the gammaglobulin fraction of an antigen-specific antiserum as immunospecific ligand. Further electrophoretic and immunochemical analyses revealed that it was a glycoprotein with relative molecular weight (RMW) 31 kDa and with high mannose type of oligosaccharide.

Animals↗
PubMed1991

Lectin binding analysis of Argas polonicus tissue glycoproteins.

Proteins of the Malpighian tubules (MT), midgut tissue (MG), salivary glands (SG), internal reproductive organs (RO), epidermis (EP), cerebral ganglion (CG), rectal ampulla (RA) and larval homogenate (LA) of Argas (Argas) polonicus were studied for their antigenicity and lecin affinity using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), immunoblotting, lectin affinoblotting and enzyme-linked lectin sorbentassay (ELLSA) techniques. A glycoprotein of 305 kDA was found in all tissues studied. All low molecular weight antigenic proteins recognized by anti-larval immune pigeon serum, except for one of 35 kDA, i.e. the 19-, 21-, 23-, 27-, 34-, and 46- kDa proteins, were shown to be glycoproteins. The glycosylation was shown to be N-linked in all of these antigens, but O-type glycosylation was also demonstrated in the 34-kDa glycoprotein. The correlation between the glycosylation and antigenicity of these proteins is also discussed.

Animals↗
PubMed1991

Interaction of tick/borne encephalitis virus with mouse peritoneal macrophages. The effect of antiviral antibody and lectin.

The interaction between tick-borne encephalitis (TBE) virus strain Hypr and mouse peritoneal macrophages was followed in vitro. Macrophages from juvenile mice (8-11 days old) were more permissive for virus infection than macrophages from adults (25-30 days old). Anti-TBE antibody in the subneutralizing dose increased the number of infected macrophages as well as virus release into the culture medium. Concanavalin A (con A), which bound to the virus as well as to the surface of macrophages, increased the uptake of the virus, but it neither enhanced the number of infected cells nor increased the virus release into medium. Antibody and lectin can modify the interaction between TBE virus and macrophages. Nevertheless, the Fc receptor-mediated endocytosis seems to be a necessary prerequisite for enhancing the effect of a ligand.

Aging↗
PubMed1991

Monoclonal antibodies to tick-borne encephalitis (TBE) virus: their use for differentiation of the TBE complex viruses.

Monoclonal antibodies (MoAbs) to Central European tick-borne encephalitis virus (strain Hypr) were used for differentiation of eight viruses of the TBE complex by indirect immunofluorescence. MoAb 11/B3 (in Western blot recognizing 52 and 70 kD polypeptides) reacted with five out of the eight TBE complex viruses, MoAb 13/E5 (anti-52 kD protein) reacted with the western or eastern subtype of TBE virus only, while MoAb 12/G4 (anti-70 kD protein) distinguished the western subtype of TBE virus from the rest of the TBE complex. These three MoAbs were able to differentiate the virulent strain Hypr from attenuated strains Skalica and Hy-HK-18-"3". MoAb 2/10C (anti-56 and 70 kD proteins) which reacted with all viruses of the TBE complex, recognized both virulent and attenuated strains of TBE virus.

Antibodies, Monoclonal↗
PubMed1991

[Antigens for the diagnosis of tick-borne encephalitis using the ELISA technique].

From the brains of suckling mice infected with the virus of tickborne encephalitis, strain Hypr, the authors concentrated by precipitation with polyethylene glycol - 6000 and purified by differential ultracentrifuging on a linear saccharose gradient the virion antigen KEV-II for assessment of specific human antibodies, using the indirect ELISA technique. The antigen was characterized as to haemagglutination activity, electrophoretic properties, immunoblotting with a monoclonal antibody against external layer gpE and enzyme immune analysis to assess the relative ratio of gpE in the diagnostic antigen. Using the technique of indirect ELISA with antigen KEV-II, the authors examined in 1988 and 1989 sera of 631 patients with a specificity of estimations of 99.4% (0.6% falsely positive results) and sensitivity expressed by the liminal serum dilution rate of 1:1000.

Antigens, Viral↗
PubMed1990

Artificial immunization of pigeons against Argas polonicus (Ixodoidea, Argasidae).

Two subcutaneous injections of salivary gland antigen (SGA) or larval homogenate (LH) at 2-week intervals induced a resistance in pigeons to Argas (Argas) polonicus Siuda, Hoogstraal, Clifford and Wassef larvae and induced anti-tick antibodies. The number of larvae rejected after LH immunization was significantly higher compared to SGA immunization but lower than the number of larvae rejected after two natural infestations at 2-week intervals. The antibody titre reached a peak on day 6 following the first inoculation of LH, and 11-13 days after SGA inoculation. The maximum antibody titre was recorded 6 days after a second challenge for both antigens. The highest antibody titre was reached after the first inoculation with LH but only after the second inoculation with SGA. The sera of pigeons immunized either with SGA or LH cross-reacted with the other antigen as demonstrated by ELISA. SDS-PAGE and immunoblot studies demonstrated several differences in the protein profiles of these antigens, the presence of 34 and 35 kdal proteins in SGA and their absence in LH.

Animals↗
PubMed1990

An attempt to analyse the functional difference between various mumps virus strains.

Enzymatic activity of N-acetylneuraminidase of ten various strains of mumps virus was compared. From the viewpoint of their biological properties, these strains could be classified as laboratory, neurovirulent, and vaccinal (attenuated) ones. The enzymatic activity was evaluated by Scatchard's plot which enables to interpret it according to polarity of the cooperativity of enzymes' binding sites. Laboratory strains of the mumps virus demonstrated an independent type of cooperativity, while vaccinal (attenuated) ones showed a positive type of cooperation.

Binding Sites↗
PubMed1990

Antigenic characterization of rat louse Polyplax spinulosa.

Number and relative molecular weights of proteins in whole body homogenates of the louse, Polyplax spinulosa were determined using SDS-PAGE. 13 protein components from the total of 28 bands were defined as Con A binding glycoproteins. In immunoblotting sera of lice infested laboratory rats of BN strain specifically recognized 3 major protein components with r.m.w. of 77,000, 105,000 and 230,000 Da and from 6 to 8 minor protein components with r.m.w. of 31,000-180,000 Da.

Animals↗
PubMed1989

Antibody-mediated response of pigeons to Argas polonicus larval feeding and characterization of larval antigen.

Circulating antibodies to larval Argas polonicus antigen detected in the blood of pigeons by means of ELISA reach their highest level 3-6 days post-tick attachment. During 6-8 days post infestation when most larvae detach from their host, there is an abrupt drop of the antibody level in blood followed by second peak at day 10-15. During the secondary and subsequent infestations the dynamics of the antibody production is analogous, but the maximum absorbance values found are higher with each following infestation. This is in direct correlation with the growth of immune resistance of hosts. The transfer of immunoglobulins of resistant pigeons produces in naive hosts a partial resistance in a statistically significant (P less than 0.01) reduction of the number of engorged larvae, in the shortening of larval feeding period and in the decrease of their mean weight after feeding. However this resistance was significantly (P less than 0.01) less expressed than in naturally resistant pigeons during secondary infestation. The protracted effect on the duration of premoulting period and the percentage of moulted larvae manifested in larvae after secondary infestation was not apparent in molecular weight of approximately 19, 21, 23, 27, 45 and 165 kilodaltons, were recognized by serum of resistant pigeons.

Animals↗
PubMed1988

Contribution to laboratory diagnosis of mumps and parainfluenza.

Specific IgM and IgG antibodies to mumps virus (MV) were detected in sera of mumps-patients by ELISA in agreement with the results obtained by indirect immunofluorescence (IF). Of given sera 37.5% contained IgM reacting in indirect ELISA also with the antigens of parainfluenza virus (PiV) T3. In all patients with respiratory illness over 2 years of age, the significant increase of antibodies to PiV in haemagglutination inhibition (HI) test was in good correlation with serum IgM and IgG antibody levels to PiV T3 determined by ELISA; but, in addition, 30.7% of these sera cross-reacted with MV antigens. The cross-reactions were eliminated by using MV-nucleocapsid antigen in indirect ELISA, or in direct ELISA using the peroxidase-labelled whole virion antigen. In some children under two years of age a discrepancy was observed between the significant increase of serum antibodies in HI and the inability to detect specific IgM antibodies by means of ELISA in their sera. The low-avidity antibodies appearing after primary PiV infection were probably washed off during the ELISA procedure.

Antibodies, Viral↗
PubMed1988

Rapid serological diagnosis of tick-borne encephalitis by means of enzyme immunoassay.

A system of IgM-capture EIA made up from Czechoslovak immunopreparations (SEVAC) was developed for a rapid serological diagnosis of tick-borne encephalitis (TBE). The method was tested on clinical material. The total IgM antibody titres were detected using pig antiserum and the selection of specific IgM antibodies was made with TBE antigen with following indirect way of detection. The antibody analysis made by means of this method is sensitive and fully conforms to the clinical picture of the disease.

Animals↗
PubMed1988

Isolation of TBE virus from the tick Ixodes hexagonus.

Tick-borne encephalitis (TBE) virus was isolated from a sample of Ixodes hexagonus ticks collected from the hair of the western European hedgehog (Erinaceus europaeus) which had been captured on the edge of a new housing estate in Ceské Budĕjovice at the end of September 1986. This was the first isolation of TBE virus from this vector, supporting the previous experimental results. The virus was identified in immunofluorescent and plaquereduction neutralization tests.

Animals↗