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V Moennig

Publications and source records attributed to V Moennig.

At least 37 records · Page 2Linked to original sources
PubMed2000

An actin-binding protein is involved in pestivirus entry into bovine cells.

Infection of bovine cells with bovine viral diarrhoea virus (BVDV) can be blocked by the monoclonal antibody (mab) BVD/CA 26, which is directed against a cellular membrane protein. To characterize this molecule, it was isolated and purified by column chromatography. It was found to be an acidic, glycosylated membrane protein consisting of two polypeptide chains of about 28 and 56 kDa. Under non-reducing conditions the chains formed multimers of about 200 kDa. In an actin binding assay the 56 kDa polypeptide chain bound to F-actin as judged by co-sedimentation with actin filaments. Since the target molecule of BVD/CA 26 is localized on the surface of living cells and additionally binds to F-actin, a possible biological function may be to connect the cortical actin filaments with the cellular plasma membrane. The blocking effect of BVD/CA 26 indicates that this cellular plasma membrane protein is involved in the endocytic pathway of BVDV particles.

Actins↗
PubMed2000

[Werner Schäfer. A life as researcher and teacher].

The following short biography recalls Professor Dr. Dr. h.c. Werner Schäfer, emeritus professor and director of the Medical Biology Department of the Max-Planck-Institut für Virusforschung in Tübingen and scientific member of the Max-Planck Society who died on 25th April 2000. He was one of the most distinguished pioneers of animal virology and one of the great personalities who since the Second World War have helped German science to regain its international reputation. In a brief synopsis the important results of his work on the viruses he used as models to conduct his research have been portrayed. As a result of Schäfer's scientific conception to gain insights into the functional characteristics of viruses by looking at their structure, the field of virology has taken new directions and founded a school whose pupils try to continue his successful and much honoured life's work.

Education, Veterinary↗
PubMed2000

[New fundamental order of the School of Veterinary Medicine Hanover].

On June 29, 2000, the Council of the School of Veterinary Medicine Hannover (TiHo) passed a new fundamental order. Upon termination of the current terms of office of the rector and the chancellor in September and at the end of the year 2001, respectively, a school management will be established with a longer term of office and a new type of School Council. However, the new fundamental order must still be approved by the Lower Saxony Ministry of Science and Culture. This change has been made necessary by radical restructuring affecting all universities in Lower Saxony: the transformation to a state enterprise with the concomitant introduction of a global budget demands full-time management. This is a step of historical significance, for this change in the fundamental order puts an end to a tradition of 87 years at the School of Veterinary Medicine Hannover under a constitutional rectorate. The following essay describes the most important changes and explains their necessity.

Faculty↗
PubMed1999

Rapid and sensitive detection of immunoglobulin M (IgM) and IgG antibodies against canine distemper virus by a new recombinant nucleocapsid protein-based enzyme-linked immunosorbent assay.

Canine distemper morbillivirus (CDV) infection causes a frequently fatal systemic disease in a broad range of carnivore species, including domestic dogs. In CDV infection, classical serology provides data of diagnostic and prognostic values (kinetics of seroconversion) and is also used to predict the optimal vaccination age of pups. Routine CDV serology is still based on time- and cost-intensive virus neutralization assays (V-NA). Here, we describe a new capture-sandwich enzyme-linked immunosorbent assay (ELISA) that uses recombinant baculovirus-expressed nucleocapsid (N) protein of a recent CDV wild-type isolate (2544/Han95) for the detection of CDV-specific antibodies in canine sera. Recombinant antigen was produced with high efficacy in Heliothis virescens larvae. The capture-sandwich ELISA enabled a clear-cut qualitative evaluation of the CDV-specific immunoglobulin G (IgG) and IgM serostatuses of 196 and 35 dog sera, respectively. Inter-rater agreement analysis (kappa = 0.988) indicated that the ELISA can be used unrestrictedly as a substitute for the V-NA for the qualitative determination of CDV-specific IgG serostatus. In an attempt to semiquantify N-specific antibodies, a one-step-dilution (alpha method) IgG-specific ELISA was implemented. Alpha values of >/=50% showed very good inter-rater agreement (kappa = 0.968) with V-NA titers of >/=1/100 50% neutralizing dose (ND50) as measured against the central European CDV wild-type isolate 2544/Han95 in canine sera originating from northern Germany. An ND50 titer of 1/100 is considered a threshold, and titers of >/=1/100 indicate a resilient, protective immunity. CDV N-specific antibodies of the IgM class were detected by the newly developed ELISA in 9 of 15 sera obtained from dogs with symptoms of acute distemper. In leucocytes of 5 of the 15 dogs (all of which were also IgM positive) CDV RNA was detected by reverse transcription (RT)-PCR. The recombinant capture-sandwich ELISA detecting N-specific antibodies of the IgG class provided superior sensitivity and specificity and thus represents a rapid and cost-effective alternative to classical CDV V-NA. By detection of specific IgM antibodies, the ELISA will be complementary to RT-PCR and V-NA in the diagnosis of acute distemper infections.

Animals↗
PubMed1998

Experimental induction of mucosal disease: consequences of superinfection of persistently infected cattle with different strains of cytopathogenic bovine viral diarrhea virus.

Mucosal disease (MD) can be induced in cattle persistently infected with noncytopathogenic bovine viral diarrhea virus (ncp BVD virus) by superinfecting them with antigenically related cytopathogenic (cp) BVD virus strains. While some of these animals succumb to early onset MD after 2 to 3 weeks post infectionem (p.i.), others only react by producing neutralizing antibodies against the cp BVD virus strain and may develop late onset MD after longer incubation periods. The aim of this study was to determine if an increasing degree of antigenic homology between the ncp and the superinfecting cp BVD virus strains as determined by their comparative reactivity with E2 glycoprotein specific monoclonal antibodies (mabs) increases the probability of inducing early or late onset MD, respectively. For this, each two of eight clinically healthy animals from the same herd and persistently infected with the same ncp BVD viruses were superinfected with four different cp BVD virus strains. As only two of these animals developed late onset MD, one animal from a different herd that developed early onset MD was included in the study. Besides clinical observation and testing for antibody production, virus isolation and characterization of the cp BVD virus isolates were performed. The results indicate that antigenic similarity as determined by comparative mab analysis alone is not sufficient to allow prediction of the outcome of the disease.

Amino Acid Sequence↗
PubMed1998

Application of a computer program for genetic typing of classical swine fever virus isolates from Germany.

The commercial software program HLA SequiTyper (Amersham Pharmacia Biotech), designed originally for human leukocyte antigen typing, was adapted for rapid typing of classical swine fever (CSF) virus isolates. The program compares new sequence data with those stored in a database file and calculates the most probable assignment. For generating the CSF virus sequence database, 150 bp of the 5' nontranslated genomic region (5'-NTR) from 88 German classical swine fever virus isolates from outbreaks between 1984 and 1997 were solid-phase sequenced directly after RT-PCR amplification. Sequence alignments showed that they all belonged to the previously defined genetic group 2. Within this group, six different subgroups could be distinguished, and were designated according to the geographic location where they are either still endemic or where they appeared most commonly. The advantage of using the HLA SequiTyper program is that it reads directly the sequence files as generated by the ALF sequencer (Amersham Pharmacia Biotech), making any manipulations unnecessary. In addition, a constant quality control of the raw sequence data can be achieved, as more than one sequence from the same isolate can be evaluated at once. Using this approach, new CSF isolates can be typed within 2 days.

Animals↗
PubMed1998

Genetic analysis of the central untranslated genome region and the proximal coding part of the F gene of wild-type and vaccine canine distemper morbilliviruses.

Located between the open reading frames encoding the matrix (M) and the fusion (F) protein the morbillivirus genome contains an unusually large non-coding intercistronic region (M-F UTR) of up to 5.6% of the full length genome. Any function(s) of this region have largely remained obscure. Here, we analyze the M-F UTR and the proximal coding part of the downstream F gene of several recent canine distemper morbillivirus (CDV) wild-type (wt) isolates and vaccine strains. While the F gene coding part appeared to be highly conserved (about 93% homology), a considerable degree of strain-specific variation of up to 21.4% was evident when comparing the M-F UTR. Phylogenetic analysis revealed a co-circulation of several contemporary CDV genotypes within a close geographic range (central Europe). A remarkably distinct CDV wt lineage, so far detected only in mustelids, is displayed. A rather non-scattered pattern of mutations within the M-F UTR suggested superimposition of RNA sequence and/or secondary structure constraints. Extensive folding in the long (460 nt) and moderately GC-rich 5'-UTR of the F mRNA was evident, particularly around the putative F protein translation initiation codon (AUG461 of the Onderstepoort vaccine strain). The region immediately preceding the putative F initiation site also harbored the only mutation unique to both vaccine strains within the F-5'UTR (position 455: Awt vs. Cvac). The putative F protein start codon, AUG461, was found to be mutated to AUA or GUA in all wt isolates analyzed and in another vaccine strain (Rockborn). Possible consequences for F protein translation initiation in wt CDV are discussed.

Animals↗
PubMed1998

[Cytopathogenic bovine viral diarrhea viruses induce apoptosis in bovine cell cultures].

The pestivirus bovine viral diarrhea (BVD) virus is the causative agent of Mucosal Disease (MD) of cattle. From persistently infected animals, only the non-cytopathogenic biotype BVD virus can be isolated. Cattle succumbing to MD additionally harbour cytopathogenic BVD virus. While cp BVD virus isolates induce a cytopathic effect (cpe) in susceptible monolayer cell cultures, infection with ncp BVD virus isolates has no visible effect. The purpose of this study was to investigate the correlation between cpe and apoptosis.

Animals↗
PubMed1998

[Clinical-virologic course after superinfection of persistently infected cattle with cytopathogenic bovine viral diarrhea virus strains].

Vaccination with live cytopathogenic (cp) bovine viral diarrhoea virus (BVDV) is often used for control of this disease. In animals which are persistently infected with noncytopathogenic (ncp) BVDV this can lead to the outbreak of mucosal disease (MD). To simulate vaccination of such animals and to monitor the clinical-virological course after superinfection, nine clinically healthy calves which were persistently viremic were superinfected with different cp BVDV strains. One animal succumbed to early onset MD within three weeks after superinfection. During the observation period of 18 months four animals developed severe clinical signs. While two animals developed late onset MD, the other two had to be euthanized due to clinical signs which could not be related to the superinfecting BVDV. These results indicated that after superinfection or vaccination of persistently infected calves with cp BVDV the probability of developing early and/or late onset MD is significantly increased. The risks arising from uncritical vaccination of herds with unknown virological status in relation with the control of BVDV conforming to the actual official guidelines are discussed.

Animals↗
PubMed1997

The development of early vs. late onset mucosal disease is a consequence of two different pathogenic mechanisms.

Bovine viral diarrhea (BVD) virus is the causative agent of fatal mucosal disease (MD) of cattle. Experimental induction of MD can be achieved by superinfection of calves persistently viremic with a noncytopathic (ncp) BVD virus using an antigenically similar cytopathic (cp) BVD virus. Here we describe the characterisation of BVD viruses isolated from three cases of experimentally induced MD. One animal developed clinical symptoms two weeks after superinfection (early onset MD), while the onset of disease in the other two cases occurred with a delay of months (late onset MD). Antigenic characterisation of the viruses was performed using a panel of monoclonal antibodies against the E2 glycoprotein. For genetic analysis, RT-PCR was applied to amplify specific insertions and duplications in the NS2-3 genomic region of the cp BVD viruses. In addition, these amplicons and fragments of the viral E2 genes were sequenced. The results showed that in the case of early onset MD the cp BVD virus isolated after begin of disease was identical to the one used for superinfection. In contrast, the cp BVD viruses isolated from the two animals with late onset MD were obviously the result of genetic recombinations between the persistent ncp and the superinfecting cp BVD viruses. We conclude that early and late onset MD are the consequence of different pathogenic mechanisms.

Amino Acid Sequence↗
PubMed1997

[Transmissible spongiform encephalopathies].

Transmissible spongiform encephalopathies are a unique group of brain diseases of different animal species and man that can be transmitted between individuals by inoculation or ingestion of diseased nervous system tissues. The causative agents induce non inflammatory spongiform degeneration of the central nervous system which leads to a progressive loss of brain function including ataxia and paralysis resulting always in death. The agent might consist only of a conformationally altered cellular protein of the host species devoid of nucleic acid. The natural occurrence of transmissible spongiform encephalopathies is restricted to a few species. Thus, under certain conditions, i. e. the feeding of infectious bone meal or scientific experiments, the agents can be transmitted to other species causing lethal disease.

Animal Feed↗
PubMed1997

[Comparison of different BVD virus strains for their use in the differential diagnosis of classical swine fever--an attempt to standardize neutralization tests].

Six bovine virus diarrhoea (BVD) virus strains were tested in the neutralization test for their use in the differential diagnosis in classical swine fever (CSF) serology. The aim of the investigation was to find a suitable BVD virus strain guaranteeing a safe differentiation of CSF- and BVD virus induced antibodies using permanent cell cultures (PK-15, MDBK). For test purposes the neutralizing antibody titres of 73 defined test sera were titrated against the CSF virus strain Alfort/187 as well as the BVD virus strains Grub, Paplitz, NADL, 1138/69, Stendal, 10421/Han 94). Tests were repeated fivefold. The level of mean antibody titres, the differences in titre to the homologous pestivirus strain, the standard deviation and the variation coefficient served as test criteria. The BVD virus strains Grub and NADL yielded the best results. In view of harmonization and standardization the BVD virus strain NADL in connection with a standard protocol for neutralization tests is recommended for the differential diagnosis in CSF serology. Due to the adaptation of the permanent cell-lines PK-15 and MDBK to horse serum a further source of contamination with non cytopathogenic BVD viruses under routine conditions can be excluded.

Animals↗
PubMed1995

Identification of cell membrane proteins linked to susceptibility to bovine viral diarrhoea virus infection.

Three monoclonal antibodies directed against cell surface molecules of bovine cells inhibited subsequent infections with bovine viral diarrhoea virus (BVDV). They specifically blocked the infectivity of three non-cytopathogenic and three cytopathogenic BVDV strains. These results showed that an important mechanism for virus uptake was inhibited. The ligand of the monoclonal antibody BVD/CA 17, which blocked infectivity most efficiently, was found on leukocytes from a wide range of domestic and wild even-toed ungulates using flow cytometric analysis. In contrast, the monoclonal antibodies BVD/CA 26 and BVD/CA 27 appeared to be specific for bovine cells. Immunoprecipitation of labelled bovine cell surface proteins showed that the three monoclonal antibodies bound to proteins with identical relative molecular masses (M(r)). Proteins of an apparent M(r) of 93 K and 60 K were precipitated from lysates of fetal bovine kidney cells irrespectively of the MAbs used.

Animals↗
PubMed1995

Spot synthesis of overlapping peptides on paper membrane supports enables the identification of linear monoclonal antibody binding determinants on morbillivirus phosphoproteins.

In order to map antigenic domains on the P-protein of morbillivirus, a series of overlapping peptides, representing the P-protein sequences of phocid distemper virus strain 2558/Han88 and canine distemper virus strain Onderstepoort, were synthesized on a paper support by the spot-technique. The reactivity of six monoclonal antibodies with the peptides was tested in an enzyme immunoassay and compared to their reactivity in Western blots and in an ELISA using detergent extracts from virus-infected cells. Three linear determinants could be localized on the P-protein. Two antibody-binding sites were delineated within the C-terminal (between amino acids 307-322 and 382-400, respectively), and a third one was located on the N-terminal part (amino acids 13-31) of the protein. Fine mapping of this binding site revealed that this was a part of an antigenic domain. In Western blots, the monoclonal antibodies reacting with this domain also reacted with a second protein which was possibly the V-protein.

Amino Acid Sequence↗
PubMed1995

Experimentally induced "late-onset" mucosal disease--characterization of the cytopathogenic viruses isolated.

Antigenic and genetic analyses were performed in order to establish relationships between the noncytopathogenic (ncp) and the cytopathogenic (cp) bovine viral diarrhoea viruses (BVDV) involved in the induction of a case of experimentally induced "late-onset" mucosal disease (MD) symptoms. The persistent ncpBVDV, the cpBVDV used for superinfection (strain TGAC) and the virus isolates from faeces (cpX) were examined using an immunoplaque test (IPT) to distinguish between cp and ncp virus populations. The cp populations were cloned by plaque purification and found to be free of ncpBVDV when using the IPT. The cpBVDV clones and the persistent ncpBVDV were analysed in an enzyme immunoassay on heat-fixed infected cells (IM-EIA) and in a neutralization test using a panel of 27 monoclonal antibodies against the E0 (gp48) and E2 (gp53) viral glycoproteins. It was found that strain TGAC contained two antigenically distinct subpopulations of cpBVDV (TGAC-B1 and TGAC-B2). The endogenous ncpBVDV and the cpX clones had the same reactivity pattern in both tests. In addition, p80 gene duplications in the genomes of the cpBVDV clones were analysed using the polymerase chain reaction and subsequent restriction enzyme analysis of the amplicons. The clones analysed from TGAC-B1 and those from cpX had gene duplications of identical sizes showing the same restriction enzyme patterns. Our results suggest that the cpBVDV which finally lead to "late-onset" MD arose by recombination and/or by mutations of the cpBVDV used for superinfection.

Animals↗
PubMed1995

Pathogenesis of intrauterine infections with bovine viral diarrhea virus.

BVDV shares with other Pestiviruses the ability to cross the placenta of pregnant host animals. The effects of fetal infections are complex and depend on a number of factors, e.g., age of the zygote/embryo stage, no infection seems to occur. During the last one third of gestation the infection is terminated by the ontogeny of the fetal immune system. This leaves a window of susceptibility during early stages of fetal development allowing establishment of viral persistence and/or the development of a number of fetopathologic effects. Additionally, fertility problems and abortions are observed. Calves that are born immunotolerant to BVDV and persistently viremic display a wide variety of abnormalities. However, there is an unknown proportion of calves born without any clinical signs indicative of persistent infection. The time of fetal infection during the first stages of pregnancy seems to play a crucial role with respect to the lesions induced. Generally, early infections seem to induce less damage compared with late infections, suggesting an indirect, possibly immune-mediated pathogenesis. Additionally, direct virus-cell interactions may play a role. Few data exist about the influence of differences in viral virulence on fetal pathology. Likewise the role of the viral target cell range is not clear.

Animals↗