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A Vögtlin

Publications and source records attributed to A Vögtlin.

5 recordsLinked to original sources

Reverse transcription real-time PCR assays for detection and quantification of Borna disease virus in diseased hosts.

Borna disease is a severe, immunopathological disorder of the central nervous system caused by the infection with the Borna disease virus (BDV). The detection of BDV in diseased animals, mainly sheep and horses, is achieved by histological, immunohistochemical and serological approaches and/or PCR-based technologies. In the present study, reverse transcription, real-time PCR assays were established for the detection of BDV in the brain tissue from sheep and horses, using loci for the p40 (nucleoprotein) and the p24 (phosphoprotein) genes. The PCRs were equally specific and sensitive, detecting 10 target molecules per reaction and one BDV-infected cell among 10(6) non-infected cells. In tissues from BDV-diseased sheep and horses, the p24 target was detected at higher abundance than for p40. Therefore, the p24 test is suggested to be of higher value in the diagnostic laboratory. However, both assays should be useful for addressing questions in pathogenesis and for detecting BDV reservoirs in endemic areas.

Animals↗

HSV-1-based amplicon particles are able to transduce cells of feline origin with genes encoding biologically functional feline IL-10 or IL-6.

The most common viral disease of cats worldwide is the infection with feline herpesvirus 1 (FeHV-1). This infection may be followed by Herpetic stromal keratitis (HSK), which is supposed to have an immunopathological basis. Experiments using herpes simplex viruses (HSV) in mouse models indicated that HSK may be treated by topical application of the interleukin 10 (IL-10) gene. The objective of this study was the construction of human herpes simplex virus type 1 (HSV-1)-based amplicon vectors expressing feline interleukin genes and delivery of these genes into cells of feline origin. HSV-1-based amplicon vectors encoding either the enhanced green fluorescent protein, the feline IL-6 or the feline IL-10 under control of the HSV-1 immediate-early 4/5 promotor were constructed, packaged into amplicon particles, transduced into feline cells, and tested for RNA synthesis and biological activity. Feline cells were successfully transduced by HSV-1-based amplicon particles and RNA specific for the transgene was detected already at 2h post transduction, with a maximum at 24h. The recombinant feline IL-10 was functionally active as demonstrated by the reduction of both IL-12 p40 and interferon-gamma-mRNA production in Pansorbin stimulated feline peripheral mononuclear cells. Similarly, the recombinant feline IL-6, which was secreted into the supernatant of transduced cells, was able to support the growth of the IL-6-dependent murine B cell hybridoma 7TD1. HSV-1-based amplicon particles are able to transduce cells of feline origin with genes encoding biologically functional feline IL-10 or IL-6. It will be of high interest to study the effects of these tools in vivo.

Animals↗

Quantification of feline herpesvirus 1 DNA in ocular fluid samples of clinically diseased cats by real-time TaqMan PCR.

A fluorogenic PCR was established for the quantification of feline herpesvirus 1 (FeHV-1) DNA in ocular fluid samples of clinically diseased cats. The new assay was specific for FeHV-1 and sensitive. The 100% detection rate ranged from 0.6 to 6 50% tissue culture infective doses per sample. When spiked samples with known quantities of virus were used, infectious virus titers and quantification of viral DNA by PCR correlated to each other in a linear fashion (R(2) = 0.9858) over a range of 4 orders of magnitude. Within this range, it was possible to calculate the FeHV-1 DNA content from a given infectious dose, and vice versa. The new diagnostic procedure was applied to ocular fluid samples from cats experimentally infected with FeHV-1 and specific FeHV-1-free cats. A good correlation between virus titer and quantitative PCR was observed, although only early in infection. In a second stage, the titer of infectious virus collapsed, while the PCR signal remained high. A constantly decreasing PCR signal accompanied by negative virus isolation was characteristic for a final stage of the infection. Finally, clinical samples from 20 cats that were suspected to suffer from FeHV-1 infection were analyzed. By comparing virus titers and quantitative PCR signals, it was possible to determine the current stage of the ongoing infection. Based on these findings, comparison of the results of consecutive samples allows the tracking of the course of the infection. Therefore, the new method combines the advantages of the two previously established conventional methods, qualitative PCR and virus isolation and titration.

Animals↗

Feline eosinophilic conjunctivitis.

OBJECTIVE: To review 12 cases of histologically confirmed feline eosinophilic conjunctivitis, their clinical, cytologic, histologic and electronmicroscopic findings, results on PCR for FeHV-1, treatment and outcome. ANIMALS STUDIED: Twelve naturally occurring cases presented during a period of 26 months. PROCEDURES: Thorough ophthalmologic examination, conjunctival scrapings performed with the cytobrush method; histologic samples from the palpebral conjunctiva; PCR for FeHV-1 on Schirmer Tear Test (STT) strips; saliva and nasal swabs, and retrospective evaluation of all results. RESULTS: The breed most commonly affected was the Domestic Shorthair (n = 8), followed by Persians (n = 2), Somali (n = 1) and Siamese (n = 1). Age at presentation was 1-15 years with a mean age of 7.2 years. Nine cats were castrated males; three cats were females: two of them were spayed. Unilateral (n = 7) or bilateral (n = 5) involvement with depigmentation and erosions of lid margin, blepharospasm, swelling and redness of conjunctiva and third eyelid were the most common clinical findings. Frequency of eosinophils in cytologic samples was more than 10% in every patient. PCR for FeHV-1 on STT was negative in all cases. Histologically, eosinophils, lymphocytes, plasma cells, mast cells and macrophages were involved. On electronmicroscopy, viral particles were not detected. Ten cases needed long-term anti-inflammatory treatment. CONCLUSIONS: The 12 reviewed cases suggest that feline eosinophilic conjunctivitis is a chronic inflammatory uni- or bilateral disease of the adult cat. Typically the lid margin was also involved, and was thickened, depigmented and erosive. Cytological examination of conjunctival scrapings was a valuable tool for detecting eosinophilic conjunctivitis. The cytological findings correlated well with the histopathological findings in our patients. Topical or systemic anti-inflammatory drugs resolved the clinical symptoms in our cases within a short period of time. Neither electronmicroscopy nor PCR were able to detect involvement of FHV1 in the represented cases. The etiopathogenic role of FeHV-1 remains undetermined.

Animals↗

Use of polymerase chain reaction (PCR) for the detection of vaccine contamination by infectious laryngotracheitis virus.

Quality control of biologicals for veterinary use includes certification of freedom from extraneous agents. Contamination of vaccines may originate from various materials used for production and during manufacturing process. Requirements for avian virus vaccines to demonstrate freedom of adventitious agents are stated in the European Pharmacopoeia and include monitoring for infectious laryngotracheitis virus (ILTV). ILTV is an avian herpesvirus belonging to the alphaherpesvirus subfamily causing acute respiratory disease. To date the methods to detect ILTV contaminating biologicals consist of demonstration of antibody induction in chicken after immunization or virus cultivation in embryonated eggs. These methods are time consuming and laborious. Therefore, a specific, simple and sensitive in vitro polymerase chain reaction (PCR) for the detection of ILTV contamination in avian virus vaccines was developed. Primers were designed to amplify part of the p32 gene. Four different ILTV vaccine strains could be unequivocally detected. The identity of the amplified fragment was confirmed by restriction endonuclease analysis.

Animals↗