Evaluation of the detection proficiency of laboratories testing of mammalian orthoreovirus 3 antibody in laboratory mice / 中国实验动物学报

Objective Through the proficiency validation of testing of mammalian orthoreovirus 3 (Reo3)antibody in laboratory mice, to investigate the capacity of experimental animal quality control laboratories, so as to improve the de-tection capacity.Methods According to the program approved by CNAS, serum samples after calibration were tested for stability and homogeneity, and numbered randomly.The random samples were issued to the participant laboratories with the Standard Operation Procedure( SOP) .The participants must submit the test reports and original records in time.The feed-back results were judged by the concordance rate with the anticipated results.Results 27 laboratories from 17 provinces were enrolled in this evaluation project, all of them submitted detection results on time.Results All the 27 laboratories were marked as pass or excellent, with a pass rate of 100%.ELISA was used in 26 laboratories, and immunofluorescence assay was used in one laboratory.Conclusions The ability for detection of Reo3 antibody in laboratory mice in animal test laboratories is high.The implementation of proficiency testing can reflect the inspection level of quality control laborato-ries.

Isolation and identification of two different genotypes of Tupaia orthoreoviruses / 中国实验动物学报

Objective To isolate and identify viruses from fecal samples of tree shrew with diarrhea.Methods Fecal sample supernatant of tree shrew with diarrhea was inoculated to three cell lines ( Vero, LLC-MK2 and KMB17 ) , and the cytopathic effects on the cells were observed.The infectious particles in the culture supernatant were further ana-lyzed by transmission electron microscopy ( TEM) , genomic RNA-PAGE, rotavirus detection kit, amplification of S1 com-plete segment and bioinformatics analysis.Results Constant cytopathic effects were induced in Vero, LLC-MK2 and KMB17 cell lines after three passages of culture.The results from TEM, RNA-PAGE and rotavirus analysis indicated that they belong to reoviruses.Analysis of the S1 segments revealed that the S1 sequence from KMB17 cell culture had the high-est homology with that of prototype isolate T1L (85%nucleotide homology and 90%amino acid homology), therefore this isolate was named as type I reovirus.The other two S1 sequences from LLC-MK2 and Vero cell culture were identical to have 85%nucleotide homology and 92%amino acid homology with the prototype isolate T3D, named as type III reovirus. Phylogenetic analysis indicated that the isolates in this study are evolutionally adapted to tree shrews.Conclusions It is the first report here that 2 genotypes of Tupaia orthoreovirus are isolated and identified from one fecal sample via three cell lines and viral S1-specific primers, which provides useful guidelines for the isolation and identification of other reoviruses from tree shrew or other hosts.

Establishment and application of a RT-nPCR assay for detection of orthoreovirus in tree shrews / 中国比较医学杂志

Objective To establish a reverse transcription nested polymerase chain reaction ( RT-nPCR ) assay for detection of tree shrews orthoreovirus (TRV).Methods Three strains of TRV were respectively isolated from fresh feces of three tree shrews that came from the same field at different times .We designed and synthesized two pairs of MRV L1 gene nested primers and established the system of RT-nPCR.The TRV RNA was extracted and reversely transcribed to cDNA as a template for nested-PCR amplification.The developed RT-nPCR was optimized.The specificity and sensitivity were tested.Finally, the RT-nPCR was used to detect TRV in 25 tree shrew samples.Results Taking the genomic RNA of TRV as template, the RT-nPCR was able to amplify a specific fragment band targeting the L 1 gene, while there were no target bands in the normal cell control , ( Wa strain rotavirus , hepatitis A virus , and herpes simplex virus ) .The RNA of TRV was diluted by 1:10 to 1:109 .Each dilution sample was analyzed by the RT-nPCR.The minimum detectable concentration of RNA was 0.01 pg/μL.The results of RT-nPCR detection showed that 4 of the 15 tree shrews were TRV-positive in the survival group , and 10 of 10 tree shrews were TRV-positive in the death group . Conclusions The RT-nRCR assay established in this study is accurate , specific and sensitive .Therefore, it can be used for routine detection of TRV in quality assurance testing .

Identification of two cytopathogenic agents, Mycoplasma hyorhinis and mammalian orthoreovirus 3 based on modified particle associated nucleic acids PCR / 대한수의학회지

Swine diseases could be caused by unrecognized or minor pathogens. In this study, two unknown cytopathogenic agents were isolated from swine, through cell culture. In order to identify these two cytopathogenic agent (designated CP129 and #2045-7), a particle associated nucleic acids PCR (PAN-PCR) from previous paper was used with simple modification. The cloning procedure was more specified in this study by adding cell control system. According to the modified PAN-PCR, two and four agents-specific DNA sequences were obtained from CP129 and #2045-7, respectively, and they were identified as Mycoplasma (M.) hyorhinis and Mammalian orthoreovirus by nucleotide BLAST. Since M. hyorhinis (CP129) was filterable and non-visible by microscope, this unusual virus-like nature of M. hyorhinis (CP129) was discussed. Especially, the reovirus (#2045-7) was a serotype 3 and a triple reassortant among three serotypes of reoviruses. It was grouped with recently reported reoviruses from disease cases (swine, human and feline), based on the genetic analysis of L1 and S1 partial sequences. In conclusion, two unknown cytopathogenic agents were successfully identified using modified PAN-PCR with cell control system and they were characterized in this study.