OBJECTIVEEvaluation of the direct rapid immumohistochemical test (DRIT) for laboratory surveillance of rabies.

METHODS72 brain specimens of domestic dogs or patients collected from Guizhou, Guangxi, Hunan, Anhui, Jiangsu and Yunnan provinces were detected by conventional methods including Direct Fluorescent-antibody Assay (DFA) and Reverse Transcription Polymerase Chain Reaction (RT-PCR), and by DRIT which was newly developed in the Rabies Section of the Centers for Disease Control and Prevention in the United States. The sensitivity and specificity of DRIT were evaluated by compare of the three results. By analysis of the index including cost of experiment, technique requirement and so on, the advancement and applicability of DRIT were discussed.

RESULTSCompared with DFA and RT-PCR, DRIT will be more applicable for laboratories with limited funds and weak techniques because of its lower cost needed and simpler techniques required while its sensitivity and specificity are equal to the other two methods.

CONCLUSIONDRIT is more valuable in rabies diagnosis and more applicable for extension and popularization in rabies laboratory surveillance in local CDC.

Animals ; Brain ; virology ; China ; epidemiology ; Dog Diseases ; diagnosis ; epidemiology ; virology ; Dogs ; Fluorescent Antibody Technique, Direct ; methods ; Humans ; Molecular Sequence Data ; Prevalence ; Rabies ; diagnosis ; epidemiology ; veterinary ; virology ; Rabies virus ; genetics ; immunology ; isolation & purification

Simple methods for measuring the levels of serum antibody against canine distemper virus (CDV) would assist in the effective vaccination of dogs. To develop an enzyme-linked immunosorbent assay (ELISA) specific for CDV, we expressed hydrophilic extra-viral domain (HEVD) protein of the A75/17-CDV H gene in a pET 28a plasmid-based Escherichia (E.) coli vector system. Expression was confirmed by dot and Western blotting. We proposed that detection of E. coli-expressed H protein might be conformation-dependent because intensities of the reactions observed with these two methods varied. The H gene HEVD protein was further purified and used as an antigen for an ELISA. Samples from dogs with undetectable to high anti-CDV antibody titers were analyzed using this HEVD-specific ELISA and a commercial CDV antibody detection kit (ImmunoComb). Levels of HEVD antigenicity measured with the assays and immunochromatography correlated. These data indicated that the HEDV protein may be used as antigen to develop techniques for detecting antibodies against CDV.
Animals ; Antigens, Viral/*diagnostic use ; Distemper/diagnosis/*virology ; Distemper Virus, Canine/*immunology ; Dog Diseases/*diagnosis/virology ; Dogs ; Enzyme-Linked Immunosorbent Assay/*veterinary ; Escherichia coli/genetics ; Genetic Vectors/genetics ; Hemagglutinins, Viral/*diagnostic use

Two non-radioactive probes using digoxigenin or biotin were developed for detecting canine herpesvirus (CHV) and compared for their sensitivities by in situ hybridization (ISH) in formalin fixed, paraffin embedded sections, which has been used routinely in veterinary fields. Sections of the CHV-infected cell preparation were subjected to several different ISH protocols using digoxigenin- or biotin-labeled probe respectively. Results were compared for the hybridization and background signal intensities. The best result was obtained by the optimized ISH protocol using digoxigenin-labeled probe for detection of CHV DNA. The optimized ISH assay, which developed in this study, may be a valid tool for the study of pathogenesis and diagnosis of CHV infection.
Animals ; Biotin/diagnostic use ; Cell Line ; DNA Probes/chemistry/genetics ; DNA, Viral/chemistry/genetics ; Digoxigenin/diagnostic use ; Dog Diseases/diagnosis/*virology ; Dogs ; Herpesviridae Infections/diagnosis/*veterinary/virology ; Herpesvirus 1, Canid/genetics/*isolation&purification ; In Situ Hybridization/methods/*veterinary ; Polymerase Chain Reaction/veterinary ; Sensitivity and Specificity