Evaluation of enzyme-linked immunosorbent assay (ELISA) and immunofluorescent antibody (IFA) test for the detection of porcine reproductive and respiratory syndrome virus (PRRSV) antibody in pigs from conventional farms   总被引：1，自引：0，他引：1  

Yahara Y  Ohkubo Y  Kariwa H  Takashima I 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(7):583-588

To evaluate the immunofluorescent antibody (IFA) test and enzyme-linked immunosorbent assay (ELISA) for detecting the porcine reproductive and respiratory syndrome virus (PRRSV) antibody, conventional pigs in PRRSV-positive and -negative commercial farms were examined. Antibody development patterns in ELISA and IFA tests were compared in 3 week old piglets experimentally infected with the PRRSV. The virus was detected from 2 days post infection (PI) and then the antibody titers and S/P ratios rose by both methods. A total of 208 serum samples were collected from 4 PRRSV-negative farms and 210 samples from PRRSV-positive farms, and were tested for the PRRSV antibody by IFA and ELISA. The titer of 64 should be set as the cut-off point in IFA for field sera. Similarly, the cut-off S/P ratio should be set at 0.4 in ELISA. A high degree of correlation was observed between antibody titers by the two methods in these 418 samples, with a correlation coefficient of 0.84. The coincidence rate between the two tests was 84.7% (354/418). In non-coincident cases, ELISA was able to detect the antibody with a low titer in the serum samples which were negative in IFA but from PRRSV positive farms. ELISA was more sensitive than IFA to detect PRRSV infected animals or farms.  相似文献   

Early cytokine response of gnotobiotic piglets to Salmonella enterica serotype typhimurium     

Splíchal I  Trebichavský I  Muneta Y  Mori Y 《Veterinary research》2002,33(3):291-297

Cytokine response against Salmonella Typhimurium is traditionally studied in conventional animals. Germ-free animals, however, enable to study response against infection without background effect of other microorganisms. Plasma and ileal inflammatory cytokines in germ-free piglets orally infected with virulent LT2 strain or, with a non-virulent SF1591 rough mutant were quantified by ELISA. In plasma and ileal washes, IFN-gamma levels significantly increased in both infected groups. TNF-alpha and IL-18 were mostly missing in plasma 24 h after infection. In the ileum, IFN-gamma, TNF-alpha, and IL-1beta were induced mainly by the virulent strain, whereas IL-18 was induced in highest quantity by non-virulent Salmonella. These data confirmed an important role of IFN-gamma, as well as other inflammatory cytokines in early stage of salmonellosis.  相似文献   

Rapid detection of chitosanase activity in chitosanase gene-transformed strains of <Emphasis Type="Italic">Enterobacter cloacae</Emphasis> by lytic infection of specific bacteriophages     

Yoshihiro Takikawa  Yuuki Ishii  Keiichi Fujiwara  Yoshinori Matsuda  Teruo Nonomura  Koji Kakutani  Yukio Tosa  Shigeyuki Mayama  Hideyoshi Toyoda 《Journal of General Plant Pathology》2003,69(2):131-137

 In combination with lytic infection by virulent phages, a simple method for monitoring transgenic strains of Enterobacter cloacae was developed in this study. First, 15 strains of E. cloacae were used as indicator bacteria to isolate virulent phages with different host ranges. Of the phages isolated, five isolates (EcP-22, -35, -45, -55, and -70) were used to construct a set of virulent phages corresponding to all strains of E. cloacae. Using this phage set, a rhizosphere strain (KRM-055E) of E. cloacae was effectively screened from field soil. KRM-055E was transformed with a prokaryotic chitosanase gene csnSM1 and infected with the phage EcP-03, which can lyse the strain most effectively. The lysis of KRM-055E/csn occurred 2 h after inoculation, and the chitosanase activity was simply detected by dropping the lysate onto an agar plate containing glycol chitosan. The positive signal for chitosanase activity was detected in the 2-h lysates, and the signal intensity reached a maximum in the 5-h lysate. The present assay was simple, rapid, inexpensive, easy to perform, and applicable to another strains. Received: August 2, 2002 / Accepted: October 31, 2002 Acknowledgments This work was supported in part by a grant (no. 99L01205) from the “Research for the Future” program of the Japan Society for the Promotion of Science. We are grateful to Dr. M. Sato, National Institute of Agrobiological Science, Dr. H. Okamoto, Fukui Agricultural Experiment Station, and Dr. K. Tsuda, Kyoto Prefectural Institute of Agricultural Biotechnology, for kindly providing E. cloacae strains. We thank Dr. P. Park, Kobe University, for technical support with the electron microscopic observations.  相似文献   

Infection behavior of Alternaria alternata Japanese pear pathotype and localization of 1,3- β -d -glucan in compatible and incompatible interactions between the pathogen and host plants     

Tomoko Suzuki  Takeshi Shinogi  Yoshihiro Narusaka  Pyoyun Park 《Journal of General Plant Pathology》2003,69(2):91-100

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Partial Purification of Thai Isolate of Citrus Huanglongbing (Greening) Bacterium and Antiserum Production for Serological Diagnosis     

Yoshihiro OHTSU  Maitree PROMMINTARA  Seiichi OKUDA  Tomoaki GOTO  Takeshi KANO  Kazuo NAKASHIMA  Meisaku KOIZUMI  Jun IMADA  Koji KAWASHIMA 《Journal of General Plant Pathology》2002,68(4):372-377

We aimed to improve the purification of citrus Huanglongbing (greening) bacterium (HB), Candidatus Liberobacter asiaticum and to produce an antiserum against HB. Periwinkle plants Catharantus roseum L. graft-inoculated with HB were used to produce an antiserum. All young leaves of new shoots incubated at 20–25°C and 25–30°C, a few mature leaves incubated at 20–25°C, and all mature leaves incubated first at 25–30°C and later transferred to 20–25°C developed yellowing symptoms and were then used to prepare immunogen. The HB was partially purified from these leaves by an improved method that included a macerating enzyme treatment of the midribs of infected leaves and homogenization of infected phloem sieve tissues. An antiserum raised against partially purified HB reacted clearly at a dilution of 1/16 with HB-infected citrus extract prepared at a concentration of 40 times, but did not react with healthy or tristeza virus-infected citrus extract in microprecipitin tests. Received 23 August 2002/ Accepted in revised form 4 December 2002  相似文献   

Reduction of Spore Density of Plasmodiophora brassicae in Soil by Decoy Plants     

Hiroharu MURAKAMI  Seiya TSUSHIMA  Takayuki AKIMOTO  Yoshihiro SHISHIDO 《Journal of General Plant Pathology》2001,67(1):85-88

The severity of clubroot (Plasmodiophora brassicae) on Chinese cabbage was reduced by growing plants such as oats, spinach and leafy daikon prior to Chinese cabbage in pot experiments. Resting spore densities of P. brassicae in the soil were 29–62%, depending on the pervious crop, as compared to unplanted control plot after ploughing under the previously cultivated plants. Root hairs of the preceding plants were infected with P. brassicae, but clubbed roots were not formed on these plants. The results indicate that these plants functioned as decoy plants reducing the resting-spore density in soil and thereby suppressing disease severity. Received 21 February 2000/ Accepted in revised form 5 September 2000  相似文献   

Characterization and epitope mapping of monoclonal antibodies to the nucleocapsid protein of severe acute respiratory syndrome coronavirus     

Kariwa H  Noda H  Nakauchi M  Ishizuka M  Hashiguchi K  Hashimoto S  Yoshii K  Asano A  Agui T  Kogaki H  Kurano Y  Uchida Y  Fujii N  Okada M  Takashima I 《The Japanese journal of veterinary research》2008,55(4):115-127

The sudden emergence of severe acute respiratory syndrome (SARS) at the end of 2002 resulted in 774 reported deaths from more than 8000 cases worldwide. As no effective vaccines or antiviral agents are available, the most effective measure to prevent the expansion of a SARS epidemic is the rapid diagnosis and isolation of SARS patients. To establish specific diagnostic methods, we generated nine clones of monoclonal antibodies to nucleocapsid protein (NP) of SARS-coronavirus (SARS-CoV). On immunofluorescent antibody assay and Western blotting analysis, none of the monoclonal antibodies showed cross-reactivity to authentic and recombinant NPs of human coronavirus (HCoV) 229E strain. To determine the region on the NP molecule where the monoclonal antibodies bind, we generated four truncated recombinant NPs and analyzed the reactivity between monoclonal antibodies and truncated NPs. Two monoclonal antibodies reacted with a truncated NP covering from amino acid residues 111 to 230, and seven reacted with another truncated NP covering from amino acid residues 221 to 340. Epitope mapping analysis indicated that monoclonal antibody SN5-25 recognized the amino acid sequence Q(245)TVTKK(250) On SARS-NP. Within the epitope, Q245, T246, V247, K249, and K250 appeared to form an essential motif for monoclonal antibody SN5-25 to bind. The information about binding sites and epitopes of monoclonal antibodies may be useful for the development of new diagnostic methods for SARS and for analyzing the function of N protein of SARS-CoV.  相似文献   

Expression of inflammatory-related factors in porcine anterior pituitary-derived cell line   总被引：2，自引：0，他引：2  

Nagai Y  Ogasawara H  Taketa Y  Aso H  Kanaya T  Miyake M  Watanabe K  Ohwada S  Muneta Y  Yamaguchi T 《Veterinary immunology and immunopathology》2008,124(3-4):201-208

Recent studies have shown that undifferentiated stem cells act as immunomodulators. To investigate the immunomodulatory function of the progenitor cells of the anterior pituitary gland, we attempted to establish a stem/progenitor cell line from the porcine anterior pituitary gland, and to detail its inflammatory cytokine expression. A cloned cell line from the porcine anterior pituitary gland was established and was designated as the porcine anterior pituitary-derived cell line (PAPC). PAPC expressed the mRNA of Nanog and Oct-4, and showed positive immunoreactivity for beta-catenin and Hes1 in its nucleus. PAPC grew stably by repeated passage and rapidly in the EGF and bFGF containing medium. RT-PCR showed that PAPC expressed mRNA of IL-1alpha, IL-6, IL-12, IL-15, IL-18 and TLR4. PAPC expressed S100alpha and IL-18 protein, which was localized in the marginal epithelial cells of Rathke's pouch. These results suggest that PAPC is a stem/progenitor cell and may regulate anterior pituitary cell function through an immuno-endocrine pathway.  相似文献   

Immune response of gnotobiotic piglets against Mycoplasma hyopneumoniae     

Muneta Y  Minagawa Y  Shimoji Y  Ogawa Y  Hikono H  Mori Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(10):1065-1070

In this study, several cytokine responses were investigated during Mycoplasma hyopneumoniae (Mhp) infection using a gnotobiotic infection model. We found that several inflammatory cytokines (IL-1beta, IL-8, IL-18, and TNF-alpha) and an anti-inflammatory cytokine IL-10 were induced from peripheral blood mononuclear cells (PBMC) of germ-free (GF) piglets stimulated with heat killed Mhp whole antigens, but no IFN-gamma and IL-4 were induced by Mhp. After the intranasal infection of Mhp, IL-1beta, IL-8, IL-18, and IFN-gamma were also detected in the broncho-alveolar lavage fluids (BALF). The antigen-specific IFN-gamma and IL-10 responses after infection of Mhp were gradually suppressed during Mhp infection as well as non-specific immune response to concanavalin A (ConA) and lipopolysacchalide (LPS) at early stage of infection. These results suggested that Mhp infection modulates the immune response of pigs by inducing several cytokines, and causes immuno-suppression of pigs in a gnotobiotic condition.  相似文献   

Immunohistochemical distribution of viral antigens in pigs naturally infected with porcine teschovirus   总被引：3，自引：0，他引：3  

Yamada M  Kozakura R  Kaku Y  Nakamura K  Yamamoto Y  Yoshii M  Miyazaki A  Tsunemitsu H  Narita M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(3):305-308

A distribution of porcine teschovirus (PTV) antigens in pigs naturally infected with PTV is presented using the method of immunohistochemical examination. In the nervous system, PTV antigens were found in the cytoplasm of neuronal cells and glial cells distributed in the spinal ventral horn and brain stem, and also in the cytoplasm of ganglion cells in the spinal ganglion. No antigens were seen in the cerebral hemisphere. In the nervous system, the distribution of PTV antigens was consistent with lesions characteristic of nonsuppurative encephalomyelitis. In the other examined organ, PTV antigens were observed in bronchiolar epithelial cells in the lung, hepatocytes in the liver, epithelial cells in the tonsils and the myenteric nerve plexus in the small and large intestine.  相似文献