Résumé
Pepino mosaic virus (PepMV) causes severe disease in tomato and other Solanaceous crops around globe. To effectively study and manage this viral disease, researchers need new, sensitive, and high-throughput approaches for viral detection. In this study, we purified PepMV particles from the infected Nicotiana benthamiana plants and used virions to immunize BALB/c mice to prepare hybridomas secreting anti-PepMV monoclonal antibodies (mAbs). A panel of highly specific and sensitive murine mAbs (15B2, 8H6, 23D11, 20D9, 3A6, and 8E3) could be produced through cell fusion, antibody selection, and cell cloning. Using the mAbs as the detection antibodies, we established double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), Dot-ELISA, and Tissue print-ELISA for detecting PepMV infection in tomato plants. Resulting data on sensitivity analysis assays showed that both DAS-ELISA and Dot-ELISA can efficiently monitor the virus in PepMV-infected tissue crude extracts when diluted at 1:1 310 720 and 1:20 480 (weight/volume ratio (w/v), g/mL), respectively. Among the three methods developed, the Tissue print-ELISA was found to be the most practical detection technique. Survey results from field samples by the established serological approaches were verified by reverse transcription polymerase chain reaction (RT-PCR) and DNA sequencing, demonstrating all three serological methods are reliable and effective for monitoring PepMV. Anti-PepMV mAbs and the newly developed DAS-ELISA, Dot-ELISA, and Tissue print-ELISA can benefit PepMV detection and field epidemiological study, and management of this viral disease, which is already widespread in tomato plants in Yunnan Province of China.
Sujets)
Animaux , Femelle , Souris , Anticorps monoclonaux/immunologie , Chine , Clonage moléculaire , Test ELISA/méthodes , Hybridomes , Solanum lycopersicum/virologie , Souris de lignée BALB C , Maladies des plantes/virologie , Potexvirus/métabolisme , Sensibilité et spécificité , NicotianaRésumé
Rice stripe virus (RSV) causes dramatic losses in rice production worldwide. In this study, two monoclonal antibodies (MAbs) 16E6 and 11C1 against RSV and a colloidal gold-based immunochromatographic strip were developed for specific, sensitive, and rapid detection of RSV in rice plant and planthopper samples. The MAb 16E6 was conjugated with colloidal gold and the MAb 11C1 was coated on the test line of the nitrocellulose membrane of the test strip. The specificity of the test strip was confirmed by a positive reaction to RSV-infected rice plants and small brown planthopper (SBPH), and negative reactions to five other rice viruses, healthy rice plants, four other vectors of five rice viruses, and non-viruliferous SBPH. Sensitivity analyses showed that the test strip could detect the virus in RSV-infected rice plant tissue crude extracts diluted to 1:20 480 (w/v, g/mL), and in individual viruliferous SBPH homogenate diluted to 1:2560 (individual SPBH/μL). The validity of the developed strip was further confirmed by tests using field-collected rice and SBPH samples. This newly developed test strip is a low-cost, fast, and easy-to-use tool for on-site detection of RSV infection during field epidemiological studies and paddy field surveys, and thus can benefit decision-making for RSV management in the field.
Sujets)
Anticorps monoclonaux/composition chimique , Chine , Chromatographie d'affinité/méthodes , Collodion/composition chimique , Colloïdes/composition chimique , Or colloïdal/composition chimique , Test de matériaux , Membrane artificielle , Oryza/virologie , Maladies des plantes/virologie , Reproductibilité des résultats , Sensibilité et spécificité , Spécificité d'espèce , Tenuivirus/isolement et purificationRésumé
<p><b>OBJECTIVE</b>To investigate the effects of Shexiang Baoxin Pill (SBP) on function of endothelial progenitor cells (EPCs) and its nitric oxide (NO) secretion.</p><p><b>METHODS</b>Total mononuclear cells were isolated from human peripheral blood by ficoll density gradient centrifugation and inoculated on the human fibro-ligandin encrusting plate. After 7 days of in vitro culture, adherent cells were collected and incubated with SBP for 24 h. The proliferation, migration, adhesive activity, vasculogenesis capacity and NO secretion of EPCs were assayed using MTT, Transwell chamber, adhesion determination, in vitro vasculogenesis kit and nitrate reductase method, respectively.</p><p><b>RESULTS</b>EPCs incubated with SBP showed the capacities higher than those of control in proliferation, migration, adhesion, in vitro vasculogenesis, and with a higher NO concentration in the culture supernatant.</p><p><b>CONCLUSION</b>SBP can improve the function of EPCs, which might be a novel mechanism of its effects in improving vascular endothelial function and promoting angiogenesis.</p>
Sujets)
Humains , Différenciation cellulaire , Physiologie , Mouvement cellulaire , Prolifération cellulaire , Cellules cultivées , Médicaments issus de plantes chinoises , Pharmacologie , Cellules endothéliales , Biologie cellulaire , Métabolisme , Physiologie , Agranulocytes , Biologie cellulaire , Monoxyde d'azote , Cellules souches , Biologie cellulaire , Métabolisme , PhysiologieRésumé
<p><b>OBJECTIVE</b>To study the effects of palmitic acid (PA) on the proliferation of peripheral blood-derived endothelial progenitor cells (EPCs) in vitro.</p><p><b>METHODS</b>The mononuclear cells (MNCs) were isolated from the peripheral blood by Ficoll density-gradient centrifugation. The isolated EPCs were characterized by Di-LDI uptake and FITC-lectin binding assay using laser confocal microscope, and further identified by detection of CD34, CD133 and VEGFR2 expression using flow cytometry. The cultured EPCs were incubated in the presence of PA at the concentrations of 0, 50, 100, 200, 400 and 800 micromol/L for different durations (0, 12, 24, 36, 48 and 60 h). The cell morphology was observed and cell proliferation determined with CCK-8 assay.</p><p><b>RESULTS</b>Incubation with 400 and 800 micromol/L of PA significantly inhibited the proliferative ability of EPCs as compared with the control group (P < 0.05). PA at 400 micromol/L had the strongest effect on the cell proliferation, and this effect was intensified with the passage of time, reaching the peak at 48 h with the growth inhibition rate of 58.59% (P < 0.05).</p><p><b>CONCLUSION</b>High-concentration PA can significantly inhibit the proliferation of EPCs in vitro.</p>