• Food Science of Animal Resources
• /
• v.20 no.3
• /
• pp.231-235
• /
• 2000

원유에 존재하는 Ps. fluorescens의 균수를 신속하게 측정하기 위한 Inhibition Enzyme Linked Immunosorbant Assay (ELSIA)를 개발하기 위해 Ps, fluorescens(KCTC 2344)을 산란계에 접종하여 Ps.fluorescens에 대한 anti-Ps. fluorescens IgY 항체를 생산하고 그 항체의 역기를 ELISA로 측정한 결과 32일까지 항체 역가가 증가하였으며, 분리된 IgY 항체의 titer는 1:128,000으로 나타났다. Anti-Ps.fluorescens IgY 항체에대한 교차반응을 조사한 결과 그람양성균 Lactococcus faecalis, Staphylococcus aureus 뿐만 아니라 그람음성 균인 Achrombacter sal-monisida, Escherichia coil와도 교차반응을 거의 하지 않는 것으로 나타났다. Anti-Ps. fluo-rescens IgY 항체를 가지고 Inhibition ELISA 방법으로 Ps. fluorescens 균수를 신속한 측정할 수 있는 표준곡선을 작성한 결과 Ps. fluorescens균을 5.0$\times$$10^4$cfu/ml부터 5.0$\times$$10^{8}$cfu/ml 측정할 수 있는 것으로 나타났다.

• Biomedical Science Letters
• /
• v.2 no.1
• /
• pp.121-126
• /
• 1996

Specific monoclonal antibodies(mAbs) against bis-indole alkaloids related to vinblastine were established to develop a simple and specific immunoassay system for the quantitation of Vinca alkaloids. Vinca alkaloids were extracted from tissue cultured cells of periwinkle plant (Vinca rosea L.). Spleen cells from Balb/c mice immunized with vinblastine-bovine serum albumin(VBL-BSA) conjugate as immunogen were fused with myeloma cells(Sp2/0-Ag.14) in the presence of polyethylene glycol. In the preliminary experiments, 32 clones which highly reacted with VBL-BSA conjugate were selected by ELISA(Enzyme-linked immunosorbent assay).These clones were further analyzed by inhibition assay of ELISA. The results obtained with two typical monoclonal antibodies, KN-1 and KN-2, were described. KN-1 exhibited considerable reactivities with soluble dimeric bis-indole alkaloids, whereas no cross reacted with monomeric bis-indole alkaloids. However KN-2 showed cross reactivity with mono- and di-meric bis-indole alkaloids. Furthermore, KN-1 was applied to the immunoassay system for determining the VBL amounts of in vitro cultured cell extracts. This assay system could detect dimeric vinca alkaloid as low as 0.05 nM.

• Journal of Food Hygiene and Safety
• /
• v.11 no.4
• /
• pp.287-290
• /
• 1996

To control the maximum residue level (MRL) for sulfamethazine (SMZ) residues in pork tissue, a microbial inhibition method is a regulatory screening assay method in Korea. Microwell plate-based competitive enzyme immunoassay (ELISA) kit is avalable for routine screening of SMZ residues in pork tissue. One ELISA kit is evaluated. Phosphate buffer extracts of samples fortified with SMZ at 0, 1, 5, and 10 ng/g were used in a recovery test of the kit. Market pork samples were assayed by the kit. Recovery of sulfamethazine was 104% at 10 ng/g. Intraassay variations and interassay variations for the kit were 7.70% and 5.76%, respectively. Concentration causing 50% inhibition of color development compared with blanks was 16.4ng. The violative pork samples with over MRL (0.1 $\mu\textrm{g}$/g) was 4 of 32 cases (12.5%) by used ELISA kit. This result indicates a possibility of the ELISA kit for screening test of SMZ residues in pork tissue, and still needs a comfirmatory assay for mandatory purposes.

• Archives of Pharmacal Research
• /
• v.10 no.1
• /
• pp.18-24
• /
• 1987

Mouse monocolonal antibodies to Hepatitis B surface antien (HBsAg) were prepared and their functional capabilities tested by the method of solid phase enzyme linked immuno sorbent assay (ELISA). HBsAg binding studies inicated that one monoclonal antibody 6E-1-1 bound more HBsAg at a faster rate than the other monoclonal antibodies. Also, for the binding inhibition studies with the selected monoclonal antibody 6E-1-1, one monoclonal antibody 8D-3-6 didn't exhibit binding inhibition for HBsAg. Then, a simultaneous ELISA method was developed for the immunodiagnosis of HBsAg. Different combinations of two monoclonal antibodies as solid phase and horseradish peroxidase (HRPO) labeled phase were studied. The combination of monoclonal antibody of higher affinity constant (6E-1-1) immobilized in a solid phase and monoclonal antibody of lower affinity constant (8D-3-6) as a HRPO laeled phase was more sensitive when two monoclonal antibodies of different affinity constants for HBsAg were prepared.

• Korean Journal of Veterinary Service
• /
• v.27 no.1
• /
• pp.81-87
• /
• 2004

This study was conducted to investigate the similarity between hemagglutination inhibition (HI) test and enzyme-linked immunosorbent assay(ELISA), the HI titer and mean ratio S/P ratio) of avian influenza virus. To perform this study, the 1,457 sera of layers 21 farms in May, July and September, respectively. As a result of HI test, positive rates were 480 to 422 (92.1%) in May, 494 to 394(79.8%) in July and 483 to 402(83.2%) in September, and the mean antibody titer were 4.6, 4.3, 4.0 to 0.3 decreased, respectively. The positive rates by ELISA, 480 to 475(99.0%) in May, 494 to 485(98.2%) in July, 483 to 472(97.7%) in September, and the mean S/P ratio were 2.319, 2.557 and 2.380, respectively. The result of HI test and ELISA positive 480 to 422(92.1%), 475(99.0%), 494 to 394(79.8%), 485(98.2%) and 483 to 402(83.2%), 472(97.7%). Therefore, ELISA was shown more sensitive compare the HI titers.

• Journal of fish pathology
• /
• v.9 no.2
• /
• pp.169-176
• /
• 1996

An indirect double antibody enzyme-linked immunosorbent assay (ELISA) was developed for rapid detection of a new virus isolated from abnormally swimming salmonid fish, RVS (Retrovirus of salmonid). Results using brain tissue homogenates, and infected cell cultures are described. The sensitivity of the methods is $10^{2.6}$ $TCID_{50}/100{\mu}l$ of the examined cell culture fluid. The specificity was confirmed by the ELISA inhibition test and virological examinations. Viral antigen could be detected in artificially infected fish tissue homogenates. The assay will allow the diagnosis of RVS-infected fish within a day.

• Archives of Pharmacal Research
• /
• v.21 no.3
• /
• pp.253-259
• /
• 1998

In this study, we developed immunoassay methods for the more convenient and effective detection of rat tracheal mucin and the results were compared with those of [$3^H$]glucosamine based gel-filtratioh method. A monoclonal anti-rat tracheal mucin antibody, mAbRT03, which specifically recognizes rat tracheal mucins, was used throughout in this study. To induce mucin secretion, varying concentrations of ATP (0-2 mM) were applied to the primary rat tracheal surface epithelial (RTSE) cell culture which had been metabolically radiolabeled with [$3^H$]glucosamine and the secretion of mucin was analyzed both by the immunoassay and the gel-filtration chromatography methods. For the immunoassay, the following two procedures were employed. 1) Simple ELISA; the culture spent media were directly coated onto the assay plate and the immunoreactivity with mAbRT03 was assessed from the standard curve generated with the purified rat mucin. 2) Inhibition ELISA; A known amount of the purified rat mucin was coated onto the assay plate and then ATP-stimulated culture spent media were added to inhibit the immunorelitivity with mAbRT03. The contents of mucin in the sample were calculated from the standard inhibition curve which was generated with the purified rat mucin. The assay results obtained from the immunoassays were identical with those from the gel-filtration methods. The present result indicates that ELISA can be substituted for the laborious, time-consuming gel-filtration assay in studying the regulation of airway mucin release from cultured airway epithelial cells.

• Korean Journal of Veterinary Research
• /
• v.56 no.3
• /
• pp.189-192
• /
• 2016

The virus neutralization (VN) test was used to determine potency of the infectious bronchitis (IB) vaccine. The results of VN, hemagglutination inhibition (HI), and enzyme-linked immunosorbent assay (ELISA) were compared with those of the IBV M41. The $r^2$ values between VN and HI titers and the ELISA antibody titer were 0.8782 and 0.0336, respectively, indicating a high correlation between VN and HI, but not VN and ELISA. The Cohen's kappa coefficient between the VN titer of 2 $log_{10}$ and HI titer of 5 $log_2$ was 0.909. Our results showed that VN could be replaced with HI for testing the potency of IBV M41.

• BMB Reports
• /
• v.30 no.5
• /
• pp.326-331
• /
• 1997

To construct a competitive ELISA standard curve for the detection of glucose-6-phosphate debydrogenase (G6PD), we used highly purified native G6PD (nG6PD) as both immobilized and soluble antigens and anti-G6PD serum raised against nG6PD as antibody. The polystyrene cuvettes coated with nG6PD were challenged with a mixture of a limiting amount of anti-G6PD serum and various doses of nG6PD as competitors followed by incubation with alkaline phosphatase-anti-IgG conjugate. The competitive ELISA did not exhibit the typical sigmoidal dose-response curve characteristic of competition immunoassays under the optimal concentrations of antigen and antibody. The soluble nG6PD used as competitor failed to effectively inhibit the binding of antibodies to the immobilized nG6PD. The addition of NADP, a cofactor of G6PD enzyme, to coating buffer used for immobilizing nG6PD to the cuvettes and PBS-Tween-BSA buffer for diluting competitors did not improve the inhibition of antibody binding to immobilized nG6PD by soluble n/G6PD. The addition of BSA to coating buffer did not increase inhibition, either. Surprisingly, when partially active G6PD (paG6PD), obtained by repeated freeze-thawing, was used as competitor, the antibody binding to either immobilized nG6PD or immobilized paG6PD was inhibited 49-58%. We conclude that an effective competitive ELISA system with nG6PD enzyme and anti-G6PD serum for the detection of G6PD may not be established due to the poor inhibition of antibody binding to immobilized nG6PD by soluble nG6PD under the present assay conditions and that the inhibition may be improved by using an inactivated enzyme as competitor regardless of the type of immobilized antigen used. These results imply that the immobilized nG6PD may undergo denaturation upon binding to the polystyrene cuvettes and that our anti-G6PD serum may recognize denatured enzyme better than active enzyme.

• Journal of Food Hygiene and Safety
• /
• v.10 no.4
• /
• pp.213-217
• /
• 1995

A screening method has been developed for detecting sulfamethazine(SMZ) contamination of meat or feeds by using horseradish peroxidase (HRP) labeled protein A (Prot AHRP)and an indirect competitve enzyme-linked immunosorbent assay(ELISA). The assay is based on competitve binding of guinea pig anti-SMZ with SMZ in smaple and SMZ-gelatin conjugate(SMZ.GEL). Percent binding (B.Bo$\times$100) was calculated from the absorbance in the absence (B0) and presence (B) of SMZ. By the sandard curve prepared by plotting log(SMZ) vs percent binding of each known reference solution, the detection limit was 1.0ppb or less. Cross reacton with sulfadimethoxine, sulfaguaniding, sulfamerazine, sulfamthoxpyridazine, sulfanilamide, sulfisomidine and sufisoxazole were not observed. But sulfamerazine crossreacted in the test. The EC-50 value (concentration causing 50% inhibition of color development compared with blank) of sulfamerazine was 2.0 ppm. Further quality control will make the ELISA system ideal for the detection of SMZ in meat or feeds.