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

• Parasites, Hosts and Diseases
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• v.31 no.2
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• pp.141-148
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• 1993

ELISA-inhibition test using Paragonimus westermani specific monoclonal antibody (Mab) was investigated to improve the diagnostic specificity of paragonimiasis. By cell fusion, one hybridoma clone secreting un-n westemanl specific Mab was selected (Pwa-14), which reacted on bands of 28 kDa, 42.5 kDa, 89 kDa and 120.5 kDa. IFA showed Pwa-14 was located at the vitelline follicles. By micro-ELISA, 100% of 22 paragonimiasis cases were found positive, but 5 of 40 clonorchlasls cases (12.5%),3 of 26 cystlcercosis cases (7.7%) showed false positive. None of 10 sparganosis patients or 28 normal controls reacted positively. On the other hand, by ELISA-Inhibition test using a R westermcni specific Mab, 100% of patagonimlasls cases were found positive, and there were no positive in cysticercosis, sparganosis cases or normal controls, except 2 (5.0%) false-positive sera of 40 clonorchiasis cases. The ELISA-Inhlbltlon test using a Mab showed higher specificity in comparison with macro-ELISA for serodlgnosis of human paragonimlasis.

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

• Parasites, Hosts and Diseases
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• v.31 no.2
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• pp.149-156
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• 1993

Monoclonal antibodies (Mabs) were produced against crude scolex extract of T solium metacestodes, and applied to ELISA-inhibition test for improving the specificity of serodiagnosis of human cysticercosis. Four hybridomas secreting species-specific anti- cysticercal Mabs (Cya-1, Cya-7, Cya-28 and Cya-31) were selected. Each Mab reacted on antigenic components of 25.5 kDa (Cya-1), 28 kDa (rcya-7), 87.5 kDa (Cya-281), and 12.5 kDa (Cya-31). IFA showed that Cya-1 was located at the calcium corpuscles, and Cya-7 at the loose connective tissue of T soLium metacestode scolex. Cya-28 and Cya-31 reacted on the tegument of the scolex. By conventional ELISA, 23 out of 28 (82.1%) cysticercosis patients were found serologically positive, but 1 out of 9 (11.1%) sparganosls cases and 6 out of 31 (19.4%) paragonlmiasis cases showed false positives. By ELISA-Inhibition test using species-specific anti-cysticercal Mab Cya-7, 19 out of 28 (67.9%) cystlcercosis cases were found serologically positive, but there were no false positives In other parasitic infections.

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

• The Journal of the Korean Society for Microbiology
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• v.21 no.4
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• pp.473-480
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• 1986

Mumps is an extremly common infectious disease affecting predominantly young children hut it is not a severe disease in terms of mortality. One hundred and two sera from infants of 3 different groups which are vaccinated, unvaccinated and unknown were detected to mumps antibody. The tests used were Complement Fixation(CF) test, Single Radial Hemolysis(SRH) test, Hemagglutination Inhibition(HI) test, Enzyme Linked Immunosorbent Immunoglobulin G(ELISA IgG) test, Enzyme Linked Immunosorbent Immunoglobulin M(ELISA IgM) test. 1. The rate of positivity for mumps antibody in 102 sera wera 89.16%(74/83) by Hl test, 68.83%(53/77) by ELISA IgG test, 64.58%(62/96) by SRH test, 63.24%(43/68) by ELISA IgM test and 50.00%(49/98) by CF test. 2. The rate of positivity by 5 tests for 55 sera turned out to be very similar with above results respectively. 3. The correlation coefficients(r) between ELISA IgG test ant H1 test, ELISA IgG test and ELISA IgM test were 0.34(P<0.0l) and 0.31(P<0.02), respectively. 4. The percentage of apparently natural infection of mumps seemed to be 65.15%(43/66) in infants. 5. Seroconversion rate of mumps by vaccination were 90.91%(10/11). 6. Among the 53 infants who were tested with ELISA IgG 15 were below 15 months age of(28.30%) and this percentage may be taken as a suggestion that mumps vaccination should be given earlier than present practice. 7. ELISA IgG test was found very sensitive and recommendable method for large scale screening for the presence of antibody to mumps.

• Korean Journal of Veterinary Research
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• v.42 no.1
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• pp.73-80
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• 2002

An enzyme-linked immunosorbent assay (ELISA) using purified hemagglutinin of swine influenza virus (H1N1) as antigen was developed for detection of antibody to avian influenza virus (AIV). The sensitivity and specificity of a developed and commercial available ELISA kits were compared with those of agar gel precipitation (AGP) test and hemagglutination inhibition (HI) test using sera collected from chickens under condition of field exposure. The concentration of antigen, serum dilution and concentration of enzyme-conjugated secondary antibody in developed ELISA (S-ELISA) were 0.5ug/100ul, 1:200 and 0.03ug/100ul, respectively. The correlation coefficients between S-ELISA and commercial ELISA and HI titers were 0.419 and 0.533, respectively. A significant correlation (p < 0.01) was not found between HI and ELISA titers. The S-ELISA was found to be as more sensitive and specific than the AGP test, showing 86.8% sensitivity and 85.3% specificity. It is suggested that the ELISA using the SIV as antigen may be useful method as an investigating tool for AIV serological surveillance.

• Korean Journal of Veterinary Service
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• v.26 no.3
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• pp.215-219
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• 2003

This study was conducted to investigate the similarity between hemagglutination inhibition (HI) test and enzyme-linked immunosorbent assay(ELISA) titers and sample to positive ratio (S/P ratio) of Newcastle disease(ND) virus. To perform this study, the 372 sera of broiler chicks and 120 sera of layers and breed chicks were collected from slaughter house and farms, respectively. As a result of HI test out of different chicks, the positive percentage of ND antibody titer of broiler, layer and breeder, when a standard positive HI titer were '2', was 84.4%, 100% and 100%, respectively. The positive percentage of ND antibody titer by ELISA was shown 38.4%, 100% and 100% and S/P ratio were also shown 81.5%, 98.2% and 99.2%, respectively. The results of comparative survey with same sera by two experimental methods were as follows; In low HI titer, ELISA titer was not similar to HI titer, but S/P ratio was similar to it. In high HI titer, ELISA titer was not similar to HI titer. Therefore, HI titer was more similar to S/P ratio than ELISA titer.

• Korean Journal of Veterinary Research
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• v.46 no.3
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• pp.185-196
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• 2006

Newcastle disease (ND) is a highly contagious disease of poultry that can cause severe economic losses throughout the world. Vaccination has been used for a long time and proved as one of the most effective method to reduce the economic loss due to ND virus infection, The measurement of antibody titer such as hamagglutination-inhibition (Hl) test with sera has been used as a useful method to evaluate the immunity leve of host. However, Hl test is gradually being replaced by the enzyme linked-immunosorbent assay (ELISA), To evaluate the efficacy of ELISA in the chickens vaccinated with different procedure, present study has been performed. After SPF chicks and commercial broilers were vaccinated with different kinds of live vaccines such as V4, VG/GA and/or Bl at various time, the antibody level has been measured using both HI test and ELISA. Challenge test with velogenic viscerotropic NDV was also performed to measure the protective level of antibody. In the SPF chickens, the mean ELISA titer after vaccination and survival rate after challenge was increased and correlated with days post inoculation. More than 80% of chickens with higher than 1,000 ELISA titer after vaccination were survived after challenge with velogenic ND virus and had good correlation between survival rate and antibody titier. In commercial broiler chickens, most of them at market age had low level of ELISA titer regardless of the number of vaccination, and had a low correlation between survival rate and ELISA titer. However, the ELISA titer of remaining birds after challenge was increased. This result indicated that ELISA titer had good response against velogenic NOV infection compared to Hl titer.

• Parasites, Hosts and Diseases
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• v.29 no.3
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• pp.293-310
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• 1991

Clonorchis sinensis is a common parasite of man in Korea. Researches on the specific antigens of C. sinensis would be valuable not only because those elucidate the molecular characteristics of this fluke but also because it is applicable to immunodiagnosis. Although many monoclonal antibodies have been used in the field of parasite immunology, few articles on monoclonal antibodies against C. sinensis have been published so far. The aim of this study was to analyse C. sinensis antigens recognized by monoclonal antibodies, and to set up ELISA-inhibition test using C. sinensis specific monoclonal antibodies for improved specificity of immunodiagnostic tests. By fusion between spleen cells of the mice immunized with C. sinensis water-soluble crude adult worm antigens and plasmacytoma cells of mouse origin, 29 hybridoma clones secreting anti-C. sinensis monoclonal antibodies were made, and 8 clones among those were found specific. After cell cloning, isotypes of 6 selected specific monoclonal anti- bodies were determined to be IgGl, IgG2b and IgA. Four exposed antigenic determinants of natural infection were recognized by different specific monoclonal antibodies. By enzyme-immunoelectrotransfer blot, 10 KD, 34 KD antigenic determinants were found to be reacted with CsHyb 0714-20, CsHyb 0605-10 monoclonal antibodies, respectively, The antigenic determinant recognized by CsHyb 0714-20 monoclonal antibody was revealed to be located at the surface and parenchyme of a parasite by indirect immunoauorescent antibody technique, and those reacted with CsHyb 0605-10, CsHyb 0714-25 monoclonal antibodies were found at the parenchyme and intestine. The antigenic determinant reacted with CsHyb 0605-23 monoclonal antibody was found mainly around the uterine eggs. Four antigenic determinants recognized by specific monoclonal antibodies were all found to be present in the early eluted fractions of C. sinensis antigens separated by Sephadex G-200 gel filtration. By conventional ELISA, 75% of clonorchiasis cases were found positive, but 7.1% of normal controls and 37.5% of paragonimiasis cases showed false positives. However, by ELISA-inhibition test using C. sinensis specific monoclonal antibody (CsHyb 0605-23), 77.1% of clonorchiasis cases were found positive, and there were no false positives in normal controls or paragonimiasis cases, indicating 100% specificity. The ELISA- inhibition test using monoclonal antibodies was found to have same sensitivity and definitely high specificity in comparison with conventional ELISA for serodiagnosis of human clonorchiasis.