• Journal of Preventive Medicine and Public Health
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• v.18 no.1
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• pp.51-57
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• 1985

To attempt to measure the effect of domestic product P.H.A. kit 'Hepa-S' after completion of 'Hepa-Vax' vaccination schedule, P.H.A. test and R.I.A. test on the 330 healthy adults were carried out. The results obtained were as follow ; 1. The positive anti HBs rate after completion of 'Hepa-Vax' vaccination were; in P.H.A. test with domestic product P.H.A. kit 81.2%, in P.H.A. test with foreign product P.H.A. kit 82.7%, and in R.I.A. test 95.8% 2. Using the result of R.I.A. test as the standard, sensitivity of P.H.A. test with domestic product P.H.A. kit was 84.8% and specificity was 100.0% 3. Using the result of R.I.A. test as standard, sensitivity of P.H.A. test with foreign P.H.A. kit was 86.4% and specificity was 100.0%. 4. The concordance rate of P.H.A. test with domestic product and foreign product kit was 98.5%. On the result of this study, there was no significant difference in the validity between the domestic product P.H.A. kit 'Hepa-S' and the foreign P.H.A. kit $'Hebsgencell^{TM}'$. So that it is recommendable to use domestic product P.H.A. kit instead of foreign product P.H.A. kit.

• Parasites, Hosts and Diseases
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• v.31 no.1
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• pp.49-56
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• 1993

Specific antibody test in serum and cerebrosinal fluid (CSF) is still the main mode of serological diagnosis of cystiercosis. Of different techniques of artibody test, enzyme-linked immunosorbent assay (micro-ELISA) has widely been applied. This study was undertaken to observe whether diagnostic capability can be Improved by applying more sensitive techniques such as Protein A-ELISA and avidin biotin complex ELISA (ABC-ELISA). When evaluated using 115 sera of human cysticercosis, the antibody positive rates were not significantly improved in Protein A-ELISA (82.6%) and in ABC-ELISA (86.1%) than in micro-ELISA (81.7%). The specificities, evaluated in 165 sera from other diseases and normal controls, were significantly improved (88.5% by micro-ELISA, 93.3% by Protein A-ELISA and 93.8% by ABC-ELISA). Antibody levels (absorbance, abs.) in individual serum were correlated well (r : 0.83∼0.86) each other. An actual benefit of Protein A-ELISA and ABC-ELISA was that they needed smaller amount of test sample.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.1-7
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• 2014

Plasmodium vivax reemerged in the Republic of Korea (ROK) in 1993, and is likely to continue to affect public health. The purpose of this study was to measure levels of anti-P. vivax antibodies using indirect fluorescent antibody test (IFAT) in border areas of ROK, to determine the seroprevalence of malaria (2003-2005) and to plan effective control strategies. Blood samples of the inhabitants in Gimpo-si, Paju-si, and Yeoncheon-gun (Gyeonggi-do), and Cheorwon-gun (Gangwon-do) were collected and kept in Korea Centers for Disease Control and Prevention (KCDC). Out of a total of 1,774 serum samples tested, the overall seropositivity was 0.94% (n=17). The seropositivity was the highest in Paju-si (1.9%, 7/372), followed by Gimpo-si (1.4%, 6/425), Yeoncheon-gun (0.67%, 3/451), and Cheorwon-gun (0.19%, 1/526). The annual parasite incidence (API) in these areas gradually decreased from 2003 to 2005 (1.69, 1.09, and 0.80 in 2003, 2004, and 2005, respectively). The highest API was found in Yeoncheon-gun, followed by Cheorwon-gun, Paju-si, and Gimpo-si. The API ranking in these areas did not change over the 3 years. The seropositivity of Gimpo-si showed a strong linear relationship with the API of 2005 (r=0.9983, P=0.036). Seropositivity data obtained using IFAT may be useful for understanding malaria prevalence of relevant years, predicting future transmission of malaria, and for establishing and evaluating malaria control programs in affected areas.

• Korean journal of applied entomology
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• v.14 no.4 s.25
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• pp.193-198
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• 1975

This experiment was performed to clarify the concentration of rice stripe virus in the rice Plant leaves by serological test, and was attempted to inspect the virus carrier among small brown planthopper by antibody-sensitized hemagglutination test. The antiserum was prepared by injecting intervenously into the external marginal vein of the ear of a rabbit. The precipitin titer of it was 1 : 16. The rough virus fluid prepared from diseased leaves was centrifuged at 10.000 rpm, and then the supernatant solution was treated at $55^{\circ}C$ for 5 minutes and the solution clarified by removing the agglutinate was used as the antigen solution. Antibody-sensitized erythrocyte solution was prepared from sheep erythrocytes sensitized by rice stripe virus with tannic acid, and its agglutination titer was 1 : 512. The virus concentrations in flag leaves or first leaves just below them showing different symptoms was high with progressing the severity of symptoms. And the concentrations of the virus in leaves of varieties of the rice plant showing same degree symptom were lower in suscetible varieties, Sadominori, Palgoeng, Mangyong and Nihonbare, than in the resistant one, Tongil, but in Yooshin which was known as the resistant, lower rather than in Tongil. The reacton of antibody-sensitized hemagglutination test to inspect the virus carrier, was so highly sensitive that this reaction was recognized as a method which is able to Identify the carrier accurately in short time.

• Korean Journal of Veterinary Research
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• v.62 no.4
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• pp.29.1-29.7
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• 2022

Vaccination against Newcastle disease (ND) is the most effective means of controlling the disease, and these vaccines are commercialized only after their safety and effectiveness have been verified through tests that comply with Korean Standards of National Lot Release for Veterinary Biologics. This study investigated whether a relatively convenient and safe serological test can be used in place of the challenge test using highly virulent ND virus. Hemagglutination inhibition (HI) assay and enzyme-linked immunosorbent assay (ELISA) were considered positive of log₂ 2 or more and cutoff value of 200 or more, respectively, in both live and inactivated vaccines. However, when the antibody levels of the live and inactivated vaccines induced using the Ulster 2C, KBNP-C4152R2L, and K148/08 strains were compared, the antibody titers for inactivated vaccines were significantly higher than those for live vaccines in both the HI assay and ELISA. A strong positive correlation was observed between HI and ELISA antibody titers. The live vaccines corresponded to a survival rates of ≥ 80% and the inactivated vaccines corresponded to 100% survival rates. This study confirmed that standard efficacy tests can serve as serological tests, and can replace the challenge test and that the vaccine approval process can be improved.

• BMB Reports
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• v.29 no.3
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• pp.192-199
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• 1996

A rapid and sensitive method has been developed to detect a-fetoprotein (AFP) in human serum by a two-site sandwich enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies (MAbs) for human AFP within 1 h. To obtain the most sensitive and reliable MAbs. 12 kinds of MAbs (HPJ1 to HPJ12) as a capture antibody and 4 kinds of horseradish peroxidase (HRP) conjugated MAbs as a tracer antibody were investigated. Among these, only HPJ 10-HRP conjugated HPJ 1 (HPJ 10-HPJ $1^*$) and HPJ 11-HRP conjugated HPJ 10 (HPJ 11-HPJ $10^*$) were chosen as candidates based on the linearity of the standard curve and the sensitivity of the assay. To further characterize these two pairs. MAbs against human AFP were purified from hybridoma cells. conjugated with HRP. and then characterized to optimize the two-site sandwich ELISA The HPJ 10-HPJ $1^*$ pair showed a sensitivity of 1 ng/ml and a better reproducibility than the HPJ 11-HPJ $10^*$ pair when the human sera were incubated at $37^{\circ}C$ for 30 min. The results obtained for 480 randomly selected human sera showed 0~20 ng/ml of AFP values for the normal human sera. To test the utility of our kit, AFP concentrations were determined for 951 human sera (including 85 normal sera, 480 random blood sera, 213 HBsAg-positives. 50 anti-HCV antibody positives. and 47 malignant diseases) and compared with other commercially available AFP detecting kits. These results show that the present two-site sandwich ELISA method is a rapid, sensitive, and reliable procedure for detecting AFP in human serum.

• Korean Journal of Poultry Science
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• v.15 no.3
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• pp.207-210
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• 1988

A total of 3 hybridoma clones producting menoclonal antibody (MCA) against Newcastle disease virus(NDV) was raised by cell fusion method. The MCAs did not cross react against other avian or mammalian viruses tested. However, these antibodies reacted with all strains of velogenic and lentogenic NDVs tested indicating that they are unable to discriminate the possible antigenic differences among NDVs. All. the MCAs were classified as IgG type and did not show neutralizing and hemagglutination inhibition (HAI) activity except one clone which has low HAI activity. One of these MCA raised in mouse ascites revealed the titer of $10^6$ by indirect immunofluorescent antibody (IFA) test Using the MCA, virulent NDV could easily be detected from tracheal and conjunctival smears made 2 to 3 days after experimental infection.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.261-261
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• 1994

Bovine milk xanthine oxidase (E.C.1.1.3.22, XO) purchased from Sigma Chemical Co. had the three protein fragments below 150 kDa on 7.5％ SDS-PAGE, which did not show enzyme activity. To remove these fragments, the enzyme preparation was further purified through Sephadex G-200 column chromatography. Two peaks exhibiting enzymatic activity were separated very closely to the void volume, which were revealed as two different enzyme forms, dimeric and monomeric, confirmed by activity staining on native PAGE. Anti sera-against each of the two enzyme forms were raised by subcutaneous injection at multiple sites on the back of rabbits during 4 weeks. On the immunodiffusion test, it was found that both of the antisera of the two forms could react with each other, which implied that their epitopes were identical In the Western blot analysis of mouse liver cytosol fraction, it was found that rabbit anti-XO antibody bound well with the protein band of monomeric mouse liver XO of about 150kDa. Based on this result, mouse liver cDNA 1 ibrary was screened by in situ hybridizat ion wi th rabbi t anti -XO antibody as probe. Through the immunological screening, recombinant phages giving positive signal by the production of XO were selected and further purified. To validate these clones, purified phages were lysogenized in E. coli Y1089 and their lysates were analysed for enzyme activity and immunoreactivity, It was verified that lysates of the purified recombinant phage lysogens exhibited the enzymatic activity as well as bound wi th XO antibody, when induced by IPTG. The above results assert that selected recombinant phage carries mouse liver XO gene.

• The Journal of the Korean Society for Microbiology
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• v.21 no.3
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• pp.387-391
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• 1986

Serum samples from 51 patients with clinically suspected typhoid fever were tested for immunoglobulin G (IgG), IgM and IgA antibodies against the whole bacteria antigen of Salmonella typhi by an enzyme-linked immunosorbent assay. The levels of IgG and IgA antibody to-whole bacteria antigen were higher in the culture-proven patients than in controls. The levels of IgM antibody to- whole bacteria antigen showed better discrimination between culture negative patients and controls than those of IgG or IgA antibody to-whole bacteria antigen. The enzyme-linked immunosorbent assay was much more sensitive than the Widal test. It would be a useful tool for the diagnosis of typhoid fever with a single serum sample.

• Korean Journal of Veterinary Research
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• v.43 no.1
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• pp.129-137
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• 2003

Porcine reproductive and respiratory syndrome (PRRS) is characterized by reproductive failures in sows and respiratory problems in piglets. The nucleocapsid(N) protein, encoded by the open reading frame 7 (ORF7) gene, is known to be the most abundant and antigenic protein in PRRS virus. Therefore, it was suggested that the N protein could be a suitable candidate for the detection of PRRS virus-specific antibodies and diagnosis of PRRS. In the present study, the ORF7 gene encoding the N protein was cloned and expressed as a fusion protein with the glutathione S-transferase (GST) in Escherichia coli. The resulting GST-N recombinant protein was used as an antigen for an indirect sandwich enzyme-linked immunosorbent assay (i-ELISA). Expressed GST-N recombinant protein was migrated at 41 kDa and reacted with ORF7-specific monoclonal antibody by Western blotting. In order to increase the specificity of the ELISA for the detection of PRRS virus-specific antibodes, an i-ELISA was developed using an anti-GST antibody as a capture antibody. The sensitivity and specificity of developed i-ELISA were 92% and 96%, respectively. Based on these results, it was suggested that the i-ELISA is a simple and rapid test for screening a large number of swine sera for the anti-PRRS virus antibodies.