• 대한수의학회지
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• 제50권3호
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• pp.205-211
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• 2010

Fifty young calves, about five to six months old purchased from nation-wide were investigated with the prevelance of neutralizing antibody (Ab) of infectious bovine rhinotracheitis virus (IBRV), parainfluenza 3 virus ($PI_{3}V$), bovine viral diarrhea virus (BVDV) and bovine respiratory syncytial virus (BRSV). The positive detection ratio of neutralizing Ab against IBRV was only 3% and two of positive samples showed low antibody titer (below 2). Ab against BRSV showed 48% of positive ratio and among 24 positive samples, antibody titer of 23 samples were below 3. But in the case of BVDV, 68% of samples were positive and 23 samples appeared to possess high antibody titer, above 4 and the antibody titer of five samples were above 8. The highest positive result came from $PI_{3}V$. The positive ratio in the samples investigated in this study was 72%, but the antibody titer of positive samples were generally below 3 (77.8% in positive samples).

• Biomolecules & Therapeutics
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• 제10권3호
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• pp.175-179
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• 2002

Human growth hormone (hGH) forms antibody by repeated administration. The present study investigated to confirm formation of antibody by repeated subcutaneous administration of hGH for two months in rats and dogs. In this result, hGH-injected sera were significantly higher than control sera by 1:1,000,000 of dilution factor. After antibody formed sera (anti-hGH sera) and control sera were added to 30 $\mu\textrm{g}$/ml hGR, the complex incubated for overnight at $30^{\circ}C$. Anti-hGH sera decreased hGH contents about 90% compared to control sera. Also, body weight gain conducted decreased about 67% compared to control sera in hypophysectomised rat. Inconclusion, repeated administration of hGH formed antibody because hGH was foreign protein to rats and dogs. And formed antibody of hGH was blocked and decreased many efficacy of hGH, the antibody was proved to be neutralizing antibody. Thus, because neutralizing antibodies were decreased pharmacological effects of hGH, administration more than two months were no significance.

• 대한수의학회지
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• 제32권1호
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• pp.83-90
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• 1992

소 설사병 바이러스 구조단백에 대한 단크론항체를 작성하여 혈청중화시험, 전기영동, 면역침전반응을 이용하여 분석하였던 바 다음의 결과를 얻었다. 중화능력이 있는 항체의 경우 56K내지 54K의 구조단백에 대응하였다. 그외 중화력을 나타내지 않는 항체는 45K와 36K의 바이러스 항원과 대응하였다. 순수정제된 바이러스의 전기영동 분석결과 12종 이상의 바이러스 단백성분이 구조단백질로서 검출되었으며 중화능력을 나타내는 항체를 이용한 면역침전 결과는 이들의 존재를 뒷받침하였다. 중화단백성분의 세포내 전구물질의 검출은 불가능하였으나 방사선동위원소 부착즉시 세포배지에서 바이러스의 존재를 확인할 수 있었다. Staphylococcus aureus $V_8$효소를 이용한 항원의 부분소화 분석결과 45K와 36K의 바이러스 항원은 서로 상관이 있는 것으로서 입증되었다.

• 한국임상수의학회지
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• 제26권5호
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• pp.423-428
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• 2009

There were outbreaks of canine distemper in Korea from the late 1990's to the early 2000's even though modified live CDV vaccines had been used as the same way as before. The present study was undertaken to investigate the levels of neutralizing antibodies in the Korean dog population, and the factors associated with the levels, with special reference to the vaccination history of the dogs. A total of 772 serum samples were from clinically healthy dogs with over one year old throughout the Korea from January 2003 to April 2004. Details on the sex, breed, age, vaccination status and disease histories were recorded. The level of neutralizing antibodies titer was determined with a modified version of the microneutralization test. Titers over 16 were classified as protective CDV antibody titers. The overall rate of adult dogs with protective antibody titers was 96.0%. The dogs with protective antibody titers varied depending on age, sex, rearing environment and vaccination status. Because the majority of healthy adult dogs in Korea had adequate serum antibody titers against CDV and the immunity provided by the vaccinations is claimed to last for several years, annual revaccination protocol for CDV in adult dogs should be reconsidered.

• 대한미생물학회지
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• 제22권4호
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• pp.377-392
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• 1987

Monoclonal antibody to the Escherichia coli heat-stable enterotoxin(ST) was produced to develop a rapid and convenient diagnostic method to the ST. The toxin was purified from culture supernatant of enterotoxigenic E. coli O148H28($ST^+/LT^+$) and conjugated to bovine serum albumin(BSA). The ST-BSA conjugate was used to immunize BALB/c mice and the immune spleen cells from these mice were fused with $P3{\times}63$ Ag8.V653 plasmacytoma cells. Hybridomas were screened by ELISA and positive hybridomas were cloned by limiting dilution. Finally, one stable clone (AS36) specific to ST was selected for further growth and characterization. Antibody titers of culture supernatant and ascitic fluid from BALB/c mice were 1:1,024 and 1:20,480 respectively in ELISA. The isotype and subclass of monoclonal antibody was IgG1 in sandwich ELISA. To test the neutralizing effect of monoclonal antibody on toxin activity of ST, mixture of ascitic fluid and ST was assayed by infant mouse assay and this monoclonel antibody was proved to be a neutralizing antibody. The titer of ascitic fluid which completely neutralized biological activity of 4 units of ST was 1:4. Purified ST was quantitatively measured by competitive ELISA and minimum amount of ST detectable by this assay was 250pg, which was an amount six-fold smaller than that detectable by infant mouse assay. Four reference strains of enterotoxigenic E. coli from WHO were detected by competitive ELISA and highly specific, sensitive and reproducible result was obtained.

• 대한수의학회지
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• 제8권1호
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• pp.24-30
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• 1968

From 1962 to 1968, serum samples were collected from fowls of six provinces in Korea. The investigator tested for serum neutralizing antibody against the Beaudette strain of intecfious bronchitis virus. Twenty(40 percent)serum samples out of fifty revealed a neutralization index of more than 30. Neuralizing antibodies of infectious bronchitis virus are widely spread among chickens in Korea. Intensive poultry farming zones, adult chickens have been neutralizing antibody of infectious bronchitis virus.

• 한국동물위생학회지
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• 제17권1호
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• pp.1-8
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• 1994

To investigate serum neutralizing antibodies against Bovine ephemeral fever (BEF) virus, Akabane virus and Ibaraki virus in southern area of Chungnam province, Holstein sera were collected from April-May(269 heads /37 farms) and October-November (226 heads /35 farms), 1993. The results were summarized as follows ; 1. Bovine ephemeral fever.-antibody positive rates to BEF virus were 46.1% (124 heads /269 Holstein) in April-May and 53.9%(122 heads /226 Holstein) in October-November. 2. Akabane disease.-antibody positive rates to Akabne virus were 34.2％(92 heads /269 holstein) in April-May and 51.3%(116 heads /226 Holstein) in October-Novermber. 3. Ibaraki disease.-antibody positive rates to Ibaraki virus were 57.6%(155 heads /269 Holstein) in April -May and 38.5%(87 heads /226 Holstein) in October-November.

• Molecules and Cells
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• 제44권6호
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• pp.392-400
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• 2021

It has been more than a year since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first emerged. Many studies have provided insights into the various aspects of the immune response in coronavirus disease 2019 (COVID-19). Especially for antibody treatment and vaccine development, humoral immunity to SARS-CoV-2 has been studied extensively, though there is still much that is unknown and controversial. Here, we introduce key discoveries on the humoral immune responses in COVID-19, including the immune dynamics of antibody responses and correlations with disease severity, neutralizing antibodies and their cross-reactivity, how long the antibody and memory B-cell responses last, aberrant autoreactive antibodies generated in COVID-19 patients, and the efficacy of currently available therapeutic antibodies and vaccines against circulating SARS-CoV-2 variants, and highlight gaps in the current knowledge.

• 한국식품영양과학회지
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• 제29권1호
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• pp.128-133
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• 2000

This study was designed to verify the efficacy of garlic extracts for protecting the infecton of influenza and Japanese B encephalitis virus. Influenza virus (AO/PR8 strain) and Japanese B encephalitis virus (JaGAr O1 strain) were used to attack mouse through nasal route and each vaccines were injected subcutaneously. 0.002 and 0.2 mL/day of garlic extracts were orally administered to mice. The blood and serum samples were taken from the mice to measure LD50, Defense Index (DI), virus-neutralizing antibody for comparing virus influence inhibiting activities. Defense indices of the male and female mice were not significantly different at every experiment. Vaccination effectively inhibited the influence of influenza virus and 0.002 mL/day garlic extract (0.55$\pm$0.05) resulted in significantly higher DI than the control (0$\pm$0.05) (p<0.05). Although 0.002 mL/day garlic extract (0.55$\pm$0.05) resulted in significantly lower DI than the vaccination (1.10$\pm$0.05), 0.2 mL/day garlic extract (2.05$\pm$0.05) resulted in 10 times higher DI than the vaccination (1.10$\pm$0.05). Garlic extract did not affect DI in Japanese B encephalitis virus influence of the vaccinated mouse, but significantly reduced DI of the non-vaccinated mouse (p<0.05). Garlic extracts did not affect the production of the neutralizing antibody against influenza by vaccination. However, neutralizing antibody production of Japanese B encephalitis was accelerated by vaccination. Consequently, the current study proved the efficacy of garlic on inhibition of influenza virus. Finally, it is very hard to show the higher preventing effect on flu through ingestion of garlic as a food than vaccination.

• 한국동물위생학회지
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• 제26권1호
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• pp.73-80
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• 2003

In order to obtain information on murine model for foot and mouth disease virus(FMDV) type Asia 1, we studied whether guinea pig was a suitable model for studying FMDV. Apparently healthy 3 months old albino guinea pigs and unweaned 3 days old Swiss albino mice were used for this study. Total of 8 guinea pigs were divided into the infected(n=5) and control(n=3) groups. The incubation period of FMDV in the guinea pigs were roughly 2 days and the viremia persisted for 3 days in the guinea pigs. Mice inoculated with the plasma from control guinea pigs did not show any sign of viremia. The plasma were titrated by virus neutralization test using suckling mice as an indicator host. The mean virus neutralizing antibody titers of infected guinea pig at 3 DPI, 4 DPI and 5 DPI were log$\_$10/2.16, log$\_$10/ 3.39 and log$\_$10/ 3.44, respectively whereas there was no neutralizing antibody titer in control group. The difference between the mortality pattern and mean virus neutralizing antibody titer of infected and that of control group at day 3, 4, 5 were statistically significant(p<0.0l).