• 대한의생명과학회지
• /
• 제8권4호
• /
• pp.269-273
• /
• 2002

Dengue fever (DF) is an acute febrile illness caused by dengue viruses in the family Flaviviridae, genus Flavivirus. DF has so far posed any problem in Korea, however it has been recently believed to be associated with oversea's traveler infected with dengue virus. Antibody titers of sera from DF patients against dengue virus were measured by indirect immunofluorescence assay (IFA) and plaque reduction neutralization test (PRNT), including the haematologic test. Three of patients with DF showed highly fluorescent and neutralizing antibody titers by IFA and PRNT assay. Two of them showed higher, remarkably. Meanwhile, one of them was tested and resulted in severe tirombocytopenia, elevated serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) activities as well as mild leucopenia, increased monocytes and basophils and depressed lymphocytes in haematological differential count.

• 대한미생물학회지
• /
• 제22권1호
• /
• pp.1-8
• /
• 1987

Hantaan virus(HV) 76-118 strain was inoculated into suckling ICR mice by intra-nasal route with an inoculum of $10LD_{50}$. Mortality was 65% at the 3rd week after inoculation, but declined to 35% at the 4th week. Infectivity was determined by the measuring immuno-fluorescent antibody in sera. The peak of infectivity was 80% at the 4'th week after inoculation. Viremia was reached peak level of $1.7{\times}10^4\;PFU/ml$ by day 10. Immunofluorescent antibody and neutralizing antibody appeared by 2 weeks and 15-17 days respectively, but achieved similar titer by 35 days. By using a monoclonal antibody to HV 76-118, viral antigens were initially detected in inguinal and axillary lymph node by 2 days. Viral antigens in bone marrow and lung were delayed much more than in those of lymph node. These were similar with those of intra-peritoneal and intra-muscular route. Immune complex against IgG, IgM and C3 appeared by 16 days, 14 days, and 18 days respectively. The pattern of immunofluorescence in the basement membrane of glomeruli was diffuse membranous. Spotted pattern was also observed in the tissue stained with anti-mouse C3 antibody. By 20 days, control tissue was also shown immune complex in the glomeruli.

• 한국동물위생학회지
• /
• 제25권1호
• /
• pp.1-7
• /
• 2002

Recently, the rabies cases have been reported in Paju- and Yangju-gun, Gyeonggj province near Seoul metropolitan area. The Pukhansan national park, nearly located from the cities, is suspected to be a high risk area for incidence and spread of the rabies to metropolitan area. This study was conducted to investigate the prevalence rate for rabies antibody of dogs near the Pukhansan national park and in some other districts in Seoul metropolitan city. From march to october 2001, a total of 306 serum samples were taken from dogs for breeding(189) md pet dogs(117) in 4 districts near the Pukhansan national park and other districts of Seoul. Rabies virus antibodies in sera were detected by neutralizing peroxidase - linked as say (NPLA). Of the 306 sera of dogs tested, 74 (24.2%) were positive to rabies virus antibody. The prevalence rates of rabies antibody in Pukhansan national park area and in the other districts of Seoul city were 23.7% and 25.3%, respectively There was no significant difference in the prevalence rate between these two districts. The prevalence rates of rabies antibody in pet dogs and dogs for breeding were 40.2% and 14.3% respectively. The prevalence rates of rabies antibodies in less than 1 year, 1∼<2 years, 2∼<3 years, and over 3 years old dogs were 14.5%, 22.4%, 32.6%, and 27.1%, respectively, and overall 24.2% in the dog population. In addition, we found that dogs less than 1 year old had lower antibody prevalence than those over 1 year old. It was concluded that enhancement of vaccination is important in the prevention of the rabies, and that rabies vaccines should not be less supplied than the population of the dog.

• 대한바이러스학회지
• /
• 제26권2호
• /
• pp.163-171
• /
• 1996

The recombinant pseudorabies virus major capsid protein (rMCP) was produced by expression of the MCP gene in Sf-9 cell using baculovirus transfer vector system. Following evaluation of the immunochemical properties of the rMCP, the immunogenicity of the recombinant subunit protiens were investigated in guinea pig and swine to obtain the preliminary guide line for the subunit vaccine using rMCP and gP50. It was proved that ultrasonication and 30% ammonium sulfate was most efficient to concentrate and purify the protein. The rMCP was safe in mice, guinea pigs and piglets. In guinea pigs, rMCP mixed with various adjuvants induced substantial degree of serum neutralizing antibody titers, but revealed incomplete protectivity against challenge. In swine, the combination of rMCP and gP50 showed the higher serum neutralizing antibody titers and cellular immune responses than rMCP alone. However, the protectivity was lower in comparison with the commercial gI-deleted inactivated vaccine. We expect these results to contribute to characterization of MCP gene of Korean isolate of PRV and to ultilize as preliminary information for prodution and evaluation of PRV recombinant subunit vaccines.

• 생명과학회지
• /
• 제19권9호
• /
• pp.1304-1308
• /
• 2009

To investigate the infection patterns of porcine epidemic diarrhea virus (PEDV) in Korean pig farms, a total of 4,768 swine sera samples from 159 pig farms were taken twice, in June (n=82) and October (n=77) in 2007. In each farm selected for the survey, 10 samples from breeding pigs and 4 from each of the 5 age groups (30, 60, 90, 120, and 150 days) were taken, and all serum samples were tested for PEDV by the serum neutralization test. The overall seroprevalence was 62.6% (2,983/4,768), with the highest prevalence in breeding pigs (93.5%, 1,485/1,589). The prevalence showed an increasing trend with increasing age (30.8, 27.2, 44.7, 61.6, and 71.2% respectively in the 30, 60, 90, 120, and 150 days age groups) (p<0.0001 for $x^2$ trend test). The association between age and PEDV prevalence was similar in both surveys, indicating that the infection of PEDV seemed to be occurring repeatedly in the farms surveyed. This inference could also be explained by the fact that prevalence in sows was very high despite low vaccination coverage, as they are continuously exposed to PEDV in potentially infected farms for a longer period. Based on the neutralizing antibody levels in sows and growing pigs, the majority of farms (91.8%, n=146 farms) were endemically infected with PEDV, and most of pigs seemed to be intensively infected with PEDV at around early growth (41.8%) and weaning (31.5%). On the other hand, serum neutralizing antibodies were not detected in pigs older than 30 days of age in farms classified as having no PEDV infection (n=13 farms), indicating the level of maternal antibody against PEDV is decreased on a non-detectable level before the piglet is 60 days old in the field situation. The results indicated that most farms surveyed in 2007 were affected with endemic PEDV infection. Therefore, a national monitoring and control program for the endemic type PEDV infection needs further attention.

• 대한바이러스학회지
• /
• 제27권2호
• /
• pp.209-216
• /
• 1997

Three dimensional structures of envelope protein from Korean isolates and Nakayama-NIH strain of Japanese encephalitis virus (JEV) were deduced by a computer program (HyperChem 4.0 Chemplus 1.0) based on the data of the three dimentional structure of Tick-borne encephalitis virus. In the three dimensional structure of envelope protein, neutralizing epitope and T-helper cell recognition site of C-terminal region of Korean isolates were structually similar to those of Nakayama-NIH but the N-terminal region was not. Korean JE isolates were compared with Nakayama-NIH strain by using cross-neutralization antibody test. Neutralizing activities of Korean isolates derived from guinea pigs were higher than those of Nakayama-NIH strain against Korean isolates, although the polyclonal antibody titers of Nakayama-NlH showed 1:160 to 1:640 against Korean isolates. According to the results from three dimentional structures and cross-neutralization analyses, the antigenic difference between Korean JE isolates and Nakayama-NIH strain may be dependent on structural difference of envelope protein.

• 한국임상수의학회지
• /
• 제11권2호
• /
• pp.585-592
• /
• 1994

A consecutive Jiao Chio acupuncture therapy was performed for 3 days in the 45-90 days old 11 calves of which have been shown severe watery diarrhea. The discharge of the infected calves was yellowish brown in color. Two calves of these patients were infected wi pulmonary disease as well as diarrhea. Thus, Su Qi and Fei Yu acupuncture therapy was carried out additionally after dosing with antibiotics twice for The two infected calves. Blood chemical values and serum neutralizing antibody titers were checked, and total blood cell count was also carried out to know the therapeutic effect before and after(21 days) acupuncture therapeutics. The results are as follows ; 1, The diarrhea has ceased one day after begining of the acupuncture therapy in 5 calves, and the cessation of the diarrhea in remaining calves occurred in 1 calf each on 3rd and 4th day, and 2 calves on 6th day, respectively. Two calves infected with pulmonary disease as well diarrhea were cured 8 days after the begining of the therapcutics. 2. Rotaviruses wire detected in the feces of 2 calves, and bovine diarrhea viruses were detected in the 8 calves by the test for serum neutralizing antibody titers, and bovine coronaviruses were also detected in 5 calves. Four calves of the 5 bovine coronavirus infected calves were also infected with bovine diarrhea viruses. 3. Total leucocyte number, total amount of serum protein, and amount of fibringen were slightly increased, while total erythrocyte number, and erythrocyte packed cell volume were slightly decreased. These valucs were statistically not significant. Electrolytes of Na/sup +/, K/sup +/ and Cl/sup -/ were slightly decreased but these values also were not significant. These results indicate that the acupuncture therapeutics arc significantly effective to remove the viral diarrhea in the young calves.

• 대한한방내과학회지
• /
• 제24권1호
• /
• pp.123-133
• /
• 2003

Objectives : This study was designed to investigate the effects of Chungganhaeju-tang on expression of alcohol metabolizing enzymes, cell viability and alcohol-induced apoptosis. Materials and Methods : For this study, the human hepatoma cell line HepG2 was used. HepG2 cells were treated with ethanol-or acetaldehyde, chungganhaeju-tang, anti-Fas neutralizing antibody and were investigated by using quantitative RT-PCR, MTT and Trypan blue exclusion assays. Results : The results are summarized as follows: 1. Quantitative RT-PCR analysis demonstrated that ethanol-or acetaldehyde-mediated increase of ALDH gene expression was not affected by Chungganhaeju-tang treatment. 2, Ethanol-or acetaldehyde-induced apoptosis was remarkably inhibited by Chungganhaeju-tang in a dose-dependent manner. 3, Ethanol-or acetaldehyde-induced apoptosis was significantly blocked by anti-FasL neutralizing antibody, suggesting apoptosis induced by alcohol might be mediated by FasL/Fas signaling pathway. Conclusions : Taken all together, these results indicate that the FasL/Fas signaling plays a critical role in alcohol-induced apoptosis and Chungganhaeju-tang increases viability of liver cells by suppression of the FasL/Fas-mediated apoptosis-signaling pathway.

• 한국동물위생학회지
• /
• 제34권1호
• /
• pp.5-12
• /
• 2011

Infectious bursal disease (IBD) caused by infectious bursal disease virus (IBDV) is a highly contagious viral disease in chicken. It causes heavy economic loss by immune suppression and high mortality. The IBDV, designated Avibirnavirus in the Family Birnaviridae, has a double-stranded RNA genome formed by two segments, segment A and segment B. Segment A encodes a 108 KDa polypeptide that is self-cleaved to produce pVP2, VP3 and VP4, and later pVP2 is cleaved to VP2. The VP2 contains the antigenic regions responsible for elicitation of neutralizing antibodies and VP3 is a major immunogenic protein of IBDV. In this study, monoclonal antibodies (MAbs) specific for IBDV were produced and characterized. All 15 MAbs were specific for IBDV and did not react with other viruses used in this study. The protein specificity of MAbs was determined by comparing the reactivity patterns of each MAb with IBDV VP2 and VP234 recombinant baculoviruses and Western blot analysis. As a result, 7 MAbs (1F5, 2C8, 2F4, 3C7, 4C3, 6F11, 6G5) and 5 MAbs (2A4, 2G2, 3F5, 3G2, 4F10) were specific for VP2 and VP3, respectively. The protein specificity of 3 MAbs (2B8, 3F7, 3F8) were not determined. Five (2C8, 2F4, 4C3, 6F11, 6G5) of the VP2-specific MAbs had a neutralizing activity against IBDV. Some MAbs reacted with IBDV-infected bursa of Fabricius by indirect fluorescence antibody (IFA) and immunohistochemistry (IHC) assay. The MAbs produced in this study would be used for diagnostic reagents for the detection of IBDV infection.

• IMMUNE NETWORK
• /
• 제21권6호
• /
• pp.39.1-39.18
• /
• 2021

The high virulent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that emerged in China at the end of 2019 has generated novel coronavirus disease, coronavirus disease 2019 (COVID-19), causing a pandemic worldwide. Every country has made great efforts to struggle against SARS-CoV-2 infection, including massive vaccination, immunological patients' surveillance, and the utilization of convalescence plasma for COVID-19 therapy. These efforts are associated with the attempts to increase the titers of SARS-CoV-2 neutralizing Abs (nAbs) generated either after infection or vaccination that represent the body's immune status. As there is no standard therapy for COVID-19 yet, virus eradication will mainly depend on these nAbs contents in the body. Therefore, serological nAbs neutralization assays become a requirement for researchers and clinicians to measure nAbs titers. Different platforms have been developed to evaluate nAbs titers utilizing various epitopes sources, including neutralization assays based on the live virus, pseudovirus, and neutralization assays utilizing recombinant SARS-CoV-2 S glycoprotein receptor binding site, receptor-binding domain. As a standard neutralization assay, the plaque reduction neutralization test (PRNT) requires isolation and propagation of live pathogenic SARS-CoV-2 virus conducted in a BSL-3 containment. Hence, other surrogate neutralization assays relevant to the PRNT play important alternatives that offer better safety besides facilitating high throughput analyses. This review discusses the current neutralization assay platforms used to evaluate nAbs, their techniques, advantages, and limitations.