• Korean Journal of Veterinary Research
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• v.63 no.1
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• pp.5.1-5.9
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• 2023

Feline panleukopenia virus (FPV), feline calicivirus (FCV), and feline herpesvirus type-1 (FHV-1) are major infectious pathogens in cats. We evaluated the immunogenicity of a new vaccine containing inactivated FPV, two FCVs, and FHV-1 in animals. An FPV, two FCVs, and an FHV-1 isolate were continuously passaged 70, 50, 80, and 100 times in CRFK cells. FP70, FC50, FC80, and FH100 were propagated and used as vaccine antigens. Two inactivated feline virus vaccines, feline rehydragel-adjuvanted vaccine (FRAV) and feline cabopol-adjuvanted vaccine (FCAV) were prepared and inoculated into mice and guinea pigs. Humoral immune responses were measured using hemagglutination inhibition (HI) for FPV and virus-neutralizing antibody (VNA) for two FCVs and FHV-1 tests. Serial passages in CRFK cells resulted in increase in titers of FPV and two FCVs but not FHV-1 The FCAV induced higher mean HI and VNA titers than the FRAV in guinea pigs; therefore, the FCAV was selected. Cats inoculated with FCAV developed a mean HI titer of 259.9 against FPV, and VNA titers of 64, 256, and 3.2 against FCV17D03, FCV17D283, and FHV191071, respectively. Therefore, cats inoculated with the FCAV showed a considerable immune response after receiving a booster vaccination.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.177-186
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• 1990

To investigate the etiology, pathogenicity and virological properties of NYJ-1-87 strain of Aujeszky's disease virus (ADV) that was isolated from the diseased piglet in Korea, the virus at $10^{6.0}TCID_{50}/0.1ml$ was inoculated intranasally and subcutaneously into 30 to 35 days-old piglets. Results obtained through the experiments were summarized as follows. 1. Ten of the infected piglets were clinically observed for 15 days. On the 2nd day post-inoculation(pi), the signs of pyrexia, anorexia and convulsion were noted. On the 4th to 7th days pi, nervous signs of incoordination and intermittent spasm were shown in the most of piglets, and one out of 5 piglets infected intranasally was died with severe nervous signs at the 7th day pi. The signs became relieved on the 8th day pi and all of remainder were completely recovered on the 13th to 14th days pi. 2. In hematological study, prominent decrease in the number of total leukocyte and lymphocyte was shown in the ADV-infected piglets on the 6th day pi. On the 8th day pi, the cell numbers were slightly increased and returned to normal level on the 10th day pi. 3. Viral excretion of the ADV-inoculated piglets was examined by swabbing of nasal and oral cavities, and rectal feces. During the periods of the 3rd to 11th days pi, the virus was excreted intermittently from nasal and oral cavities, and rectal feces. The nasal excretions were shown the highest virus concentration of $10^{5.2}TCID_{50}/0.1ml$ at the 5th day pi. 4. Recovery of the inoculated virus from various organs of the piglets that were died or experimentally slaughtered was attempted, and the virus was isolated from the tissues of brain and tonsil by the cultured cell-inoculation method. The highest recovery rate was noted in the tonsil. By indirect immunofluorescence antibody assay using ADV-monoclonal antibody, the viral antigens were detected in tissues of spleen and liver as well as brain and tonsil on the 7th to 9th days pi. The virus was not isolated from blood and the tissues of lung and kidney throughout the experiments. 5. Titers of virus neutralizing antibody in the piglets experimentally infected with ADV became increased after the 6th to 9th days pi in both of intranasal and subcutaneous inoculation showing the highest titers of 64 to 128 on the 29th day pi. When the antibody levels were measured by radial immunodiffusion enzyme assay, the reactive diameter was enlarged to be positive after the 4th to 6th days pi in both of intranasal and subcutaneous inoculation showing the largest diameter of 13 to 14mm on the 29th day pi.

• Korean Journal of Veterinary Service
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• v.32 no.3
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• pp.177-187
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• 2009

The purpose of this study was to evaluate the effect of a subsequent infection of PCV2 on piglets with PEDV. The results obtained were as follows: Antibodies against PCV2 and PEDV were detected at 24, 36, 48, 60 and 72h postinfection. And the antibody titers of alone infections with PEDV were gradually reduced and increased from 60 hpi to 72 hpi. Whereas, the antibody titers of dual infections with PCV2 and PEDV were gradually reduced all the time. PEDV antigens were detected at 24, 36, 48, 60 and 72 hpi, being seen almost exclusively in feces and small intestines from PEDV-infected piglets and PCV2-coinfected piglets. The detection rate of PEDV in feces and jejunum tissues by RT-PCR were 94.9% and 91.1% in dual infections and 87.1% and 83.6% in alone infections with PEDV, respectively. In dual infected piglets, significantly more PEDV antigens were detected in the feces and small intestines tissues at 24 hpi (P<0.05) than in the same feces and tissues of the alone infected piglets. Thereafter, at 72 hpi significantly more PEDV antigens (P<0.05) was detected in the jejunal tissues of the dual infected piglets with than of alone PEDV-infected piglets. The detection rate of PEDV antigen in the duodenum, jejunum and ileum by IFA were 91.3%, 91.3% and 83.3% in dual infected piglets and 75.0%, 83% and 75% in alone infected piglets, respectively. Intense and specific fluorescence signals were more often seen within jejunal villous enterocytes in dual infected piglets than alone infected piglets.

• IMMUNE NETWORK
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• v.6 no.2
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• pp.102-110
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• 2006

Background: Dendritic cells (DC) are professional antigen-presenting cells in the immune system and can induce T cell response against virus infections, microbial pathogens, and tumors. Therefore, immunization using DC loaded with tumor-associated antigens (TAAs) is a powerful method of inducing anti-tumor immunity. For induction of effective anti-tumor immunity, antigens should be efficiently introduced into DC and presented on MHC class I molecules at high levels to activate antigen-specific $CD8^+$ T cells. We have been exploring methods for loading exogenous antigens into APC with high efficiency of Ag presentation. In this study, we tested the effect of the cationic liposome (Lipofectin) for transferring and loading exogenous model antigen (OVA protein) into BM-DC. Methods: Bone marrow-derived DC (EM-DC) were incubated with OVA-Lipofectin complexes and then co-cultured with B3Z cells. B3Z activation, which is expressed as the amount of ${\beta}$-galactosidase induced by TCR stimulation, was determined by an enzymatic assay using ${\beta}$-gal assay system. C57BL/6 mice were immunized with OVA-pulsed DC to monitor the in vivo vaccination effect. After vaccination, mice were inoculated with EG7-OVA tumor cells. Results: BM-DC pulsed with OVA-Lipofectin complexes showed more efficient presentation of OVA-peptide on MHC class I molecules than soluble OVA-pulsed DC. OVA-Lipofectin complexes-pulsed DC pretreated with an inhibitor of MHC class I-mediated antigen presentation, brefeldin A, showed reduced ability in presenting OVA peptide on their surface MHC class I molecules. Finally, immunization of OVA-Lipofectin complexes-pulsed DC protected mice against subsequent tumor challenge. Conclusion: Our data provide evidence that antigen-loading into DC using Lipofectin can promote MHC class I- restricted antigen presentation. Therefore, antigen-loading into DC using Lipofectin can be one of several useful tools for achieving efficient induction of antigen-specific immunity in DC-based immunotherapy.

• IMMUNE NETWORK
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• v.21 no.1
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• pp.11.1-11.10
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• 2021

Coronavirus causes an infectious disease in various species and crosses the species barriers leading to the outbreak of zoonotic diseases. Due to the respiratory diseases are mainly caused in humans and viruses are replicated and excreted through the respiratory tract, the nasal fluid and sputum are mainly used for diagnosis. Early diagnosis of coronavirus plays an important role in preventing its spread and is essential for quarantine policies. For rapid decision and prompt triage of infected host, the immunochromatographic assay (ICA) has been widely used for point of care testing. However, when the ICA is applied to an expectorated sputum in which antigens are present, the viscosity of sputum interferes with the migration of the antigens on the test strip. To overcome this limitation, it is necessary to use a mucolytic agent without affecting the antigens. In this study, we combined known mucolytic agents to lower the viscosity of sputum and applied that to alpha and beta coronavirus, porcine epidemic diarrhea virus (PEDV) and Middle East respiratory syndrome coronavirus (MERS-CoV), respectively, spiked in sputum to find optimal pretreatment conditions. The pretreatment method using tris(2-carboxyethyl)phosphine (TCEP) and BSA was suitable for ICA diagnosis of sputum samples spiked with PEDV and MERS-CoV. This sensitive assay for the detection of coronavirus in sputum provides an useful information for the diagnosis of pathogen in low respiratory tract.

• IMMUNE NETWORK
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• v.14 no.4
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• pp.187-200
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• 2014

Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) are the most common cause of genital ulceration in humans worldwide. Typically, HSV-1 and 2 infections via mucosal route result in a lifelong latent infection after peripheral replication in mucosal tissues, thereby providing potential transmission to neighbor hosts in response to reactivation. To break the transmission cycle, immunoprophylactics and therapeutic strategies must be focused on prevention of infection or reduction of infectivity at mucosal sites. Currently, our understanding of the immune responses against mucosal infection of HSV remains intricate and involves a balance between innate signaling pathways and the adaptive immune responses. Numerous studies have demonstrated that HSV mucosal infection induces type I interferons (IFN) via recognition of Toll-like receptors (TLRs) and activates multiple immune cell populations, including NK cells, conventional dendritic cells (DCs), and plasmacytoid DCs. This innate immune response is required not only for the early control of viral replication at mucosal sites, but also for establishing adaptive immune responses against HSV antigens. Although the contribution of humoral immune response is controversial, $CD4^+$ Th1 T cells producing IFN-${\gamma}$ are believed to play an important role in eradicating virus from the hosts. In addition, the recent experimental successes of immunoprophylactic and therapeutic compounds that enhance resistance and/or reduce viral burden at mucosal sites have accumulated. This review focuses on attempts to modulate innate and adaptive immunity against HSV mucosal infection for the development of prophylactic and therapeutic strategies. Notably, cells involved in innate immune regulations appear to shape adaptive immune responses. Thus, we summarized the current evidence of various immune mediators in response to mucosal HSV infection, focusing on the importance of innate immune responses.

• Journal of Sericultural and Entomological Science
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• v.34 no.1
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• pp.35-40
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• 1992

An enzyme-linked immunosorbent assay (ELISA) was studied for the rapid diagnosis of the flacherie virus (FV) of the silkworm, Bombyx mori. The optimised concentration of rabbit anti-FV IgG and enzyme conjugate for the this technique were 15$\mu\textrm{g}$/$m\ell$ and 1:100 dilution, respectively. In ELISA, the detectable concentation of purified FV was 15ng/$m\ell$, and the flacherie viral antigens in the larval extracts were detected as early as 24 hours after the experimental infection. The results indicated that ELISA technique proved to be applicable for the rapid diagnosis of flacherie virus disease.

• Korean Journal of Veterinary Research
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• v.30 no.4
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• pp.435-440
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• 1990

Ten pigs infected with Aujeszky's disease virus (ADY) or hog cholera virus(HCV) were tested for the detection of virus antigens in frozens or paraffin-embedded sections by avidin-biotin-peroxidase complex(ABC) method. Tonsils, spleens, cerebra and buffy coats were examined for the immunohistochemical test. Where ADV antigen was detected by ABC, a dark brown deposit occurred in both the nucleus and the cytoplasm of lymphocytes and macrophages, however, HCV antigen was demonstrated in the cytoplasm of the infected cells. ADV-positive cells were most frequently detected in tonsils and cerebra, whereas, HCV -positive cells were frequently observed in spleens. And buffy coat were also good for both virus detection. The results suggested that ABC method is considered as an excellent and reliable tool for confirmative diagnosis of these viral diseases.

• Korean Journal of Veterinary Research
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• v.61 no.2
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• pp.19.1-19.7
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• 2021

Feline panleukopenia virus (FPV) causes leukopenia and severe hemorrhagic diarrhea, killing 50% of naturally infected cats. Although intact FPV can serve as an antigen in the hemagglutination inhibition (HI) test, an accidental laboratory-mediated infection is concern. A non-infectious diagnostic reagent is required for the HI test. Here, we expressed the viral protein 2 (VP2) gene of the FPV strain currently prevalent in South Korea in a baculovirus expression system; VP2 protein was identified by an indirect immunofluorescence assay, electron microscopy (EM), Western blotting (WB), and a hemagglutination assay (HA). EM showed that the recombinant VP2 protein self-assembled to form virus-like particles. WB revealed that the recombinant VP2 was 65 kDa in size. The HA activity of the recombinant VP2 protein was very high at 1:2¹⁵. A total of 143 cat serum samples were tested using FPV (HI-FPV test) and the recombinant VP2 protein (HI-VP2 test) as HI antigens. The sensitivity, specificity, and accuracy of the HI-VP2 test were 99.3%, 88.9%, and 99.3%, respectively, compared to the HI-FPV test. The HI-VP2 and HI-FPV results correlated significantly (r = 0.978). Thus, recombinant VP2 can substitute for intact FPV as the serological diagnostic reagent of the HI test for FPV.

• Korean Journal of Veterinary Service
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• v.45 no.2
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• pp.133-137
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• 2022

Lumpy skin disease (LSD) is a severe cross-border infectious disease that causes fever, skin and visceral nodules in cattle. LSD is caused by the lumpy skin disease virus (LSDV), a dsDNA virus that belongs to the genus Capripoxvirus. Although LSD has been found only in Southern Africa traditionally, in the last decade it is spreading very quickly through the Middle East and into Eastern Europe and China. It usually affects cattle and water buffalos being transmitted by blood-feeding insects. As it causes a huge economic impact, LSD is a notifiable disease by World Organisation for Animal Health, and managed as the legal infectious disease class I in Korea. Therefore, the purpose of this study was to confirm the existence of LSDV antigens or antibodies in Korean livestock. We collected 1,200 blood samples from cattle (Korean native and dairy cattle) and Korean water deer in 4 major provinces of the country, then tested the existence of LSDV antigen and antibody. None (0.0%) of the 1,200 blood samples were positive for both antigen and antibody of LSDV. To the best of our knowledge, this is the first study that examines the prevalence of LSDV in Korea. Our study aims to report the LSDV occurrence situation obtained by surveillance in Korea and provide information that may help prevention of LSD epidemics.