• Biomolecules & Therapeutics
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• 제31권3호
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• pp.350-358
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• 2023

Hand-foot-and-mouth disease (HFMD) is a viral infectious disease that occurs in children under 5 years of age. Its main causes are coxsackievirus (CV) and enterovirus (EV). Since there are no efficient therapeutics for HFMD, vaccines are effective in preventing the disease. To develop broad coverage against CV and EV, the development of a bivalent vaccine form is needed. The Mongolian gerbil is an efficient and suitable animal model of EV71 C4a and CVA16 infection used to investigate vaccine efficacy following direct immunization. In this study, Mongolian gerbils were immunized with a bivalent inactivated EV71 C4a and inactivated CVA16 vaccine to test their effectiveness against viral infection. Bivalent vaccine immunization resulted in increased Ag-specific IgG antibody production; specifically, EV71 C4a-specific IgG was increased with medium and high doses and CVA16-specific IgG was increased with all doses of immunization. When gene expression of T cell-biased cytokines was analysed, Th1, Th2, and Th17 responses were found to be highly activated in the high-dose immunization group. Moreover, bivalent vaccine immunization mitigated paralytic signs and increased the survival rate following lethal viral challenges. When the viral RNA content was determined from various organs, all three doses of bivalent vaccine immunization were found to significantly decrease viral amplification. Upon histologic examination, EV71 C4a and CVA16 induced tissue damage to the heart and muscle. However, bivalent vaccine immunization alleviated this in a dose-dependent manner. These results suggest that the bivalent inactivated EV71 C4a/CVA16 vaccine could be a safe and effective candidate HFMD vaccine.

• Asian Pacific Journal of Cancer Prevention
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• 제15권13호
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• pp.5469-5474
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• 2014

Background: This study aimed to examine the level of knowledge, attitude, acceptance, and willingness to pay (WTP) for HPV vaccination among female parents of girls aged 12-15 years in Thailand. Materials and Methods: A cross-sectional survey was conducted in eight schools across Bangkok. Results: Of 1,200 questionnaires sent out, a total of 861 questionnaires were received. Knowledge regarding the HPV vaccine among parents was quite low. Only half of the parents knew about the link between HPV and cervical cancer while one-third of them knew that the vaccine should be administered to the children before they become sexually active. Nevertheless, vaccine acceptance was high if it was offered for free: 76.9% for the bivalent and 74.4% for the quadrivalent vaccine. The proportion of respondents who were willing to copay for the vaccine if it was not totally free was also high, ranging from 68.9% for the bivalent to 67.3% for the quadrivalent vaccine. No significant difference between bivalent and quadrivalent vaccines in terms of prevalence of acceptance and willingness to pay was found. About one-third of the participants, who were willing to copay for the vaccine if it was not offered for free, indicated that they would copay less than 500 baht (30 baht = approx US$1) for three doses of bivalent vaccine. Conclusions: Substantial effort should be made to educate parents prior to introduction of a national HPV vaccination program. In terms of acceptance, either bivalent or quadrivalent vaccines can be recommended.

• IMMUNE NETWORK
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• 제23권6호
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• pp.43.1-43.10
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• 2023

The continuous emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants has provided insights for updating current coronavirus disease 2019 (COVID-19) vaccines. We examined the neutralizing activity of Abs induced by a BA.4/5-containing bivalent mRNA vaccine against Omicron subvariants BN.1 and XBB.1.5. We recruited 40 individuals who had received a monovalent COVID-19 booster dose after a primary series of COVID-19 vaccinations and will be vaccinated with a BA.4/5-containing bivalent vaccine. Sera were collected before vaccination, one month after, and three months after a bivalent booster. Neutralizing Ab (nAb) titers were measured against ancestral SARS-CoV-2 and Omicron subvariants BA.5, BN.1, and XBB.1.5. BA.4/5-containing bivalent vaccination significantly boosted nAb levels against both ancestral SARS-CoV-2 and Omicron subvariants. Participants with a history of SARS-CoV-2 infection had higher nAb titers against all examined strains than the infection-naïve group. NAb titers against BN.1 and XBB.1.5 were lower than those against the ancestral SARS-CoV-2 and BA.5 strains. These results suggest that COVID-19 vaccinations specifically targeting emerging Omicron subvariants, such as XBB.1.5, may be required to ensure better protection against SARS-CoV-2 infection, especially in high-risk groups.

• 대한수의학회지
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• 제53권1호
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• pp.43-48
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• 2013

Commercial bivalent killed Salmonella vaccine Salenvac-T has been used in several countries in order to prevent salmonellosis with Salmonella enterica serovars Enteritidis (SE) and Typhimurium (ST) in poultry. However, this vaccine has not been used in poultry farms in South Korea. In this study, we evaluated the efficacy of Salenvac-T vaccine to protect against the challenge of virulent SE and ST, and the effect of the vaccine on egg production and mortality in layer hens. The colonization of liver, spleen and cecum with challenged SE and ST was reduced in vaccinated chickens compared with that of unvaccinated control group. The twice vaccination with Salenvac-T induced elevated antibody responses against both SE and ST detected by enzyme-linked immunosorbent assay (ELISA). The higher average hen-day production was observed in the vaccinated layer hens than in the unvaccinated layer hens without significance. The average mortality was lower in the vaccinated layer hens during the experiment period. The antibody responses to both SE and ST were persistently detected in the vaccinated layers. In summary, vaccination with Salenvac-T reduces colonization of internal organs and induces good antibody responses, thereby results in higher performance and lower egg contamination with SE and ST in layer hens.

• Journal of Veterinary Science
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• 제23권3호
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• pp.49.1-49.13
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• 2022

Background: Porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae (MHP) are economically significant pathogens in the pig industry. The use of combined vaccines against PCV2 and MHP is one of the most effective ways of protecting pigs from both diseases, and it has become a part of general management. Objectives: This study evaluated the efficacy of two new bivalent vaccines of PCV2 and MHP (Myco-X and Myco-XD) in SPF pigs. Myco-X and Myco-XD are a combined vaccine of MHP with PCV2b and PCV2d, respectively. Methods: Sixteen pigs were divided into four groups: Myco-X-vaccinated challenged, Myco-XD-vaccinated challenged, unvaccinated challenged, and unvaccinated unchallenged. Two milliliters of Myco-X were administered intramuscularly, and 0.5 mL of Myco-XD was injected intradermally at 3 wk of age. The pigs were challenged with virulent PCV2d via the intramuscular and intranasal route 4 wk post-vaccination. Results: All vaccinated pigs showed effective reduction of the clinical signs, the PCV2d load in the blood and nasal swab samples, as well as lung and lymphoid tissue lesions in the challenge test. Compared to unvaccinated challenged animals, the vaccinated challenged animals showed significantly higher (p < 0.05) levels of anti-PCV2 IgG, PCV2d-specific interferon-γ (IFN-γ), and anti-MHP IgG. Conclusions: Based on clinical, microbiological, serological, and pathological assessments, this study confirmed that both combined vaccines could protect pigs against PCV2 infection caused by PCV2d. On the other hand, further research on the efficacy evaluation of these new vaccines against the MHP challenge and PCV2d/MHP co-challenge is needed.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2009년도 International Meeting of the Microbiological Society of Korea
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• pp.72-73
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• 2009

• Journal of Animal Science and Technology
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• 제64권3호
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• pp.588-598
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• 2022

Despite vaccination, equine influenza virus (EIV) and equine herpesvirus (EHV) infections still cause highly contagious respiratory diseases in horses. Recently, concurrent vaccination with EIV and EHV was suggested as a new approach; however, there have been no reports of concurrent vaccination with recombinant canarypox EIV and inactivated EHV vaccines. In this study, we aimed to compare the EIV-specific immune responses induced by concurrent administrations of a recombinant canarypox EIV vaccine and an inactivated bivalent EHV vaccine with those induced by a single recombinant canarypox EIV vaccine in experimental horse and mouse models. Serum and peripheral blood mononuclear cells (PBMCs) were collected from immunized animals after vaccination. EIV-specific serum antibody levels, serum hemagglutinin inhibition (HI) titers, and interferon-gamma (IFN-γ) levels were measured by enzyme-linked immunosorbent assay, HI assay, and quantitative polymerase chain reaction, respectively. Concurrent EIV and EHV vaccine administration significantly increased IFN-γ production, without compromising humoral responses. Our data demonstrate that concurrent vaccination with EIV and EHV vaccines can enhance EIV-specific cellular responses in horses.

• Asian Pacific Journal of Cancer Prevention
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• 제16권12호
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• pp.4895-4900
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• 2015

Physician recommendation is an important predictor of HPV vaccine acceptance; however, physician willingness and preferences regarding HPV vaccination may be influenced by factors including patient age, vaccine type, and cost. A cross-sectional survey was administered to a convenience sample of health care providers in Da Nang, Vietnam, to evaluate awareness, perceptions about HPV and HPV vaccines, and willingness to vaccinate a female patient. Willingness to vaccinate was evaluated using a full-factorial presentation of scenarios featuring the following factors: vaccine cost (free vs 1,000,000 VND), patient age (12, 16, or 22 years), and HPV vaccine type (bivalent vs quadrivalent). Responses from 244 providers were analyzed; providers had a mean age of $34{\pm}11.9$ years; a majority were female, married, and had children of their own. Thirty-six percent specialized in obstetrics/gynecology and 24% were providers in family medicine. Of the three factors considered in conjoint analysis, vaccine cost was the most important factor in willingness to vaccinate, followed by patient age, and vaccine type. The most favorable scenario for vaccinating a female patient was when the vaccine was free, the patient was 22 years of age, and the HPV4 vaccine was described. In multivariable analysis, older age, being a physician, being married, and having children were all associated with increased willingness to recommend HPV vaccination (p<0.05). Provider willingness is an important aspect of successful HPV vaccination programs; identifying preferences and biases in recommendation patterns will highlight potential areas for education and intervention.

• Archives of Pharmacal Research
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• 제29권11호
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• pp.1042-1048
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• 2006

Plasmid DNA vaccines encoding the hepatitis B virus (HBV) surface and hepatitis C virus (HCV) envelope antigens, respectively, were constructed, and attempt were made to find the possibility of a divalent vaccine against HBV and HCV. The expression of each plasmid in Cos-1 cells was confirmed using immunocytochemistry. To measure the induced immune response by these plasmids in vivo, female BALB/c mice were immunized intramuscularly with $100\;{\mu}g$ of either both or just one of the plasmids. Anti-HBV and HCV-specific antibodies and related cytokines were evaluated to investigate the generation of both humoral and cellular immune responses. As a result, specific anti-HBV and anti-HCV serum antibodies from mice immunized with these plasmids were observed using immunoblot. The levels of IL-2 and RANTES showing a $Th_{1}$ immune response were significantly increased, but there was no change in the level of IL-4 ($Th_{1}$ immune response) in any of the immunized groups. Compared with each plasmid DNA vaccine, the combined vaccine elicited similar immune responses in both humoral and cell-mediated immunities. These results suggest that the combined DNA vaccine can induce not only comparable immunity experimentally without antigenic interference, but also humoral and $Th_{1}$ dominant cellular immune responses. Therefore, they could serve as candidates for a simultaneous bivalent vaccine against HBV and HCV infections.

• 한국가금학회지
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• 제34권4호
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• pp.301-318
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• 2007

Marek's disease (MD) is a highly contagious lymphoproliferative disease of poultry caused by the oncogenic herpesvirus designated Marek's disease virus (MDV). MD has a worldwide distribution and is thought to cause an annual loss over US$ one billion to the poultry industry. Originally described as a paralytic disease, today MD is mostly manifested as an acute disease with tumors in multiple visceral organs. MD is controlled essentially by the widespread use of live vaccines administered either in ovo into 18-day-old embryos or into chicks immediately after they hatch. In spite of the success of the vaccines in reducing the losses from the disease in the last 30 years, MDV strains have shown continuous evolution in virulence acquiring the ability to overcome the immune responses induced by the vaccines. During this period, different generations of MD vaccines have been introduced to protect birds from the increasingly virulent MDV strains. However, the virus will be countered each new vaccine strategy with ever more virulent strains. In spite of this concern, currently field problem from MD is likely to be controled by strategy of using bivalent vaccine. But, potential risk factors for outbreak of MD are still remained in this condition. The major factors can be thought that improper handling and incorrect administration of the vaccine, infection prior to establishment of immunity, suppression of immune system by environmental stress and outbreaks of more virulent MDV strain by using vaccine and genetic resistance of host.