• Title/Summary/Keyword: vaccine efficacy

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Evaluation of Factors that Can Affect Protective Immune Responses Following Oral Immunization of Recombinant Helicobacter pylori Urease Apoenzyme

  • Kim, Jang-Seoung;Chang, Ji-Hoon;Park, Eun-Jeong;Chung, Soo-Il;Yum, Jung-Sun
    • Journal of Microbiology and Biotechnology
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    • v.10 no.6
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    • pp.865-872
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    • 2000
  • Helocobacter phylori is the major cause of gastritis, peptic ulcer, and a principal risk factor for gastric cancer. As the firs step towards a vaccine against H. pylori infection, Hy.pylori urease was expressed and purified as a recombinant apoenzyme (rUrease) in E. coli. In order to develop an effective immunization protocol using rUrease, the host immune responses were evaluated after the oral immunization of mice with rUrease preparations plus cholera toxin relative to various conditions, such as the physical nature of the antigen, the frequency of the booster immunization, the dose of the antigen, and the route of administration. The protective efficacy was assessed using a quantitative culture following an H. pylori SS1 challenge. It was demonstrated that rUrease, due to its particulated nature, was more superior than the UreB subunit as a vaccine antigen. The oral immunization of rUrease elicited significant systemic and secretory antibody responses, and activated predominantly Th2-type cellular responses. The bacterial colonization was significantly reduced (~100-fold) in those mice immunized with three or four weekly oran doses of rUrease plus cholera toxin (p<0.05), when compared to the non-immunized/challenged controls. The protection correlated well with the elicited secretory IgA level against rUrease, and these secretory antibody responses were highly dependent on the frequency of the booster immunization, yet unaffected by the dose of the antigen (25-200$\mu\textrm{g}$). These results demonstrate the remarkable potential of rUrease as a vaccine antigen, thereby strengthening the possibility of developing an H. pylori vaccine for humans.

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The protective efficacy of the enterotoxigenic Escherichia coli vaccine candidate by GI24 against neonatal piglet colibacillosis

  • Choi, Yeong Hwan;Moon, Ja Young;Seo, Byoung Joo;Kim, Won Kyung;Cho, Jeong Sang;Choi, Min Su;Lim, Jae Sam;Kim, Sung Bok;Kim, Won Il;Hur, Jin
    • Korean Journal of Veterinary Service
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    • v.40 no.4
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    • pp.235-244
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    • 2017
  • Enterotoxigenic Escherichia coli (ETEC) strains producing each F4, F5, F6 and F41 fimbriae were lysed by GI24 peptide. The lysate cells were used as ETEC vaccine candidate. This study was carried out to examine whether intramuscular (im) immunization of pregnant sows with the novel vaccine candidate could effectively protect their neonatal piglets against ETEC colibacillosis. All pregnant sows were primed at 11 weeks and were boosted at 14 weeks of pregnancy. Group A sows were im inoculated with PBS. Group B sows were im immunized with $2{\times}10^9$ the mixture. Seral IgG, colostral IgA and IgG titers from group B sows, and seral IgG and IgA levels in group B piglets were significantly higher than those of group A sows and piglets, respectively. After challenge with wild-type ETEC, diarrhea and mortality was not observed in group B piglets. However, diarrhea was observed in 66.7% of group A piglets, and 33.3% mortality was observed. These findings indicate that im immunization of sows with the mixture of the novel vaccine candidate can effectively protect their offspring from ETEC colibacillosis.

Development of an attenuated vaccine strain from a korean respiratory type infectious bronchitis virus (한국호흡기형 닭전염성기관지염 생독백신주의 작성)

  • Choi, Kang-Seuk;Jeon, Woo-Jin;Lee, Eun-Kyoung;Kye, Soo-Jeong;Park, Mi-Ja;Kwon, Jun-Hun
    • Korean Journal of Veterinary Research
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    • v.51 no.3
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    • pp.193-201
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    • 2011
  • An attenuated vaccine strain AVR1/08 of Korean respiratory type of infectious bronchitis virus (IBV) was developed by 89th passages of IBV D85/06 strain in chicken eggs. The AVR1/08 strain had higher virus titer at least 20 times ($10^{1.3}$) than the parent virus D85/06 by egg inoculation method. The AVR1/08 strain had a single point mutation (S to Y) at position 56 of spike protein of IBV compared to parent virus IBV D85/06 strain. The mutation was observed consistently at viruses after 47th passage in chicken eggs. The AVR1/08 strain showed no virulence even after 6 passages in chickens and all chickens inoculated induced anti-IBV antibody 14 days after vaccination. The AVR1/08 strain had broad protective efficacy against QX type Korean nephropathogenic virus (Q43/06 strain), KM91 type Korean nephropathogenic virus (KM91 strain) and Korean respiratory virus (D85/06 strain). In contrast, Massachusetts (Mass) type attenuated vaccine strain H120 showed protection of 37.5 to 50% against these three viruses. Our results indicate that the AVR1/08 strain has potential as an attenuated vaccine effective in controlling IBVs circulating in Korea.

Cell-Based IL-15:IL-15Rα Secreting Vaccine as an Effective Therapy for CT26 Colon Cancer in Mice

  • Thi, Van Anh Do;Jeon, Hyung Min;Park, Sang Min;Lee, Hayyoung;Kim, Young Sang
    • Molecules and Cells
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    • v.42 no.12
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    • pp.869-883
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    • 2019
  • Interleukin (IL)-15 is an essential immune-modulator with high potential for use in cancer treatment. Natural IL-15 has a low biological potency because of its short half-life and difficulties in mass-production. IL-15Rα, a member of the IL-15 receptor complex, is famous for its high affinity to IL-15 and its ability to lengthen the half-life of IL-15. We have double-transfected IL-15 and its truncated receptor IL-15Rα into CT26 colon cancer cells to target them for intracellular assembly. The secreted IL-15:IL-15Rα complexes were confirmed in ELISA and Co-IP experiments. IL-15:IL-15Rα secreting clones showed a higher anti-tumor effect than IL-15 secreting clones. Furthermore, we also evaluated the vaccine and therapeutic efficacy of the whole cancer-cell vaccine using mitomycin C (MMC)-treated IL-15:IL-15Rα secreting CT26 clones. Three sets of experiments were evaluated; (1) therapeutics, (2) vaccination, and (3) long-term protection. Wild-type CT26-bearing mice treated with a single dose of MMC-inactivated secreted IL-15:IL-15Rα clones prolonged survival compared to the control group. Survival of MMC-inactivated IL-15:IL-15Rα clone-vaccinated mice (without any further adjuvant) exceeded up to 100%. This protection effect even lasted for at least three months after the immunization. Secreted IL-15:IL-15Rα clones challenging trigger anti-tumor response via CD4+ T, CD8+ T, and natural killer (NK) cell-dependent cytotoxicity. Our result suggested that cell-based vaccine secreting IL-15:IL-15Rα, may offer the new tools for immunotherapy to treat cancer.

Epidemiological Investigation of a Measles Outbreak in a Preschool in Incheon, Korea, 2006 (2006년 인천의 한 유치원에서 발생한 홍역 유행 역학조사)

  • So, Jae-Sung;Go, Un-Yeong;Lee, Dong-Han;Park, Koang-Suk;Lee, Jong-Koo
    • Journal of Preventive Medicine and Public Health
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    • v.41 no.3
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    • pp.153-158
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    • 2008
  • Objectives : This study describes a plan that was designed to prevent a measles outbreak that showed a changed outbreak pattern. This study is based on the epidemiological investigation of a measles outbreak in a preschool in Incheon, Korea, 2006. Methods : The subjects were 152 students at a preschool where a measles outbreak occurred. A questionnaire survey was conducted and serological testing for measles-specific IgM was preformed. Results : Of the fifteen confirmed, identified cases, eleven patients had been vaccinated with one dose, one patient had received two doses and three patients were unvaccinated. The three unvaccinated cases consisted of one 5-year-old child, one 3-year-old child and one 16-month-old infant. For the cases with one dose of the vaccination, there were 11 cases, which consisted of six 5-year-old children, two 4-year-old children, two 3-year-old children and one 2-year-old child. The case with two doses of the vaccination was one 4-year-old child. The attack rate of measles was 100% in the 0-dose group, 11.2% in the 1-dose group and 2.0% in the 2-dose group. The vaccine's efficacy was 88.8% in the 1-dose group and 98.0% in the 2-dose group. The vaccine effectiveness for the 2-dose group was higher than that of the 1-dose group. Conclusions : High coverage with a 2-dose vaccination should be maintained, and the vaccination should be given at the suitable time to prevent a measles outbreak with a changed outbreak pattern.

Evaluation of Efficacy of PoulShot® MG-F Vaccine against Mycoplasma gallisepticum Infection in the Layer Farms (PoulShot® MG-F 백신의 마이코플라즈마 감염증에 대한 산란계 농장에서의 야외 효능 평가)

  • Jeon, Eun-Ok;Woo, Chang-Gok;Won, Ho-Keun;Mo, In-Pil
    • Korean Journal of Poultry Science
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    • v.37 no.2
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    • pp.181-190
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    • 2010
  • Mycoplasma gallisepticum (MG) infection results in severe economic loss in the poultry industry. In the previous reports, F strain, one of the MG live vaccine strains, could protect the bird from field infection of MG strains. In this study, efficacy of PoulShot$^{(R)}$ MG-F vaccine againset mycoplasma gallisepticum infection was evaluated for filed application in commercial layers. Commercial layers from two different farms received with PoulShot$^{(R)}$ MG-F, MG-F live vaccine at 9~14 weeks of age. Serological immune response to MG vaccine, the persistency of MG vaccine strain in the upper respiratory tracts and egg production rate were evaluated in the vaccinated, contacted or nonvaccinated flocks. The serological response was first detected at 3 weeks after vaccination (WAV) and persisted for 31 WAV. The MG vaccine strains were also persisted for 31 WAV based on the reisolation and PCR detection. There was no difference between the vaccinated or non-vaccinated flocks in the egg production rate but in the abnormality rate of eggs. Based on the above results, we suggested that the PoulShot$^{(R)}$, MG-F live vaccine was fully immunogenic and had characteristics of long persistence in the upper respiratory trachea which will reduce economic loss caused by MG infection in the layer farms.

A Study of Multiple Compression for Malicious Code Execution and Concealment (악성코드 실행과 은닉을 위한 다중 압축 연구)

  • Yi, Jeong-Hoon;Park, Dea-Woo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.299-302
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    • 2010
  • Recently, the malicious code is not easily detectable in the vaccine for the virus, malicious code as a compressed file by modulation pattern is the tendency to delay. Among the many antivirus engines on the market a compressed file that can be modulated by malicious code, and test whether the pattern will need to know. We cover a multi-compressed files, malicious code modulated secreted by examining patterns of test engine is being detected is through a computer simulation. Analysis of secreted activities of malicious code and infect the host file tampering with the system driver files and registry, it gets registered is analyzed. this study will contribute hidden malicious code inspection and enhance vaccine efficacy in reducing the damage caused by malicious code.

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Vaccine Strategy That Enhances the Protective Efficacy of Systemic Immunization by Establishing Lung-Resident Memory CD8 T Cells Against Influenza Infection

  • Hyun-Jung Kong;Youngwon Choi;Eun-Ah Kim;Jun Chang
    • IMMUNE NETWORK
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    • v.23 no.4
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    • pp.32.1-32.15
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    • 2023
  • Most influenza vaccines currently in use target the highly variable hemagglutinin protein to induce neutralizing antibodies and therefore require yearly reformulation. T cell-based universal influenza vaccines focus on eliciting broadly cross-reactive T-cell responses, especially the tissue-resident memory T cell (TRM) population in the respiratory tract, providing superior protection to circulating memory T cells. This study demonstrated that intramuscular (i.m.) administration of the adenovirus-based vaccine expressing influenza virus nucleoprotein (rAd/NP) elicited weak CD8 TRM responses in the lungs and airways, and yielded poor protection against lethal influenza virus challenge. However, a novel "prime-and-deploy" strategy that combines i.m. vaccination of rAd/NP with subsequent intranasal administration of an empty adenovector induced strong NP-specific CD8+ TRM cells and provided complete protection against influenza virus challenge. Overall, our results demonstrate that this "prime-and-deploy" vaccination strategy is potentially applicable to the development of universal influenza vaccines.

Pre-existing Immunity to Endemic Human Coronaviruses Does Not Affect the Immune Response to SARS-CoV-2 Spike in a Murine Vaccination Model

  • Ahn Young Jeong;Pureum Lee;Moo-Seung Lee;Doo-Jin Kim
    • IMMUNE NETWORK
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    • v.23 no.2
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    • pp.19.1-19.10
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    • 2023
  • Endemic human coronaviruses (HCoVs) have been evidenced to be cross-reactive to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although a correlation exists between the immunological memory to HCoVs and coronavirus disease 2019 (COVID-19) severity, there is little experimental evidence for the effects of HCoV memory on the efficacy of COVID-19 vaccines. Here, we investigated the Ag-specific immune response to COVID-19 vaccines in the presence or absence of immunological memory against HCoV spike Ags in a mouse model. Pre-existing immunity against HCoV did not affect the COVID-19 vaccine-mediated humoral response with regard to Ag-specific total IgG and neutralizing Ab levels. The specific T cell response to the COVID-19 vaccine Ag was also unaltered, regardless of pre-exposure to HCoV spike Ags. Taken together, our data suggest that COVID-19 vaccines elicit comparable immunity regardless of immunological memory to spike of endemic HCoVs in a mouse model.

Transcutaneous antigen delivery system

  • Lee, Mi-Young;Shin, Meong-Cheol;Yang, Victor C.
    • BMB Reports
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    • v.46 no.1
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    • pp.17-24
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    • 2013
  • Transcutaneous immunization refers to the topical application of antigens onto the epidermis. Transcutaneous immunization targeting the Langerhans cells of the skin has received much attention due to its safe, needle-free, and noninvasive antigen delivery. The skin has important immunological functions with unique roles for antigen-presenting cells such as epidermal Langerhans cells and dermal dendritic cells. In recent years, novel vaccine delivery strategies have continually been developed; however, transcutaneous immunization has not yet been fully exploited due to the penetration barrier represented by the stratum corneum, which inhibits the transport of antigens and adjuvants. Herein we review recent achievements in transcutaneous immunization, focusing on the various strategies for the enhancement of antigen delivery and vaccination efficacy.