• Title/Summary/Keyword: Live Vaccines

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Polymeric Microspheres As Antigen Delivery Systems

  • Oh, Yu-Kyoung
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.11a
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    • pp.115-120
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    • 1996
  • Vaccination has been considered to be the most effective way to control infectious diseases. Currently, many vaccines used in humans are live-attenuated or killed microorganisms. Polio, mumps, and measles vaccines are live-attenuated. Killed vaccines include cholera and pertussis vaccines, These conventional vaccines, however, suffer from some problems. In the case of live-attenuated vaccines, reversion to virulence is observed in a small but significant number of clinical cases each year. In killed vaccines, due to the possible hazard to employees working with live pathogens, the cost of preparation is high. Killed vaccines also need to be given in multiple doses, Furthermore, both live-attenuated and killed vaccines have possible presence of cellular materials leading to side effects. Moreover, there are diseases such as malaria and hepatitis for which conventional attenuated and killed vaccines are not available because the pathogens cannot be grown in sufficient amounts to allow the classical methods to be used.

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Recent Progress in Development of Vaccines against Avian Coccidiosis (조류 콕시듐증의 백신개발에 대한 최근의 진보)

  • Lillehoj, Hyun S.
    • Korean Journal of Poultry Science
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    • v.26 no.3
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    • pp.149-170
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    • 1999
  • Protozoa of the genus Eimeria are the etiologic agents of avian coccidiosis, the most economically important Parasitic disease for the poultry industry. Coccidia multiply in intestinal epithelial cells of a wide range of hosts, including livestock in addition to poultry. Chemotherapy is extensively used to control coccidiosis. However, development of drug resistance by Eimeria parasites, the intensive cost and labor involved in the identification of new anticoccidial compounds and public awareness of drug residues in foods warrant alternative methods to prevent coccidiocic in the fast growing poultry industry. For these reasons, there is a great interest in developing vaccines against avian coccidiosis. Live Eimeria vaccines confer protective immunity, however a significant disadvantage of using these types of vaccines is their pathogenicity. Live parasites with attenuated pathogenicity also usually produce immunity but may revert back to a pathogenic form and may be contaminated with other pathogenic organisms. Killed Eimeria vaccines are safer but, unlike live attenuated vaccines, are not able to generate cytotoxic T lymphocyte responses. Recombinant vaccines are biochemically purified proteins produced by genetic engineering that consist of particular epitopes or metabolites of Eimeria. Unlike live attenuated organisms, recombinant vaccines do not possess as much risk and generally are able to induce both humoral and cell mediated immunity. DNA vaccines consist of genes encoding immunogenic proteins of pathogens that are directly administered into the host in a manner that the gene is expressed and the resulting protein generates a protective immune response. Although all of these different types of vaccines have been applied to coccidiosis, this disease continues to cause substantial morbidity and mortality in the poultry industry. Future development of an effective vaccine against coccidiosis will depend on further investigation of protective immunity to Eimeria infection and identification of important immundgenic parasite molecules.

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Reappraisal of Live Vaccines and Immunity in These Modern Days (현대에서의 생백신과 이에 대한 면역반응의 재평가)

  • Kim, Kyung Hyo
    • Pediatric Infection and Vaccine
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    • v.16 no.1
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    • pp.24-30
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    • 2009
  • The vaccines has been developed over the first two hundred years since Jenner's smallpox vaccination. In modern days, vaccination has had the largest impact on the incidence and persistence of infections. Although natural infection induces lifelong immunity, the assumption that the vaccine also confers permanent protection has been reconsidered following outbreaks of measles in students who had been vaccinated 15-20 years prior to infection in the US in the 1980s. Clinical studies have proposed several mechanisms such as vaccine failure in some individuals and the subsequent loss of immunity after vaccination. An ideal vaccine is relatively easy to define, but few real vaccines approach the ideal. Many difficulties account for the failure in producing these ideal vaccines. However, recent advances in methods for studying immune response to pathogens have provided a better understanding of immune mechanisms. Based on these findings, the development of good vaccine formulations allowing stimulation of optimal and prolonged protective immunity and immunization policies or schedules should lead to the introduction of vaccines for previously resistant organisms.

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Efficacy of Concurrent Administration of Live and Killed Newcastle Disease Vaccines in Day - Old Broiler Chicks (육용계 초생추에 대한 뉴켓슬병 생독 및 사독 백신의 동시접종 효과)

  • 최정옥;박승주;위성하
    • Korean Journal of Poultry Science
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    • v.15 no.3
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    • pp.193-198
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    • 1988
  • In order to examine the efficacy of concurrent vaccination with live and killed Newcastle disease(ND) vaccines two types of each live($B_1$ and LaSota) and killed(gel and oil) vaccines of all commercial origin were administered either alone or simultaneously to day-old broiler chicks having maternal antibody. Live vaccines were given by conjuntival instillation in volumes of 25${\mu}\ell$ containing $10^{6.0}$ to $10^{6.3}$ median embroy infective dose(EH)) while killed vaccines were given in 0.3$m\ell$ volumes subcutaneously at the back of the neck Hemagglutination inhibition(HI) antibodies were determined at weekly intervals until 8 weeks of age and protection rate was determined at 4 and 8 week of age by challenge inoculation with virulent ND virus(NDV). During the 8 weeks experimental period concurrent administration of live and oil vaccine produced the highest level of HI antibody and the most satisfactory protection, whereas concurrent rent vaccination with live and gel vaccine induced poor immune responses. There was no noticeable difference in the efficacy between the live vaccines, Bl and LaSota when simultaneously administered with oil vaccine. Except for oil vaccine, single administration of either live or killed vaccine at day-old produced less than 50% protection at 4 and 8 weeks postvaccination(PV). Oil vaucine alone induced 80% and 70% protection at 4 and 8 week PV, respectively. Concurrent vaccination caused on visible side reaction like respiratory symptoms and did not negatively influence the growth rate of birds until the end of experiment.

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Serological responses and protection levels in chickens administered with Newcastle disease vaccines

  • Geumji Seung;Jiye Kim;Hyobi Kim;Ji-Yeon Kim;Yang-Ho Jang;Yeon-Hee Kim;Moon Her;Seong-Joon Yi;Keun-Woo Lee;Il Jang;Young Ju Lee
    • Korean Journal of Veterinary Research
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    • v.62 no.4
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    • pp.29.1-29.7
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    • 2022
  • Vaccination against Newcastle disease (ND) is the most effective means of controlling the disease, and these vaccines are commercialized only after their safety and effectiveness have been verified through tests that comply with Korean Standards of National Lot Release for Veterinary Biologics. This study investigated whether a relatively convenient and safe serological test can be used in place of the challenge test using highly virulent ND virus. Hemagglutination inhibition (HI) assay and enzyme-linked immunosorbent assay (ELISA) were considered positive of log2 2 or more and cutoff value of 200 or more, respectively, in both live and inactivated vaccines. However, when the antibody levels of the live and inactivated vaccines induced using the Ulster 2C, KBNP-C4152R2L, and K148/08 strains were compared, the antibody titers for inactivated vaccines were significantly higher than those for live vaccines in both the HI assay and ELISA. A strong positive correlation was observed between HI and ELISA antibody titers. The live vaccines corresponded to a survival rates of ≥ 80% and the inactivated vaccines corresponded to 100% survival rates. This study confirmed that standard efficacy tests can serve as serological tests, and can replace the challenge test and that the vaccine approval process can be improved.

Development of Vaccine Delivery System and Challenges (백신 전달기술 개발 동향과 과제)

  • Jung, Hyung-Il;Kim, Jung-Dong;Kim, Mi-Roo;Dangol, Manita
    • KSBB Journal
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    • v.25 no.6
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    • pp.497-506
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    • 2010
  • Vaccine is a protective clinical measure capable of persuading immune system against infectious agents. Vaccine can be categorized as live attenuated and inactivated. Live attenuated vaccines activate immunity similar to natural infection by replicating living organisms whereas inactivated vaccines are either whole cell vaccines, eliciting immune response by killed organisms,or subunit vaccines, stimulating immunity by non-replicating sub cellular parts. The components of vaccine play a critical role in deciding the immune response mediated by the vaccine. The innate immune responds against the antigen component. Adjuvants represent an importantcomponent of vaccine for enhancing the immunogenicity of the antigens. Subunit vaccines with isolated fractions of killed and recombinant antigens are mostly co-administered with adjuvants. The delivery system of the vaccine is another essential component to ensurethat vaccine is delivered to the right target with right dosage form. Furthermore, vaccine delivery system ensures that the desired immune response is achieved by manipulating the optimal interaction of vaccine and adjuvantwith the immune cell. The aforementioned components along with routes of administration of vaccine are the key elements of a successful vaccination procedure. Vaccines can be administered either orally or by parenteral routes. Many groups had made remarkable efforts for the development of new vaccine and delivery system. The emergence of new vaccine delivery system may lead to pursue the immunization goals with better clinical practices.

Recombinant zoster vaccine (Shingrix®): a new option for the prevention of herpes zoster and postherpetic neuralgia

  • Singh, Grisuna;Song, Sejin;Choi, Eunjoo;Lee, Pyung-Bok;Nahm, Francis Sahngun
    • The Korean Journal of Pain
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    • v.33 no.3
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    • pp.201-207
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    • 2020
  • Postherpetic neuralgia (PHN) is a challenging condition for pain management specialists. The prevention of herpes zoster (HZ) and subsequent PHN in individuals aged 50 years and older, via the development of new vaccines, is an ongoing research project. The live zoster vaccine (LZV, Zostavax®) was the first proof of concept that vaccination could prevent HZ, but LZV cannot be used in various immunecompromised patients. This led to the development of a new non-live recombinant zoster vaccine (RZV, Shingrix®). This RZV has shown promising results in many clinical trials, with high reactogenicity and similar systemic adverse effects compared to those of LZV. The National Advisory Committee on Immunization has recommended LZV as a standard vaccine for HZ prevention in adults ≥ 50 years of age, but no studies directly comparing the safety and efficacy of RZV and LZV vaccines have been conducted. This article reviews the brief history, efficacy, and safety of the two vaccines and discusses the advantage of RZV over LZV based on the available literature.

Rotavirus Vaccines (로타바이러스 백신)

  • Koh, Hong
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.12 no.sup1
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    • pp.72-76
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    • 2009
  • Rotavirus infection is the leading cause of severe diarrhea disease in infants and young children worldwide. Rotavirus infects every child at least once by her/his $5^{th}$ birthday. It has been known that single episode of rotavirus infection can protect or alleviate subsequent illness caused by both homotypic and heterotypic rotaviruses. There are two currently licensed rotavirus vaccines. One is human-bovine rotavirus reassortant pentavalent vaccine ($RotaTeq^{TM}$), which contains five reassortant rotavirus (expressing protein G1, G2, G3, G4 and P[8]) and was licensed in Korea for use among infants in 2007. Another is live-attenuated human rotavirus vaccine ($Rotarix^{TM}$) derived from 89-12 strain which represents the most common of the human rotavirus VP7(G1) and VP4(P[8]) antigens. $Rotarix^{TM}$ was licensed in Korea in 2008. Both live oral rotavirus vaccines are efficacious in preventing severe rotavirus gastroenteritis.

Effect of autogenous Escherichia coli vaccine in pig (돼지에서 대장균 자가백신 효과)

  • 윤교복;김종술;정동수;박양주;이유섭;한정희
    • Korean Journal of Veterinary Service
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    • v.21 no.2
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    • pp.117-126
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    • 1998
  • This study was performed to investigate the immunogenicity of autogenous E coli vaccines and their preventive effects on diarrhea in suckling piglets. Autogenous E coli live and killed vaccines were made from the E coli strains isolated from piglets showing diarrhea in field. In group I, pregnant sows were administered with live and killed vaccines at 4 and 2 weeks before parturition, respectively, Killed vaccines were administered twice to pregnant sows at 4 and 2 weeks before parturition in group II, and saline instead of autogenous E coli vaccines was administered to pregnant sows in group III for the control. After parturition, antibody titers in colostrum and milk from sows, incidence of diarrhea in suckling piglets, and immunoreactivity in the ileum of piglets from each treatment group were examined. The results were as follows ; 1. Sixty-two strains of E coli were isolated from suckling piglets with diarrhea. Of the strains, K88 pilus and K99 pilus antigens were identified in 6(9.8%) and 4(6.5%), respectively. Molecular weights of K88 and K99 pilus were 27,500 and 18,500 daltons, respectively. 2. Antibody titers in colostrum from sows after parturition were 1 : 512 to 1 : 1,024 in group I, 1.256 to 1.512 in group II, and 1 : 4 to 1 : 16 in group III. 3. The incidences of diarrhea In suckling piglets of group I, II and III were 3.3%, 9.4% and 21.4%, respectively. 4. When the immunoreactivity in the ileum of piglets from each group was examined, the proportion of IgG-immunoreactivity cells in group I or II was higher than that in group III. In conclusion, administration of autogenous E coli vaccines to pregnant sows before parturition can be an effective way to prevent diarrhea in suckling piglets.

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Safety and efficacy of modified-live infectious laryngotracheitis vaccines (닭 전염성 후두기관염 생독백신의 안전성과 효능)

  • Han, Myung-Guk;Lee, O-Soo;Kim, Jea-Hong
    • Korean Journal of Veterinary Research
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    • v.42 no.2
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    • pp.241-251
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    • 2002
  • Modified-live (ML) infectious laryngotracheitis (ILT) vaccines have been widely used as a preventive measure in Korea since the first outbreak of ITL. Recently, it has been observed that chickens vaccinated with the commercially available ML ILT vaccine have sometimes exhibited adverse clinical signs. In this study, we evaluated the quality of the vaccines by comparing titer of each vaccine batch and testing the stability of ILT virus (ILTV) in vaccine diluents and compared the safety and efficacy of vaccines in specific pathogen free (SPF) chickens. The ratio of maximum titer to minimum titer of vaccine produced by most manufacturers was 2 to 15. However, 2 out of 11 manufacturers produced vaccines of which the ratio was 74 to 478. Most vaccines examined were maintained vaccine titers suitable for national regulations within expiry date. However, some vaccines did not keep the titer required for the national regulations. In the test for stability of ILTV in various diluents, ILTV was highly stable in lactose-phosphate-glutamine-gelatin solution, sucrose-phophate-glutamine-albumin solution and some vaccine diluents produced by manufacturers. The safety of ML ILT vaccines was assessed in 10-day-old SPF chicks. Mortality in SPF chicks inoculated intratracheally with one dose of vaccine varied depending on vaccines and some vaccines produced 50-85% mortality. Seven-week-old SPF chickens were vaccinated intraocularly with ML ILT vaccines and then challenged intratracheally with ILT challenge virus 14 days after vaccination. The protection rate was assessed by clinical signs and reisolation of the ILT challenge virus from tracheas taken at day 4 after challenge. There were slight respiratory reactions in some vaccinated chickens after vaccination but these reactions disappeared within 5 days after vaccination. No further clinical signs and death were observed. Protection rate determined by clinical signs and mortality was 100% in all vaccinated groups. However, the challenge virus was isolated from all tracheas of chickens vaccinated with vaccine B or control groups. The challenge virus was also isolated in the trachea of one in five chickens vaccinated with either vaccine F or K, but not in tracheas of chickens vaccinated with other vaccines. In the present study, the stability of vaccine diluents, pathogenicity and protection rate based on reisolation test of the challenge virus were different depending on vaccines produced by eleven manufacturers.