• Journal of Microbiology and Biotechnology
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• 제7권2호
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• pp.144-150
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• 1997

We developed a simple and efficient method to prepare a Pseudomonas vaccine of outer membrane (OM) proteins free from lipopolysaccharide (LPS). A three step purification process including extraction, ultrafiltration and ultracentrifugation effectively removed LPS from the OM protein fraction. Approximately 2 mg of the OM proteins was obtained from 1 g of wet cell. LPS contaminant in the vaccine preparation was less than 0.003% (w/w) of protein and protease activity was not detectable. To achieve a wide range of protection, OM proteins prepared from four attenuated P. aeruginosa strains were mixed in equal amounts and used as a vaccine, which elicited in rabbits a high titer of antibody reactive to all of the seven Fisher types. The antisera from the immunized rabbit had a strong reactivity to vaccine proteins larger than 25 kDa. In a burned mouse infection model, immunization with the vaccine significantly enhanced bacterial clearance in the Pseudomonas infected skin. The vaccination also provided mice an excellent protection against Pseudomonas infection (11, 16). Data on antigenicity, mutagenicity, acute, subacute toxicity and pharmacological tests confirmed the safety of the vaccine (1, 3, 10, 12, 17). These data demonstrate that this method can be applied to manufacture a bacterial vaccine of OM proteins with safety and prophylactic efficacy at a practical low cost.

• Parasites, Hosts and Diseases
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• 제61권3호
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• pp.231-239
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• 2023

Toxoplasma gondii is an intracellular parasitic organism affecting all warm-blooded vertebrates. Due to the unavailability of commercialized human T. gondii vaccine, many studies have been reported investigating the protective efficacy of pre-clinical T. gondii vaccines expressing diverse antigens. Careful antigen selection and implementing multifarious immunization strategies could enhance protection against toxoplasmosis in animal models. Although none of the available vaccines could remove the tissue-dwelling parasites from the host organism, findings from these pre-clinical toxoplasmosis vaccine studies highlighted their developmental potential and provided insights into rational vaccine design. We herein explored the progress of T. gondii vaccine development using DNA, protein subunit, and virus-like particle vaccine platforms. Specifically, we summarized the findings from the pre-clinical toxoplasmosis vaccine studies involving T. gondii challenge infection in mice published in the past 5 years.

• Clinical and Experimental Vaccine Research
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• 제13권1호
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• pp.21-27
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• 2024

Chronic infectious diseases refer to diseases that require a long period of time from onset to cure or death, the use of therapeutic vaccines has recently emerged to eradicate diseases. Currently, clinical research is underway to develop therapeutic vaccines for chronic infectious diseases based on various vaccine formulations, and the recent success of the messenger RNA vaccine platform and efforts to apply it to therapeutic vaccines are having a positive impact on conquering chronic infectious diseases. However, since research on the development of therapeutic vaccines is still relatively lacking compared to prophylactic vaccines, there is a need to focus more on the development of therapeutic vaccines to overcome threats to human health caused by chronic infectious diseases. In order to accelerate the development of therapeutic vaccines for chronic infectious diseases in the future, it is necessary to establish a clear concept of therapeutic vaccines suitable for the characteristics of each chronic infectious disease, as well as standardize vaccine effectiveness evaluation methods, secure standards/reference materials, and simplify the vaccine approval procedure.

• Journal of Microbiology and Biotechnology
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• 제19권1호
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• pp.108-112
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• 2009

A simplified method for the purification of cholera toxin was developed. The 569B strain of Vibrio cholerae, a recognized hyper-producer of cholera toxin, was propagated in a bioreactor under conditions that promote the production of the toxin. The toxin was separated from the bacterial cells using 0.2-${\mu}m$ crossflow microfiltration, the clarified toxin was passed through the membrane into the permeate, and the bacterial cells were retained in the retentate. The 0.2-${\mu}m$ permeate was then concentrated 3-fold and diafiltered against 10 mM phosphate buffer, pH 7.6, using 30-kDa crossflow ultrafiltration. The concentrated toxin was loaded onto a cation exchange column, the toxin was bound to the column, and most of the impurities were passed unimpeded through the column. The toxin was eluted with a salt gradient of phosphate buffer, pH 7.0, containing 1.0 M NaCl. The peak containing the toxin was assayed for cholera toxin and protein and the purity was determined to be 92%. The toxin peak had a low endotoxin level of $3.1\;EU/{\mu}g$ of toxin. The purified toxin was used to prepare antiserum against whole toxin, which was used in a $G_{M1}$ ganglioside-binding ELISA to determine residual levels of toxin in an oral inactivated whole-cell cholera vaccine. The $G_{M1}$ ganglioside-binding ELISA was shown to be very sensitive and capable of detecting as little as 1 ng/ml of cholera toxin.

• IMMUNE NETWORK
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• 제5권2호
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• pp.55-67
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• 2005

Cancer vaccine is an active immunotherapy to stimulate the immune system to mount a response against the tumor specific antigen. Working as a stimulant to the body's own immune system, cancer vaccines help the body recognize and destroy targeted cancers and may help to shrink advanced tumors. Research is currently underway to develop therapeutic cancer vaccines. It is also possible to develop prophylactic vaccines in the future. The whole cell approach to eradicate cancer has used whole cancer cells to make vaccine. In an early stage of this approach, whole cell lysate or a mixture of immunoadjuvant and inactivated cancer cells has been used. Improved vaccines are being developed that utilize cytokines or costimulatory molecules to mount an attack against cancer cells. In case of melanoma, these vaccines are expected to have a therapeutic effect of vaccine. Furthermore, it is attempting to treat stomach cancer, colorectal cancer, pancreatic cancer, and prostate cancer. Other vaccines are being developing that are peptide vaccine, recombinant vaccine and dendritic cell vaccine. Out of them, reintroduction of antigen-specific dendritic cells into patient and DNA vaccine are mostly being conducted. Currently, research and development efforts are underway to develop therapeutic cancer vaccine such as DNA vaccine for the treatment of multiple forms of cancers.

• Clinical and Experimental Pediatrics
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• 제55권9호
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• pp.309-315
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• 2012

Human respiratory syncytial virus (HRSV) is a major cause of severe respiratory tract illnesses in infants and young children worldwide. Despite its importance as a respiratory pathogen, there is currently no licensed vaccine for HRSV. Following failure of the initial trial of formalin-inactivated virus particle vaccine, continuous efforts have been made for the development of safe and efficacious vaccines against HRSV. However, several obstacles persist that delay the development of HRSV vaccine, such as the immature immune system of newborn infants and the possible Th2-biased immune responses leading to subsequent vaccine-enhanced diseases. Many HRSV vaccine strategies are currently being developed and evaluated, including live-attenuated viruses, subunit-based, and vector-based candidates. In this review, the current HRSV vaccines are overviewed and the safety issues regarding asthma and vaccine-induced pathology are discussed.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8019-8029
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• 2016

The development of new strategies for vaccine delivery for generating protective and long-lasting immune responses has become an expanding field of research. In the last years, it has been recognized that bacteriophages have several potential applications in the biotechnology and medical fields because of their intrinsic advantages, such as ease of manipulation and large-scale production. Over the past two decades, bacteriophages have gained special attention as vehicles for protein/peptide or DNA vaccine delivery. In fact, whole phage particles are used as vaccine delivery vehicles to achieve the aim of enhanced immunization. In this strategy, the carried vaccine is protected from environmental damage by phage particles. In this review, phage-based vaccine categories and their development are presented in detail, with discussion of the potential of phage-based vaccines for protection against microbial diseases and cancer treatment. Also reviewed are some recent advances in the field of phagebased vaccines.

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.936-940
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• 2015

Human papillomavirus (HPV) type 52 is a high-risk HPV responsible for cervical cancer. HPV type 52 is common around the world and is the most common in some Asian regions. The available prophylactic HPV vaccines protect only from HPV types 16 and 18. Supplementing economical vaccines that target HPV type 52 may satisfactorily complement available prophylactic vaccines. A codon-adapted HPV 52 L1 gene was expressed in the methylotrophic yeast Hansenula polymorpha, which is used as an industrial platform for economical hepatitis B surface antigen particle production in China. We found that the recombinant proteins produced in this expression system could form virus-like particles (VLPs) with diameters of approximately 50 nm. This study suggests that the HPV 52 VLPs produced in this platform may satisfactorily complement available prophylactic vaccines in fighting against HPVs prevalent in Asia.

• 한국군사과학기술학회지
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• 제27권2호
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• pp.304-310
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• 2024

Ricin is a highly toxic protein which is produced in the seeds of the castor oil plant. Ricin toxin A chain has ribosomal RNA N-glycosylase activity that irreversibly hydrolyses the N-glycosidic bond of the adenine residue at position 4324 within the 28S rRNA. In this study, we developed non-toxic recombinant ricin vaccine(R51) in E. coli expression system, and evaluated efficacy of the R51 according to adjuvants. When the R51 was administered using aluminum hydroxide as an adjuvant, the vaccine efficacy was higher than that of TLR agonists or aluminum phosphate. Because it is time-consuming to administer the vaccine three times at three-week intervals, we investigated the survival rate and antibody titer of mice according to the change of time interval of vaccination. Interestingly, there was no difference in survival rate and antibody titer when R51 was administered at 0, 1, and 3 weeks or 0, 2, and 4 weeks compared to when administered at 0, 3, and 6 weeks. Therefore, the developed R51 vaccine is promising to protect soldiers from Ricin attack.

• 보건행정학회지
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• 제25권2호
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• pp.140-148
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• 2015

Vaccination is the most powerful and useful preparation against infectious diseases. However, developing vaccines costs a lot and requires extensive long-term efforts. Therefore, the government should research and develop vaccines with a national-level policy. To greatly enhance the success rate of vaccine development, the policy should be set up considering priorities such as the current status of domestic research, the importance for public health, the urgency of research. The Delphi technique was utilized to draft this survey, through a brainstorming stage, then two inquiries, and finally the final panel meeting where unresolved items were discussed, to draw the conclusion. Among the results, firstly, the highest ranked item on centralized fields for vaccine development by the Ministry of Health was 'self-sufficiency of vaccines.' Secondly, 'emerging infectious disease' was most highly ranked in prioritized fields of vaccine development and research. Thirdly, for the vaccine that needs to be improved and developed further by the government to improve its efficacy and safety, BCG (Bacille de Calmette) for tuberculosis was ranked the highest on both types (intradermal and subcutaneous injection) from National Immunization Programme (NIP) and non-NIP. As for the high risk pathogens, 'anthrax' and 'smallpox' were first and second, consecutively. Lastly, 'development and control of vaccine candidates' was ranked the highest for the area in need for technique development in order to improve domestic vaccine's research level. The results of this study will be put to good use as basic data for the national vaccine research and development (R&D) policy of the country. This study was first step and more studies should be carried out for the final decision of the national vaccine R&D priority.