Selecting an appropriate antigen with optimal immunogenicity and physicochemical properties is a pivotal factor to develop a protein based subunit vaccine. Despite rapid progress in modern molecular cloning and recombinant protein technology, there remains a huge challenge for purifying and using protein antigens rich in hydrophobic domains, such as membrane associated proteins. To overcome current limitations using hydrophobic proteins as vaccine antigens, we adopted in silico analyses which included bioinformatic prediction and sequence-based protein 3D structure modeling, to develop a novel periodontitis subunit vaccine against the outer membrane protein FomA of Fusobacterium nucleatum. To generate an optimal antigen candidate, we predicted hydrophilicity and B cell epitope parameter by querying to web-based databases, and designed a truncated FomA (tFomA) candidate with better solubility and preserved B cell epitopes. The truncated recombinant protein was engineered to expose epitopes on the surface through simulating amino acid sequence-based 3D folding in aqueous environment. The recombinant tFomA was further expressed and purified, and its immunological properties were evaluated. In the mice intranasal vaccination study, tFomA significantly induced antigen-specific IgG and sIgA responses in both systemic and oral-mucosal compartments, respectively. Our results testify that intelligent in silico designing of antigens provide amenable vaccine epitopes from hard-to-manufacture hydrophobic domain rich microbial antigens.

This study investigated the changes in appetite and behavior of cattle and pigs after foot-and-mouth disease (FMD) vaccination. This study involved ten calves and ten pigs, each divided into two groups of five animals. One group of each animal was vaccinated with an FMD vaccine (FMD-V), and the other group was used as a non-treated control (CON). Each animal’s appetite and behavior were observed before vaccination and for seven days post-vaccination. In the FMD-V groups, appetite and behavior scores during the seven days post-vaccination were significantly decreased compared to those in the CON groups. The only exception was the seventh day post-vaccination in the swine behavior scores.

Brucellosis is a notorious zoonotic disease with global implications. Efforts to control the spread of the disease have been restricted to the agricultural livestock. Increasing incidences of accidental human infection have motivated researches to start working on alternative vaccines. At present, live attenuated vaccines are the only accepted type of vaccines used in developed countries for the prevention of brucellosis. Although serodiagnosis is occasionally unreliable, some countries have already claimed to have eradicated the disease, based on this testing. Live attenuated vaccines are not suitable for use in pregnant and immune-depressed animals. Moreover, these vaccines are not tolerated in humans. Therefore, many researches have been striving to discover alternative methods of vaccination. Most research has focused on the generation of subcellular, subunit, and DNA vaccines that are as efficient as the live attenuated vaccines. At present, none of the available vaccines has been able to replace the live attenuated vaccines. Therefore, additional research is necessary in order to discover a new brucellosis vaccine that is suitable for human use.

We previously developed a novel attenuated Salmonella Typhimurium (S.Typhimurium) △lon△cpxR vaccine. This study was conducted in order to examine whether this vaccine could effectively protect growing piglets against Salmonella infection. Pregnant sows in group A were primed and boosted with the vaccine, whereas pregnant sows in group B received sterile PBS-sucrose. After farrowing, newborn piglets in groups A and B were challenged with a wild type virulent S. Typhimurium at three weeks of age. During the study, serum IgG titers of piglets in group A were significantly higher than those of piglets in group B (P<0.001). In addition, clinical signs were observed in 5.9% of piglets in group A during the entire experimental period after the challenge, while diarrhea was observed in 81.6% of piglets in group B. These results indicate that vaccination of the pregnant sows resulted in effective protection in piglets against Salmonella infection.

The antigen GA733 is a cell-surface highly expressed glycoprotein on most human colorectal carcinomas. GA733 can be characterized as a cancer vaccine. In this study, GA733 was fused to the human immunoglobulin IgG Fc fragment to become recombinant gene GA733-Fc. Based on this, 4 recombinant genes were constructed as follows: GA733-Fc with signal peptide sequence and fusion of ER retention sequence (KDEL) (spGA733-FcK), GA733-Fc with signal sequence (spGA733-Fc), GA733-Fc fused to ER retention sequence (GA733-FcK) without signal peptide and GA733-Fc without signal peptide. Baculovirus-insect cell expression system is widely used for the high level production of recombinant proteins especially for glycoproteins. Constructed 4 recombinant genes were cloned to baculovirus express vectors. DH10Bac E.coli.-mediated transformation was used to generate recombinant bacmid DNA. Recombinant DNA was confirmed by PCR. Insect cell was transfected by bacmid to produce the recombinant baculovirus infects insect cell to produce recombinant protein. Western blot and sandwich ELISA showed the expression of recombinant proteins. Each cell lines (sf9 and HighFive) differed in recombinant proteins production level and protein secretion capability. N-Glycosylation analysis showed the function of signal peptide and ER retention sequence (KDEL). Taken together, baculovirus-insect cell system can be used to express recombinant GA733-Fc glycoproteins.

Nationally, flatfish vaccination has been performed manually, and is a laborious and time-consuming procedure with low accuracy. The handling requirement also makes it prone to contamination. With a view to eliminating these drawbacks, we designed an automatic vaccine system in which the injection is delivered by a Cartesian coordinate robot guided by a vision system. The automatic vaccine injection system is driven by an injection site location algorithm that uses a template-matching technique. The proposed algorithm was designed to derive the time and possible angles of injection by comparing a search area with a template. The algorithm is able to vaccinate various sizes of flatfish, even when they are loaded at different angles. We validated the performance of the proposed algorithm by analyzing the injection error under randomly generated loading angles. The proposed algorithm allowed an injection rate of 2000 per hour on average. Vaccination of flatfish with a body length of up to 500mm was possible, even when the orientation of the fish was random. The injection errors in various sizes of flatfish were very small, ranging from 0 to 0.6mm.

The objective of this study was to investigate the effect of a herd specific vaccine against Staphylococcus aureus (S. aureus) by different inoculation route, IMI (intramammary injection), Koso, and supramammary lymphnode area. Based on strains of S. aureus from a case of acute clinical mastitis in Daekwanryeong farm, two experimental vaccines were made, inactivated vaccine and sonicated one. To determine the antigen concentration of the vaccine, 220 ICR-mice were immunized by the intraperitoneal route with inactivated or sonicated experimental vaccines according to different schedules with 10 ICR mice as a control group. The sonicated vaccine was selected for further experiments in vaccination and the highest antibody titer in ELISA was observed at 3㎎/㎖ of the vaccine. The vaccine was administrated to 22 healthy cows at drying up. The quarter milk samples and bloods were collected before vaccination, right after parturition and 3 months postpartum. There were no significant differences among vaccination routes based on the antibody titers in serum and intramammary bacterial infections during drying up period. The antibody titer in serum of vaccinated cows was higher at parturition than 3 months postpartum but it had no statistical meaning, though decreased clinical signs and morbidity were observed. Results of this study suggest that the concept of the vaccine against S. aureus is to decreasing clinical mastitis rather than preventing the disease.