Publications by authors named "Beom Ku Han"

Article Synopsis
  • The study aimed to enhance the production of virus-like particles (VLPs) for enterovirus 71 (EV71), which causes hand, foot, and mouth disease (HFMD).
  • Researchers focused on optimizing the expression levels of the P1 precursor protein and the 3CD protein necessary for cleaving P1, adjusting factors like promoter strength.
  • Findings showed that using a specific weakened promoter led to effective P1 and 3CD expression, resulting in high structural protein production and improved VLP formation for HFMD.
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Nucleic acid amplification tests (NAATs) are powerful tools for the Japanese encephalitis virus (JEV). We demonstrated highly sensitive, specific, and rapid detection of JEV by colorimetric reverse-transcription loop-mediated isothermal amplification (cRT-LAMP). Under optimized conditions, the RT-LAMP assay results showed that the limit of detection was approximately equivalent to 1 RNA genome copy/μL with an assay time of 30 min.

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The ongoing severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic had brought disastrous consequences throughout the entire world. While several manufactured vaccines have been approved for emergency use, continuous efforts to generate novel vaccines are needed. In this study, we developed SARS-CoV-2 virus-like particles (VLPs) containing the full length of spike (S) glycoprotein (S full), S1, or S2 together with the influenza matrix protein 1 (M1) as a core protein.

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secretes the hemolytic cytotoxins ApxI, ApxII, ApxIII, and ApxIV, which cause pleurop- neumonia in swine. Of these, ApxI is the most toxic. ApxIA, a repeats-in-toxin toxin-like protein, has strong hemolytic and cytotoxic activities.

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Article Synopsis
  • - It is commonly believed that the gene ORF1629 is crucial for baculovirus replication in insect cells, leading to the development of recombinant viruses through a baculovirus expression system.
  • - Researchers discovered that a bacmid (a modified baculovirus) could still proliferate in insect cells even when it lacked a complete ORF1629, indicating that the gene is not strictly necessary for replication.
  • - While ORF1629 is not essential, its absence resulted in slower growth rates and lower yields of the virus, along with larger but fewer occlusion bodies, affecting the overall production efficiency of baculoviruses like AcMNPV and BmNPV.
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Article Synopsis
  • The baculovirus expression system (BES) is effective for producing tough vertebrate proteins, and Ssp DnaB mini-intein serves as a beneficial fusion partner that can self-cleave under controlled conditions.
  • Recombinant viruses were created to express multiple proteins fused to the mini-intein, resulting in successful intracellular cleavage during infection, although the timing varied with each protein.
  • Overall, using Ssp DnaB mini-intein significantly boosted protein production, helping to counterbalance the loss from self-cleavage, and demonstrates its potential for easier purification and enhanced yields in BES applications.
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Modern genetic techniques, enable the use of animal bioreactor systems for the production and functional enhancement of anti-cancer antibodies. Chicken is the most efficient animal bioreactor for the production of anti-cancer antibodies because of its relatively short generation time, plentiful reproductive capacity, and daily deposition in the egg white. Although several studies have focused on the production of anti-cancer antibodies in egg white, in-depth studies of the biological activity and physiological characteristics of transgenic chicken-derived anti-cancer antibodies have not been fully carried out.

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Various new technologies have been applied for developing vaccines against various animal diseases. Virus-like particle (VLP) vaccine technology was used for manufacturing the porcine circovirus type 2 and RNA particle vaccines based on an alphavirus vector for porcine epidemic diarrhea (PED). Although VLP is classified as a killed-virus vaccine, because its structure is similar to the original virus, it can induce long-term and cell-mediated immunity.

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Currently, transgenic animals have found a wide range of industrial applications and are invaluable in various fields of basic research. Notably, deposition of transgene-encoded proteins in the egg white (EW) of hens affords optimal production of genetically engineered biomaterials. In the present study, we developed a minisynthetic promoter modulating transgene transcription specifically in the hen's oviduct, and assayed the bioactivity of human epidermal growth factor (hEGF) driven by that promoter, after partial purification of epidermal growth factor (EGF) from transgenic hen eggs.

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Purpose: House dust mites (HDMs) are an important source of indoor allergens associated with asthma, rhinitis and atopic dermatitis. Chicken immunoglobulin (Ig) Y is known to be a good alternative to mice and rabbit antibody production. In this study, we produced IgYs specific to HDMs and investigated their IgE immunoreactivities.

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Glucose phosphate isomerase (GPI) involves in the reversible isomerization of glucose-6-phosphate to fructose-6-phosphate in glucose pathways. Because glucose metabolism is crucial for the proliferation and differentiation of embryonic stem and germ cells, reducing GPI expression may affect the characteristic features of these cells. MicroRNAs (miRNAs) have been shown to regulate genes.

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Chicken oviductal epithelium produces large quantities of egg white protein in daily cycles. In this study, we cultured and characterized oviductal epithelial cells (OECs) from juvenile (10-wk-old) chickens and from actively laying (30-wk-old) hens. The juvenile OECs were maintained over passage 25 and were positive for toluidine blue, lectin-ConA, HPA, UEA-1, WFA, WGA, anti-OVA, anti-ESR1, and anti-PGR, whereas the adult OECs were cultured over passage 6 and were positive for toluidine blue, periodic acid-Schiff, lectin-ConA, WFA, WGA, anti-OVA, anti-ESR1, and anti-PGR.

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Background: Although chicken oviduct is a useful model and target tissue for reproductive biology and transgenesis, little is known because of the highly specific hormonal regulation and the lack of fundamental researches, including lectin-binding activities and glycobiology. Because lectin is attached to secreted glycoproteins, we hypothesized that lectin could be bound to secretory egg-white proteins, and played a crucial role in the generation of egg-white protein in the oviduct. Hence, the purpose of this study was to investigate the structural, histological and lectin-binding characteristics of the chicken oviductal magnum from juvenile and adult hens.

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We report the tissue-specific distribution of chitinolytic activity in Korean ginseng root and characterize two 31-kDa chitinolytic enzymes. These two enzymes (SBF1 and SBF2) were purified 70- and 81-fold with yields of 0.75 and 1.

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The use of genetically modified germ cells is an ideal system to induce transgenesis in birds; the primordial germ cell (PGC) is the most promising candidate for this system. In the present study, we confirmed the practical application of this system using lentivirus-transduced chicken gonadal PGCs (gPGCs). Embryonic gonads were collected from 5.

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Although chicken spermatogonial stem cells (SCs) are important in spermatogenesis and transgenic research, little is known about these cells. Recently, our group constructed an in vitro culture system to establish germline stem cells (GSCs). To examine the mechanism of chicken spermatogonial SC development, we constructed a proteome map of GSCs from 4-week-old chicken testes.

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Members of the Pumilio (Pum) family of RNA-binding proteins act as translational repressors and are required for germ cell development and asymmetric division. We identified the chicken Pum1 and Pum2 genes and analyzed their expression patterns in various tissues. Comparative sequence analysis of the Pum1 and Pum2 proteins from the drosophila, chicken, mouse, and human revealed a high degree of evolutionary conservation in terms of the levels of homology of the peptide sequences and the structure of Pumilio homology domain (PUM-HD), C-terminal RNA-binding domain, with similar spacing between the adjacent Pum eight tandem repeats.

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We established a database to study germ cells during the early developmental stage in the chicken. The ChickGCE database provides integrated expressed sequence tag (EST) data from chicken testis, ovary, embryonic gonads, and primordial germ cells. We gathered data on 10,294 ESTs from approximately 1000 embryonic gonads, and we experimentally determined 10,851 ESTs from primordial germ cells purified from 7955 embryonic gonads by magnetically activated cell sorting.

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The domestic chicken (Gallus gallus) is an important model for research in developmental biology because its embryonic development occurs in ovo. To examine the mechanism of embryonic germ cell development, we constructed proteome map of gonadal primordial germ cells (gPGCs) from chicken embryonic gonads. Embryonic gonads were collected from 500 embryos at 6 days of incubation, and the gPGCs were cultured in vitro until colony formed.

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Chicken monoclonal antibody (mAb), 8C3, which is reactive with a sporozoite antigen of Eimeria acervulina, is a potential therapeutic agent against avian coccidiosis caused by Eimeria spp. However, production of large amounts of 8C3 mAb in cell culture system is labor intensive and not cost-effective. Accordingly, recombinant single chain variable fragment (ScFv) antibody was constructed by amplification of the V(H) and V(L) genes from chicken hybridoma, 8C3 and when expressed in E.

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