• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.549-557
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• 2019

Staphylococcal enterotoxin is a very common cause of food poisoning. Conventional detection methods for the toxin including enzyme-linked immunosorbent assays (ELISAs), chemiluminescence (ECL), and polymerase chain reaction (PCR) assays require a lot of time, efforts, and expert technicians. Lateral flow strip kits have shown great potential for the rapid detection of foodborne pathogens. The lateral flow strip kit is widely used in clinical settings because it is easy to use, fast, and cost effective. A typical lateral flow strip kit uses colloidal gold to generate a visual signal. However, the lateral flow strip kit based on colloidal gold has limited sensitivity to fulfill food safety regulation requirements. This study was performed to develop a rapid test kit for pathogenic staphylococcal enterotoxin B (SEB) in food samples. The rapid detection kit was fabricated based on a nitrocellulose lateral-flow strip. Cellulose nano beads and SEB antibodies were used as the tag and receptor, respectively, to improve the detection performance. Manually spotted SEB antibody and anti-rabbit antibody on the surface of the nitrocellulose membrane were used as test and control spots, respectively. The feasibility of the rapid test kit to detect SEB in samples was evaluated. The sensitivity of the kit was 10 ng/mL SEB spiked in PBS. Additionally, the rapid test kit could detect 1 ng/mL of SEB in chicken meat extract.

• Proceedings of the KOSOMBE Conference
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• v.1994 no.12
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• pp.187-189
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• 1994

• KSBB Journal
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• v.21 no.3
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• pp.212-219
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• 2006

The purpose of this study was to develop a assay system of host cell-derived residual proteins in final pharmaceutical products. Accurate and simple assay system for host cell-derived proteins(HCPs) is very important test item in pharmaceutical qualification control. In this study, methods for quantification of residual HCPs in recombinant anti-GPIIbIIIa antibody were developed using a process-specific immunoligand assay which was based on the Enzyme linked Immunosorbent assay(ELISA) system. The assay had a detection limit of 10.8 ng/ml of HCPs with a product concentration of 1 mg/ml. The practical implication of these results is that the developed ELISA system can be used for HCPs qualification control and this system will be applicable to develop another ELISA system of different antibody drug.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1176-1184
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• 2013

Anti-hepatocyte growth factor (anti-HGF) monoclonal antibodies (mAbs) are potential therapeutics against various cancers. Screening for high-producer clones is a time-consuming and complex process and is a major hurdle in the development of therapeutic mAbs. Here, we describe an efficient approach that allows the selection of high-producer Chinese hamster ovary (CHO) cell lines producing the novel anti-HGF mAb SFN68, which was generated previously by immunizing HGF bound to its receptor c-Met. We selected an SFN68-producing parental cell line via transfection of the dihydrofolate reductase-deficient CHO cell line DG44, which was preadapted to serum-free suspension culture, with an SFN68-expression vector. Subsequent gene amplification via multiple passages of the parental cell line in a methotrexate-containing medium over 4 weeks, followed by clonal isolation, enabled us to isolate two cell lines, 2F7 and 2H4, with 3-fold higher specific productivity. We also screened 72 different media formulated with diverse feed and basal media to develop a suboptimized medium. In the established suboptimized medium, the highest anti-HGF mAb yields of the 2F7 and 2H4 clones were 842 and 861 mg/l, respectively, which were about 10.5-fold higher than that of the parental cell line in a non-optimized basal medium. The selected CHO cell lines secreting high titers of SFN68 would be useful for the production of sufficient amounts of antibodies for efficacy evaluation in preclinical and early clinical studies.

• Clinical and Experimental Vaccine Research
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• v.12 no.4
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• pp.337-345
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• 2023

Purpose: The global fight against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has led to widespread vaccination efforts, yet the optimal dosing schedule for SARS-CoV-2 vaccines remains a subject of ongoing research. This study aims to investigate the effectiveness of administering two booster doses as the third and fourth doses at different intervals to enhance vaccine protection. Materials and Methods: This study was conducted at a military regional hospital operated by the Ministry of National Defense in Taiwan. A cohort of vaccinated individuals was selected, and their vaccine potency was assessed at various time intervals following their initial vaccine administration. The study participants received booster doses as the third and fourth doses, with differing time intervals between them. The study monitored neutralizing antibody titers and other relevant parameters to assess vaccine efficacy. Results: Our findings revealed that the potency of the SARS-CoV-2 vaccine exhibited a significant decline 80 days after the initial vaccine administration. However, a longer interval of 175 days between booster injections resulted in significantly higher neutralizing antibody titers. The individuals who received the extended interval boosters exhibited a more robust immune response, suggesting that a vaccine schedule with a 175-day interval between injections may provide superior protection against SARS-CoV-2. Conclusion: This study underscores the importance of optimizing vaccine booster dosing schedules to maximize protection against SARS-CoV-2. The results indicate that a longer interval of 175 days between the third and fourth doses of the vaccine can significantly enhance the neutralizing antibody response, potentially offering improved protection against the virus. These findings have important implications for vaccine distribution and administration strategies in the ongoing battle against the SARS-CoV-2 pandemic. Further research and largescale trials are needed to confirm and extend these findings for broader public health implications.

• Biomolecules & Therapeutics
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• v.30 no.3
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• pp.274-283
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• 2022

KRAS activating mutations, which are present in more than 90% of pancreatic cancers, drive tumor dependency on the RAS/mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/AKT signaling pathways. Therefore, combined targeting of RAS/MAPK and PI3K/AKT signaling pathways may be required for optimal therapeutic effect in pancreatic cancer. However, the therapeutic efficacy of combined MAPK and PI3K/AKT signaling target inhibitors is unsatisfactory in pancreatic cancer treatment, because it is often accompanied by MAPK pathway reactivation by PI3K/AKT inhibitor. Therefore, we developed an inRas37 antibody, which directly targets the intra-cellularly activated GTP-bound form of oncogenic RAS mutation and investigated its synergistic effect in the presence of the PI3K inhibitor BEZ-235 in pancreatic cancer. In this study, inRas37 remarkably increased the drug response of BEZ-235 to pancreatic cancer cells by inhibiting MAPK reactivation. Moreover, the co-treatment synergistically inhibited cell proliferation, migration, and invasion and exhibited synergistic anticancer activity by inhibiting the MAPK and PI3K pathways. The combined administration of inRas37and BEZ-235 significantly inhibited tumor growth in mouse models. Our results demonstrated that inRas37 synergistically increased the antitumor activity of BEZ-235 by inhibiting MAPK reactivation, suggesting that inRas37 and BEZ-235 co-treatment could be a potential treatment approach for pancreatic cancer patients with KRAS mutations.

• Journal of Sensor Science and Technology
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• v.16 no.2
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• pp.104-109
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• 2007

In this paper, we have fabricated on extended-gate field effect transistor (EGFET)-type protein sensor for the application to a CRP detection. We used the self-assembled monolayer (SAM) to adhere or entrap biomolecules, namely CRP antibodies. The experimental result shows that the proposed SAM is well immobilized on the gold gate surface. So the drain current was varied by antigen-antibody interactions on the gate surface because of the CRP charge. Experimental results related to the formation of SAM, antibody, antigen were obtained by measuring the electrical characteristics of the EGFET device.

• Journal of environmental and Sanitary engineering
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• v.15 no.1
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• pp.46-53
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• 2000

Korea has been free of malaria since the mid-1970s. Since the first malaria case was reported in 1993, the incidence of indigenous malaria has increased yearly, In this study, we planned to understand of malaria outbreak in the northern part of kyonggido. The subjects were a civilians except korean soldiers in the northern part of Kyonggido and the number of civilian malaria cases was 254 in 1997, 677 in 1998, 772 in 1999. The collected rates of Anopheles sinenis in 11 county from May to October were 10.1% to 85.1% and the monthly collected rates at June was highest. The incidence of malaria antibody according to the county was 5.4% in Paju-shi Tanhyun-myun 4.9% in Kapyong-gun Ha-myun, 3.0% in Yonchon-gun Yonchon-eup. etc. At the result of relationship between civilian cases and No. of A. sinenis, envionmental factor were showed high association.

• BMB Reports
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• v.34 no.1
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• pp.47-50
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• 2001

A one-step, two-site enzyme immunoassay was developed for measuring human alpha-fetoprotein (AFP) in serum and amniotic fluid using monoclonal antibodies (McAb) by eliminating the high-dose hook effect. Three McAbs that recognize different epitopes were selected among 16 different clones on the basis of epitope mapping, two for immobilization and one for horseradish peroxidase conjugation. This one-step immunoassay system is more convenient and rapid compared to a conventional two-step sandwich immunoassay system. It did not exhibit the hook effect to around 2.7 mg/ml of AFP, which is probably one of the highest concentrations of AFP in the serum. The dose-response curve of the system was linear to 500 mg/ml of AFP and the system could differentiate as low as 1 mg/ml of AFP The intra- and inter-assay variations were in an acceptable range; 95~104% and 97~105% respectively Its correlation with other commercial systems was around 95%.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1201-1204
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• 2000

We examined expression patterns of imc-415 gene in mammary gland and in HC11 mammary epithelial cells in culture. mRNA levels of imc-415 gene were higher at pregnancy and involution stages of mouse mammary gland compared with lactation period. Expression of imc-415 gene was induced with serum starvation or treatment with Fas monoclonal antibody in HC11 mammary epithelial cells in culture.