• 대한의생명과학회지
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• 제29권4호
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• pp.344-354
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• 2023

This study emphasizes the importance of early diagnosis and response to COVID-19, leading to the development of a rapid diagnostic kit using quantum dots. The research focuses on finely tuning bioconjugation with quantum dots to enhance the accuracy and sensitivity of COVID-19 diagnosis. We have developed a COVID-19 rapid diagnostic kit that exhibits a sensitivity more than 50 times higher than existing COVID-19 diagnostic kits. Quantum dots enable the accurate detection of COVID-19 viral antigens even at low concentrations, providing a rapid response in the early stages of infection. The COVID-19 quantum dot diagnostic kit offers quick analysis time, utilizing the quantum properties of particles to swiftly measure COVID-19 infection for immediate response and isolation measures. Additionally, this diagnostic kit allows for multiple analyses with ease, as multiple quantum dots can detect various antigens and antibodies simultaneously in a single experiment. This efficiency enhances testing, reduces sample requirements, and lowers experimental costs. The application of this diagnostic technology is anticipated in the future for early diagnosis and monitoring of other infectious diseases.

• Journal of Microbiology and Biotechnology
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• 제19권3호
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• pp.307-313
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• 2009

In order to systemically investigate the possibility of using coxsackievirus B3 (CVB3) to deliver foreign genes in vivo, a recombinant strain of CVB3 encoding the renilla gene (CVB3-renilla) was constructed. The recombinant CVB3 resulted in extensive and transient expression of the renilla protein within mouse organs, especially the pancreas. The level of expression was generally dependent upon the viral titer present. Moreover, the CVB3-renilla strain was completely attenuated. Interestingly, the recombinant CVB3 vector was expressed much more strongly in mouse organs than was a comparable adenoviral vector. The CVB3-renilla strain did not express the renilla gene in mice with pre-existing coxsackievirus-specific neutralizing antibodies, but direct organ-specific administration of the virus during open-peritoneum surgery was able to circumvent this immunity. This coxsackievirus vector may represent a useful means for delivering and expressing foreign genes in mouse models in an acute and extensive fashion.

• Journal of Korean Biological Nursing Science
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• 제8권1호
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• pp.39-48
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• 2006

Purpose: To see the effects of capsaicin on the peripheral nerve damage of intervibrissal fur in mature rats, Method: 24 female mature rats($200{\sim}250g$) are divided to 3 groups and compared with each other. Immunofluorescence dye using CGRP and PGP antibodies was performed and 8 weeks after administration of capsaicin with control group. Result: The immunopositive reaction against PGP and CGRP was reduced by the damage of epidermal and dermal endings in unmyelinated sheath and thin myelinated sheath and the group after 8weeks showed distinct positive reaction of PGP and CGRP than the group after 4 weeks which means the recover of nerves. Conclusion: As a result, capsaicin influenced on pain-related neurotransmitter like CGRP when administerd to mature rats and even though it caused the damages on unmyelinated sheath and thin myelinated sheath, the damaged nerves recovered after 8 weeks. Also the research about sensory nerve endings scattered over middle dermal and deep epidermal layers such as lanceolate, merkel reticular, Ruffini endings should be studied when the research of the inner conical body is performed. Further studies are necessary about the toxicity and effect of capsaicin on the peripheral nerve endings.

• Animal cells and systems
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• 제3권2호
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• pp.229-236
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• 1999

The recA gene plays a central role in genetic recombination and SOS DNA repair in Escherichia coli (E. coli). We have previously identified a 42 kDa RecA-like protein inducible by a variety of DNA damages from a fluorescent Pseudomonas strain sp. and characterized its inducible kinetics. In the present study, we cloned and characterized the gene encoding the RecA-like protein by immunological screening of Pseudomonas genomic expression library using polyclonal E. coli anti-RecA antibodies as a probe. From 10$^{5}$ plaques screened, five putative clones were finally isolated. Southern blot analysis indicated that four clones had the same DNA inserts and the recA-like gene was located within the 3.2 kb EcoRI fragment of Pseudomonas chromosomal DNA. In addition, the cloned recA-like gene was transcribed into an RNA transcript approximately 1.1 kb in size, as judged by Northern blot analysis. The cellular level of RNA transcript of the cloned recA-like gene was increased to an average of 5.15- fold upon treatment with DNA damaging agents such as ultraviolet (UV)- light, nalidixic acid (NA), methyl methanesulfonate (MMS), and mitomycin-C (MMC). These results suggest that the cloned gene is inducible by DNA damage similarly to the recA gene in E. coli. However, the cloned gene did not restore the DNA damage sensitivity of the E. coli recA-mutant.

• Animal cells and systems
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• 제3권3호
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• pp.337-341
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• 1999

Hepatitis C virus (HCV) is a positive strand RNA virus of the Flaviviridae family and the major cause of post-transfusion non-A, non-B hepatitis. Vaccine development for HCV is essential but has been slowed by poor understanding of the type of immunity that naturally terminates HCV infection. The DNA-based immunization technique offers the potential advantage of including cellular immune responses against conserved internal proteins of a virus, as well as the generation of antibodies to viral surface proteins. Here, we demonstrate that cell lines expressing the HCV core and/or NS3 proteins can induce a specific CTL response in mice, and these results suggest a possibility that the HCV core and NS3 DNA can be used to induce CTL activity against the antigen in mice and can be further developed as a therapeutic and preventive DNA vaccine.

• Journal of Ginseng Research
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• 제22권4호
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• pp.324-330
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• 1998

We Previously reported that Polysaccharide Isolated from panax ginseng C. A. Meyer, stimulates murine splenocytes to proliferate and to be cytotoxic against a wide range of tumor cells in MHC non-restricted manner:) Therefore, we examined the cytokine mRNA expression induced by the ginseng polysaccharide in this paper. This study demonstrates that the ginseng polysaccharide stimulates Thl type cytosine expression such as IL-2 and IFNY, and macrophage type cytokine expression such as IL-lc and GM-CSF in a dose-dependent manner at different time: IL-2 mRNA was induced at 30 min, IL-la, GM-CSF mRNA at 3 hr, IFNY at 6 hr after the ginseng polysaccharide treatment. In contrast with these, Th2 type cytokine expression such as IL-4 and IL-5 was not induced. The generation of the ginseng polysaccharide-activated killer cells which was induced at the optimal doses of 50 pEyml was neutralized in the presence of anti-lL-2, anti-lFNy, anti-IL-l ${\alpha}$ antibodies, showing the importance of these cytokines produced by the ginseng polysaccharide. In flow cytometry analysis, the blastogenesis of IgM+ cells was induced on day 3 and the number of Thy 1.21 cells, CD4+ and CD8+ cells was increased on day 5. The ginseng polysaccharide also induced blastogenesis of T cells. In conclusion, the ginseng polysaccharide may have considerable antitumor immunotherapeutic modality by stimulating the cytokine production from Thl cells and macrophage and by proliferating lymphocytes.

• BMB Reports
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• 제34권2호
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• pp.156-165
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• 2001

Leptin is a circulating non-glycosylated protein that is mainly produced in adipocytes. Leptin acts in the brain to regulate food intake and energy expenditure. Previously we reported our success in the isolation of a partial cDNA of the long form of the leptin receptor, OB-Rb, from rat spleen, and showed that leptin might also play a role in peripheral immune organs. In the present study, for the first time, the complete coding region of OB-Rb cDNA was cloned from rat splenocytes, and its nucleotide sequence was determined. The cDNA was then further expressed in E. coli and mammalian cells, thereby confirming the functional integrity of this receptor. Prokaryotically overexpressed OB-R protein was then used as an immunizing antigen in BALE/c mice to produce leptin receptor-specific antibodies. By using them, we confirmed the cell surface expression of OB-Rb in transfected CHO cells. It is our belief that the reagents, as produced in this study, will be of great use in further studies of the biological role of rat leptin.

• 센서학회지
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• 제28권6호
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• pp.355-359
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• 2019

Exosomes, known as nanoscale extracellular vesicles in the range of 30-150 nm, are known to contain clinically significant information. However, there is still insufficient information on exosomal membrane proteins for cancer diagnosis. In this work, we investigated the characteristics of the membrane proteins of exosomes shed by cultured breast cancer cell lines using a surface plasmon resonance (SPR) spectroscopy and pre-activated alkanethiols modified sensor chips. The antibodies of breast cancer biomarkers such as MCU-16, EpCAM, CD24, ErbB2, and CA19-9 were immobilized on the pre-activated alkanethiols surfaces without any activation steps. The purified exosomes were loaded onto each antibody surface. The affinity rank of the antibody surfaces was decided by the relative capture efficiency factors for the exosomes. In addition, an antibody with a relative capture efficiency close to 100% was tested with exosome concentration levels of 10⁴/µl, 10⁵/µl, and 10⁶/µl for quantitative analysis.

• Biotechnology and Bioprocess Engineering:BBE
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• 제3권2호
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• pp.82-86
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• 1998

The maltose binding protein (MBP) fusion protein system is a versatile tool to express and isolate recombinant proteins in E. coli. In this system, MBP fusion proteins are efficiently isolated from whole cell lysate using amylose conjugated agarose beads and then eluted by competition with free maltose. Since MBP is a rather large molecule (∼42 kDa), for further experiments, the MBP part is usually proteolytically cleaved from the fusion protein and subsequently removed by ion-exchange chromatography or rebinding to amylose columns after washing out excess and MBP-bound maltose. In the present study, we have developed an improved method for the removal of cleaved MBP, which is advantageous over conventional methods. In this method, factor Xa cleaved MBP fusion proteins were incubated with Sepharose beads conjugated with MBP specific monoclonal antibodies and then precipitated buy centrifugation, resulting in highly purified proteins in the supernatant.

• 한국동물위생학회지
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• 제29권1호
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• pp.1-8
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• 2006

Porcine circovirus (PCV) is a small, nonenveloped virus that contains a single-stranded circular DNA genome of about 1.76 kb and belongs to the family circoviridae. The PCV-2 has been incriminated as the cause of post-weaning multisystemic wasting syndrome (PMWS) , an emerging disease in pigs. In the present study, a PCR assay was applied to detect PCV-2 in tissue samples. The presence of PCV-2 antigen in the porcine tissues was confirmed by indirect immunofluorescence (IIF) with PCV-2 specific monoclonal antibodies. And then DNA extracted from PCV-2 positive tissues was used as a template. One oligonucleotide primer suitable for PCR was selected from a published PCV-2 sequence (Genbank). Amplified PCR product was detected the same fragment lengths of 416 bp as a control. Based on these results, it was suggested that the PCR is a simple and sensitive method for support diagnostic purposes.