• The Korean Journal of Zoology
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• v.28 no.3
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• pp.166-178
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• 1985

In order to express hepatitis B surface antigen $(HB_sAg)$ containing pre-surface antigen region in mammalian calls, 2.7 kb DNA fragment containing pre-surface region-$HB_sAg$ gene poly(A) addition site of HBV genome was cloned into simian virus 40(SV 40) based chimeric vector pSVOB. 2.7 kb DNA fragment was derived from pHBVD 107 containing tandem copies of the HBV genome in a head-to-tail arrangement by Bgl II digestion. Construction of the vector pSVOE involved the incorporation of SV40 sequences spanning the viral origin of replication and 72 bp repeats (enhancer) into a pBR 322 derivative lacking sequences which inhibit replication in mammalian cells. Bam HI linker was inserted at the Pvu II site in the proximity of SV40 late promoter of pSVOE and named as pSVOB. To construct the recombinant plasmid pSVBS, pHBVD 107 was digested with Bgl II to isolate 2.7kb DNA fragment and the fragment was ligated into the Bam HI site of pSVOB by ligation. Preliminary result showed that the recombinant plasmid pSVBS produced $HB_sAg$ in the monkey cell producing large T antigen (COS cell).

• Journal of Preventive Medicine and Public Health
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• v.48 no.2
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• pp.74-83
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• 2015

Objectives: To examine the sex-specific factors associated with being unaware of one's hepatitis B virus surface antigen (HBsAg) seropositivity status in a large, HBsAg-positive population of Koreans. Methods: In total, 1197 subjects aged 19 years or older who were HBsAg-positive according to data from the 2007-2012 Korea National Health and Nutrition Examination Survey were included. Subjects were considered unaware of their HBsAg seropositivity status if they answered that they had no knowledge of being previously infected by the hepatitis B virus (HBV) or diagnosed with HBV hepatitis. Multivariate Poisson regression models with robust variance estimate were used to assess the significance of the variables using weighted frequencies. Results: The majority (77.8%) of HbsAg-positive Korean adults (females, 81.9%; males, 74.6%) were unaware of their HBsAg seropositivity status. We found that sex (female: prevalence ratio [PR] 1.19), household income (low: PR, 1.15), marital status (never married: PR, 1.18), self-rated health (moderate: PR, 1.14; good: PR, 1.12), and alcohol use (at least 2-3 times/wk: PR, 1.21) were associated with being unaware. In females, age (50 to 59 years: PR, 1.29; ${\geq}70$ years: PR, 1.30), household income (low: PR, 1.37; middle-low: PR, 1.24), and marital status (never married: PR, 1.33) were associated with being unaware. In males, self-rated health (moderate: PR, 1.14; good: PR, 1.21) and alcohol use (at least 2-3 times/wk: PR, 1.21) were associated with being unaware. Conclusions: Factors related to the socioeconomic status of females and the health-related behaviors of males were found to be associated with being unaware of one's HBsAg seropositivity status.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.12
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• pp.1079-1085
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• 2000

In this paper, we propose a method of cooperative control (T-cell modeling) and selection of group behavior strategy (B-cell modeling) based on immune system in distributed autonomous robotic system (DARS). An immune system is the living bodys self-protection and self-maintenance system. these features can be applied to decision making of the optimal swarm behavior in a dynamically changing environment. For applying immune system to DARS, a robot is regarded as a B-cell, each environmental condition as an antigen, a behavior strategy as an antibody, and control parameter as a T-cell, respectively. When the environmental condition (antigen) changes, a robot selects an appropriate behavior strategy (antibody). And its behavior strategy is stimulated and suppressed by other robots using communication (immune network). Finally, much stimulated strategy is adopted as a swarm behavior strategy. This control scheme is based on clonal selection and immune network hypothesis, and it is used for decision making of the optimal swarm strategy. Adaptation ability of the robot is enhanced by adding T-cell model as a control parameter in dynamic environments.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5695-5699
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• 2012

We investigated the relationships between demographics, lifestyle characteristics, and serum total prostate specific antigen (PSA) concentration and examined the population-based distribution of total PSA by age among 2,246 Korean men with a median age of 45 years. We obtained data about demographic and lifestyle characteristics based on self-reporting using a quetionnaire. We also performed physical examinations, anthropometric measurements, and biochemical measurements. The PSA concentration increased with age and there was a significant difference in total PSA concentration between the age groups of 21-60 years and >60 years. Age >60 years, height ${\geq}1.8$ m, a low frequency of alcohol consumption, and taking nutritional supplements showed a significantly increased odds ratio for increased PSA when 3.0 ng/mL was chosen as the PSA cut-off level. Smoking status, BMI, percent body fat, diabetes mellitus, fatty liver, herbal medicine use, vitamin use, and diet were not significantly associated with total PSA regardless of the cut-off level. When interpreting a single PSA test, height, alcohol consumption, and nutritional supplement use should be considered, in addition to age.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2665-2669
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• 2015

CD4+CD25+regulatory T cells (Tregs) play a key role in regulation of immnue response and maintenance of self-tolerance. Studies have found Tregs could suppress tumor-specific T cell-mediated immune response and promote cancer progression. Depletion of Tregs can enhance antitumor immunity. Dendritic cells (DCs) are professional antigen-presenting cells and capable of activating antigen-specific immune responses, which make them ideal candidate for cancer immunotherapy. Now various DC vaccines are considered as effective treatment for cancers. The aim of this study was to evaluate variation of Tregs in BALB/C mice with hepatocellular carcinoma and investigate the interaction between tumor-derived Tregs, effector T cells (Teff) and splenic DCs. We found the percentages of Tregs/CD4+ in the peripheral blood of tumor-bearing mice were higher than in normal mice. Tumor-derived Tregs diminished the up-regulation of costimulatory molecule expression on splenic DCs, even in the presence of Teff cells and simultaneously inhibited IL-12 and $TNF-{\alpha}$ secretion by DCs.

• 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.

• IMMUNE NETWORK
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• v.16 no.2
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• pp.134-139
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• 2016

Programmed death-1 (PD-1) is a strong negative regulator of T lymphocytes in tumor-microenvironment. By engaging PD-1 ligand (PD-L1) on tumor cells, PD-1 on T cell surface inhibits anti-tumor reactivity of tumor-infiltrating T cells. Systemic blockade of PD-1 function using blocking antibodies has shown significant therapeutic efficacy in clinical trials. However, approximately 10 to 15% of treated patients exhibited serious autoimmune responses due to the activation of self-reactive lymphocytes. To achieve selective activation of tumor-specific T cells, we generated T cells expressing a dominant-negative deletion mutant of PD-1 (PD-1 decoy) via retroviral transduction. PD-1 decoy increased IFN-γ secretion of antigen-specific T cells in response to tumor cells expressing the cognate antigen. Adoptive transfer of PD-1 decoy-expressing T cells into tumor-bearing mice potentiated T cell-mediated tumor regression. Thus, T cell-specific blockade of PD-1 could be a useful strategy for enhancing both efficacy and safety of anti-tumor T cell therapy.

• IMMUNE NETWORK
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• v.5 no.3
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• pp.172-178
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• 2005

Background: Carcinoembryonic antigen (CEA) is well-known soluble tumor marker frequently detectable in peripheral blood of carcinoma patients and considered as good target for antigen-specific immunotherapy. However, it is known that the induction of immune response to CEA is very difficult because CEA is a self-antigen expressed in fetal cells and weakly expressed in normal colorectal epithelial cells. To enhance anti-tumor immunity specific for CEA, recombinant CEA protein was modified using listeriolysin O (LLO) for endosomal lysis and trans activator of transcription (Tat) domain for transducing extracellular proteins into cytoplasm. Methods: After immunization using dendritic cells pulsed with Tat-CEA, both Tat-CEA and LLO, and both Tat-CEA and Tat-LLO, antibody titer to CEA and LLO, cytotoxic T lymphocyte activity and the frequency of IFN-${\gamma}$ producing T lymphocytes were measured. Results: Immunization using DC pulsed with both Tat-CEA and Tat-LLO protein showed the increasement of production of CEA-specific antibody in serum, cytotoxic T lymphocyte activity, the frequency of IFN-${\gamma}$ secreting T cells, compared with DC pulsed with both Tat-CEA and LLO. Furthermore the ratio of CD8+T cell to $CD4^+$ cell among CEA-specific T cells was increased in group pulsed with both Tat-CEA and Tat-LLO. Conclusion: These results suggested that DC vaccine using Tat-LLO could be used for the development of effective immunotherapy for the treatment of tumor.

• Journal of Sensor Science and Technology
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• v.7 no.4
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• pp.263-270
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• 1998

Surface Plasmon Resonance (SPR) sensor system, has rapid response and high sensitivity, can be applicable for detecting reaction times of many biospecific interactions. A SPR sensor system was constructed to detect the antigen-antibody reactions of salmonella and hIgG (human immunoglobulin G). Sensor chips made of gold thin film were used for detecting biological bindings of antigen and antibody reactions. The antigen and antibody reactions for salmonella and hIgG were carried out with various time intervals to observed characteristics of these reactions using SPR sensor system. The resonance angle shift changes were clearly observed at the time of salmonella or hIgG antibody injection into sample cell since each antibody was self-assembled on gold chip surface of the sensor. It was found that the antibodies of salmonella and hIgG reacted with its sensor chip surface in 10 minutes and 60 minutes respectively. And the antigens of both salmonella and hIgG were bound to its antibody within 1 minute.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.780-786
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• 2002

An immunosensor based on surface plasmon resonance (SPR) with a self-assembled protein G layer was developed for the detection of Escherichia coli O157:H7. A self-assembled protein C layer on a gold (Au) surface was fabricated by adsorbing the mixture of 11-mercaptoundecanoic acid (MUA) and hexanethiol at various molar ratios and by activating chemical binding between free amine (-$NH_2$) of protein G and 11-(MUA) using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDAC) in series. The formation of a self-assembled protein G layer on an Au substrate and the binding of the antibody and antigen in series were confirmed by SPR spectroscopy. The surface morphology analyses of the self-assembled protein G layer on the Au substrate, monoclonal antibody (Mab) against E. coli O157:H7 which was immobilized on protein G, and bound E. coli O157:H7 extracts on Immobilized Mab against E. coii O157:H7 were performed by atomic force microscopy (AFM). The detection limit of the SPR-based immunosensor for E. coli O157:H7 was found to be about $10^4$ cells/ml.