• Title/Summary/Keyword: cross-presentation

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Effects of cyclosporin A and tacrolimus on the cross-presentation capability of dendritic cells

  • Lee, Young-Ran;Park, Eun-Ju;Im, Sun-A;Song, Suk-Gil;Lee, Chong-Ki
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.136.2-136.2
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    • 2003
  • Previously, we showed that cyclosporin A and tacrolimus, but not rapamycin, inhibit MHC class I-restricted presentation of exogenous antigen in dendritic cells (DCs). We further characterized the effects of cyclosporin A and tacrolimus on the uptake, processing and cross-presentation of a model antigen, ovalbumin (OVA), in DCs. Treatment of DCs with cyclosporin A or tacrolimus did not inhibit phagocytic activity of DCs. Instead, treatment of DCs with cyclosporin A or tacrolimus inhibited the expression of $H-2K^b$/ molecules complexed with the OVA peptied, SIINFEKL, specifically. (omitted)

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Electron collision cross sections of molecules relevant to plasma processing

  • Jo, Hyeok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.34-34
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    • 2010
  • Absolute electron-impact cross sections for molecular targets including their radicals are important in developing plasma reactors and testing various plasma processing gases. However, low-energy electron collision data for these gases are sparse and only the limited cross section data are available. In this presentation, the methods and the status of measurements of, mainly, absolute elastic cross sections for electron-polyatomic molecule collisions will be discussed with recent results from Chungnam National University. Elastic cross sections are essential for the absolute scale conversion of inelastic cross sections, as well as for testing computational methods.

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Enhancement of Antigen Presentation Capability of Dendritic Cells and Activation of Macrophages by the Components of Bifidobacterium pseudocatenulatum SPM 1204

  • HAN Shinha;CHO Kyunghae;LEE Chong-Kil;SONG Youngcheon;PARK So Hee;HA Nam-Joo;KIM Kyungjae
    • Biomolecules & Therapeutics
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    • v.13 no.3
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    • pp.174-180
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    • 2005
  • Antigen presenting cells (APCs), dendritic cells (DCs) and macrophages, playa critical role not only in the initiation of immune responses, but also in the induction of immune tolerance. In an effort to regulate immune responses through the modulation of APC function, we searched for and characterized APC function modulators from natural products. Bifidobacterium pseudocatenulatum SPM1204 (SPM1204) isolated from feces of healthy Korean in the age of 20s was used in this experiment. DCs and macrophages were cultured in the presence of supernatants of SPM 1204 and then examined for their activities for the presentation exogenous antigen in association with major histocompatibility complexes (MHC) and macrophage activation. SPM1204 increased class I MHC-restricted presentation of exogenous antigen (cross-presentation) in a DC cell line, DC2.4 cells. The RAW 264.7 cell line was used to test the nonspecific effect of immune reinforcement of SPM1204 as a source of biological regulating modulator for the macrophage activation, include nitric oxide (NO) production and cytokine production. Results showed that the production of NO, tumor necrosis factor (TNF)-$\alpha$, interleukin 1 (IL-1)-$\beta$ and morphological changes in macrophages were largely affected by SPM1204 in a dose-dependent manner. Our results demonstrated that SPM1204 promote cross-presentation of dendritic cells as well as the induction of NO, TNF-$\alpha$ production, and activation of macrophage.

Tacrolimus and cyclosporine A inhibit both class I-restricted presentation pathway and class II- restricted presentation pathway of exogenous antigen.

  • Yang, In-Ho;Lee, Young-Ran;Kim, Hyeon-Seon;Lee, Jae-Kwon;Im, Sun-A;Li, Hong;Han , Kun;Song, Suk-Gil;Lee, Chong-Kil
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.306.2-306.2
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    • 2002
  • The main targets for the immunosuppressive calcineurin inhibitors. tacrolimus (FK-506) and cyclosporine A (CsA). have been considered to be activated T cells. but not antigen presenting cells (APCs). In the present study. we examined the effects of these drugs on the MHC-restricted presentation of exogenously added antigen. ovalbumin (OVA). in dendritic cells (DCs). Particulate form of OVA was efficiently captured. processed and presented on class I MHC molecules (cross-presentation) as well as on class II MHC molecules. (omitted)

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Non-Practice of Breast Self Examination and Marital Status are Associated with Delayed Presentation with Breast Cancer

  • Ghazali, Sumarni Mohd;Othman, Zabedah;Cheong, Kee Chee;Lim, Kuang Hock;Wan Mahiyuddin, Wan Rozita;Kamaluddin, Muhammad Amir;Yusoff, Ahmad Faudzi;Mustafa, Amal Nasir
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.2
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    • pp.1141-1145
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    • 2013
  • Delay in seeking treatment for breast cancer is a barrier to the early diagnosis and management of the disease, resulting in a poorer prognosis. We here estimated the prevalence of delayed presentation for breast cancer and identified possible influential sociodemographic factors in a cross-sectional study of 250 patients diagnosed with primary breast cancer at the Radiotherapy and Oncology Clinic in Kuala Lumpur Hospital. Data were collected by face-to-face interview using a structured questionnaire and from medical records. We examined associations between delayed presentation (presenting to a physician more than 3 months after self-discovery of a symptom) and sociodemographic characteristics, practice of breast self examination (BSE), history of benign breast disease, family history of breast cancer and type of symptom, symptom disclosure and advice from others to seek treatment using multiple logistic regression. Time from self-discovery of symptom to presentation ranged from tghe same day to 5 years. Prevalence of delayed presentation was 33.1% (95%CI: 27.4, 39.3). A significantly higher proportion of delayers presented with late stages (stage III/IV) (58.3% vs. 26.9%, p<0.001). Divorced or widowed women (OR: 2.23, 95% CI: 1.11, 4.47) had a higher risk of delayed presentation than married women and women who never performed breast self examination were more likely to delay presentation compared to those who regularly performed BSE (OR: 2.74, 95% CI: 1.33, 5.64). Our findings indicate that delayed presentation for breast cancer symptoms among Malaysian women is high and that marital status and breast self examination play major roles in treatment-seeking for breast cancer symptoms.

Formulation and Characterization of Antigen-loaded PLGA Nanoparticles for Efficient Cross-priming of the Antigen

  • Lee, Young-Ran;Lee, Young-Hee;Im, Sun-A;Kim, Kyung-Jae;Lee, Chong-Kil
    • IMMUNE NETWORK
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    • v.11 no.3
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    • pp.163-168
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    • 2011
  • Background: Nanoparticles (NPs) prepared from biodegradable polymers, such as poly (D,L-lactic acid-co-glycolic acid) (PLGA), have been studied as vehicles for the delivery of antigens to phagocytes. This paper describes the preparation of antigen-loaded PLGA-NPs for efficient cross-priming. Methods: NPs containing a similar amount of ovalbumin (OVA) but different sizes were produced using a micromixer-based W/O/W solvent evaporation procedure, and the efficiency of the NPs to induce the cross-presentation of OVA peptides were examined in dendritic cells (DCs). Cellular uptake and biodistribution studies were performed using fluorescein isothiocyanate (FITC)-loaded NPs in mice. Results: The NPs in the range of $1.1{\sim}1.4{\mu}m$ in size were the most and almost equally efficient in inducing the cross-presentation of OVA peptides via $H-2K^b$ molecules. Cellular uptake and biodistribution studies showed that opsonization of the NPs with mouse IgG greatly increased the percentage of FITC-positive cells in the spleen and lymph nodes. The major cell type of FITC-positive cells in the spleen was macrophages, whereas that of lymph nodes was DCs. Conclusion: These results show that IgG-opsonized PLGA-NPs with a mean size of $1.1{\mu}m$ would be the choice of biodegradable carriers for the targeted-delivery of protein antigens for cross-priming in vivo.

Effects of Mizoribine on MHC-Restricted Exogenous Antigen Presentation in Dendritic Cells

  • Song, Young-Cheon;Han, Shin-Ha;Kim, Hyun-Yul;Kim, Kwang-Hee;Kwon, Jeung-Hak;Lee, Sang-Jin;Ha, Nam-Joo;Lee, Young-Hee;Lee, Chong-Kil;Kim, Kyung-Jae
    • Archives of Pharmacal Research
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    • v.29 no.12
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    • pp.1147-1153
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    • 2006
  • Mizoribine (MZR) has been shown to possess immunosuppressive activity that selectively inhibits the proliferation of lymphocytes by interfering with inosine monophosphate dehydrogenase. The efficacy of MZR is not only in patients who have had renal transplantation, but also in patients with rheumatoid arthritis (RA), lupus nephritis, and primary nephritic syndrome. Because the exact mechanism of its immunosuppressive action is not clear, the object of this study was to examine the ability of MZR to regulate the antigen presenting cells (APCs), dendritic cells (DCs). In this work, we tested whether MZR ($1{\sim}10\;{\mu}g/mL$) could inhibit the cross-presentation of DCs. DC2.4 cells ($H-2K^{b}$) or bone marrow-derived DCs (BM-DCs) generated from BM cells of C57BL/6 mouse ($H-2K^{b}$) were cultured in the presence of MZR with OVA-microspheres, and the amount of OVA peptide-class I MHC complexes was measured by a T cell hybridoma, B3Z, that recognizes OVA (257-264 : SIINFEKL)-$H-2K^{b}$ complex and expresses-galactosidase. MZR profoundly inhibited the expression of SIINFEKL-$H-2K^{b}$ complexes. This inhibitory activity of MZR appeared to affect the phagocytic activity of DCs. MZR also decreased IL-2 production when we examined the effects of MZR on $CD4^{+}$ T cells. These results provide an understanding of the mechanism of immunosuppressive activity of MZR on the inhibition of MHC-restricted antigen presentation and phagocytic activity in relation to their actions on APCs.

The Effect of Gesture during the e-Learning Class on Cross-cultural Learners

  • Shin, Sanggyu
    • Annual Conference of KIPS
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    • 2018.10a
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    • pp.313-316
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    • 2018
  • In this paper, the authors reflect on how a lecturer's cross-cultural gestures affect learners from across cultures online and in the field teaching sessions for improving the service when to build an e-Learning system. The study extends to survey the way learners feel about cultural differences during a presentation from the research based on sociolinguistics research. Before starting a full-scale research, a preliminary study has been conducted to base the initial experiment, and analysis these result for main research.

Individual Characteristics and Social Function Attitudes on Luxury Brand Purchase Intentions (개인적 특성과 사회적 기능 태도가 명품 구매의도에 미치는 영향)

  • Lee, Hyejoo;Choo, Ho Jung
    • Journal of the Korean Society of Clothing and Textiles
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    • v.37 no.7
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    • pp.922-934
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    • 2013
  • This study investigates the motivations to purchase luxury brands by examining how individual characteristics (need for uniqueness, self-monitoring, and vanity) influence affective luxury brand attitudes and purchase intentions through two social function attitudes (self-expression attitude and self-presentation attitude) based on the functional theory of attitudes. On-line surveys were implemented and 314 consumers between the ages of 20 and 50 were recruited. Using SPSS 18.0 and AMOS 18.0, confirmatory factor analysis for measurements and structural equation modeling analysis for hypotheses testing were implemented. The results show that the need for uniqueness and self-monitoring by consumers have positive influences on self-expression and self-presentation attitudes toward luxury brands, respectively. The results indicate that the need by consumers for uniqueness motivates a self-expression attitude toward luxury brands and that the trait of self-monitoring motivates a self-presentation attitude toward luxury brands. Consumer vanity also positively influences both social function attitudes toward luxury brands. Self-expression and self-presentation attitudes toward luxury brands have positive influences on luxury brand purchase intentions through an affective attitude that facilitates a mediating role between two social function attitudes and the purchase intentions of consumers. This research contributes to a deeper understanding of the formation process of Korean consumers' purchase intentions for luxury brands and the literature on the role of related variables (need for uniqueness, self-monitoring, vanity, self-expression, self-presentation, affective attitude, and purchase intention). The findings provide a theoretical background to launch a cross-cultural study. The conclusion discusses the practical implications and limitations.