• Hanyang Medical Reviews
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• v.33 no.1
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• pp.10-16
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• 2013

Follicular helper T cells (Tfh) play a significant role in providing T cell help to B cells during the germinal center reaction, where somatic hypermutation, affinity maturation, isotype class switching, and the differentiation of memory B cells and long-lived plasma cells occur. Antigen-specific T cells with IL-6 and IL-21 upregulate CXCR5, which is required for the migration of T cells into B cell follicles, where these T cells mature into Tfh. The surface markers including PD-1, ICOS, and CD40L play a significant role in providing T cell help to B cells. The upregulation of transcription factor Bcl-6 induces the expression of CXCR5, which is an important factor for Tfh differentiation, by inhibiting the expression of other lineage-specific transcription factors such as T-bet, GATA3, and RORγt. Surprisingly, recent evidence suggests that CD4 T cells already committed to Th1, Th2, and Th17 cells obtain flexibility in their differentiation programs by downregulating T-bet, GATA3, and RORγt, upregulating Bcl-6 and thus convert into Tfh. Limiting the numbers of Tfh within germinal centers is important in the regulation of the autoantibody production that is central to autoimmune diseases. Recently, it was revealed that the germinal center reaction and the size of the Tfh population are also regulated by thymus-derived follicular regulatory T cells (Tfr) expressing CXCR5 and Foxp3. Dysregulation of Tfh appears to be a pathogenic cause of autoimmune disease suggesting that tight regulation of Tfh and germinal center reaction by Tfr is essential for maintaining immune tolerance. Therefore, the balance between Tfh and Tfr appears to be a critical peripheral tolerance mechanism that can inhibit autoimmune disorders.

• International Journal of Oral Biology
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• v.34 no.3
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• pp.131-135
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• 2009

The sublingual locus has recently received great attention as a delivery site for various immunotherapies, including those that induce allergen-specific tolerance, and for vaccines that generate protective immunity. To further understand the immune functions of the human sublingual mucosa, we characterized the distribution of various immunocytes therein by immunohistochemistry. We identified professional antigen presenting cells (APCs), including Langerhans cells (LCs) and macrophages. $CD1a^+$ and $langerin^+$ LCs were further found to be distributed in the basal and supra-basal layers of the epithelium, and macrophages were identified in the lamina propria. HLA-$DR^+$ cells were observed in both the epithelium and the lamina propria, which mirrors the tissue distribution of LCs and macrophages within these tissues. $CD3^+$, $CD4^+$, and $CD8^+$ T cells were found to be distributed along the basal layer of the epithelium and also in the lamina propria. Although B cells, plasma cells, and $Foxp3^+$ regulatory T cells (Tregs) were only occasionally observed in the human sublingual mucosa in the absence of inflammation, they did show enrichment at inflammatory sites. Hence, we have further elucidated the immune cell component distribution in human sublingual mucosa.

• The Korean Journal of Food And Nutrition
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• v.29 no.6
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• pp.1023-1029
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• 2016

Probiotic functional foods are known to have various functional effects such as intestinal regulation, modulation of immune system, reduction of allergies, and lowering of cholesterol. The purpose of this study was to select probiotic strain that is most suitable for freeze-dried coffee for the development of functional coffee products. The survival rate of probiotics, at drinking condition of coffee, at acid, at bile and after freeze-dried in coffee were measured on 1 strain isolated from commercial freeze-dried coffee, 8 strains used as fermented milk starter, 1 Bifidobacterium and 1 Bacillus coagulans. Bacillus coagulans showed the highest survival rate from $2.4{\times}10^7cfu/g$ to $2.0{\times}10^7cfu/g$ especially after freeze-drying. The results at drinking condition of coffee, at acid tolerance, at bile tolerance and at storage test showed significantly better survival rate of Bacillus coagulans than that of control (Lactobacillus casei). Especially, Bacillus coagulans showed 3.8-fold higher survival rate at acid tolerance (pH 1, 120 minutes) than control. Thus, the lactic acid-producing Bacillus coagulans is characterized as a probiotic strain suitable for functional coffee formulation and commercialization.

• Archives of Reconstructive Microsurgery
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• v.21 no.1
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• pp.34-40
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• 2012

Prevention of acute rejection in composite tissue allotransplantation without continuous immunosuppression lacks reports in worldwide literature. Recently dendritic cells (DC) gained considerble attention as antigen presenting cells that are also capable of immunologic tolerance induction. This study assesses the effect of alloantigen-pulsed dendritic cells in induction of survival in a rat hindlimb allograft. We performed hindlimb allotransplantation between donor Sprague-Dawley and recipient Fischer344 rats. Recipient derived dendritic cells were harvested from rat whole blood and cultured with anti-inflammatory cytokine IL-10. Then donor-specific alloantigen pulsed dendritic cells were reinjected into subcutaneous tissue before limb transplantation. Groups: I) untreated (n=6), II) DC injected (n=6), III) Immunosuppressant (FK-506, 2 mg/Kg) injected (n=6), IV) DC and immunouppressant injected (n=6). Graft appearance challenges were assessed postoperatively. Observation of graft appearance, H-E staning, immunohistochemical (IHC) study, and confocal immunofluoreiscece were performed postoperatively. Donor antigen pulsed host dendritic cell combined with short-term immunosuppression showed minimal mononuclear cell infiltration, regulator T cell presence, and could prolong limb allograft survival.

• Journal of Pharmacopuncture
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• v.7 no.3
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• pp.27-35
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• 2004

Beevenom immunotherapy(BVIT) in allergic patients is a well-established treatment modality for the prevention of systemic anaphylactic reactions caused by insect stings. BVIT is accompanied by increases in allergen-specific IgG, particularly the IgG4 isotype, which blocks not only IgE-dependent histamine release from basophils but also IgE-mediated antigen presentation to T cells. Inhibition of T cells after BVIT also involves decreased induction of the costimulatory molecule ICOS, which, in turn, seems to be dependent on the presence of IL-10, also associated with the inhibited status of T cells after BVIT. Suppression of T cells by IL-10 is an active process, which depends on the expression and participation of CD28. Immune tolerance in specific allergen immunotherapy might be a consequence of decreased Th2 or increased Th1 response of allergen specific T lymphocytes. BVIT shifted cytokine responses to allergen from a TH-2 to a TH-1 dominant pattern, suggesting direct effects on T cells. Many studies showed that severe side effects due to venom immunotherapy are rare. These results suggest that immunological changes after BVIT may be applied to be therapeutic alternative of general allergic diseases including beevenom allergy.

• Journal of Power Electronics
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• v.12 no.4
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• pp.567-577
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• 2012

This paper introduces a new scheme to balance the DC bus voltages of a cascaded H-bridge converter which is used as a Distribution Static Synchronous Series Compensator (D-SSSC) in electrical distribution network. The aim of D-SSSC is to control the power flow between two feeders from different substations. As a result of different cell losses and capacitors tolerance the cells DC bus voltage can deviate from their reference values. In the proposed scheme, by individually modifying the reference PWM signal for each cell, an effective balancing procedure is derived. The new balancing procedure needs only the line current sign and is independent of the main control strategy, which controls the total DC bus voltages of cascaded H-bridge. The effect of modulation index variation on the capacitor voltage is analytically derived for the proposed strategy. The proposed method takes advantages of phase shift carrier based modulation and can be applied for a cascaded H-bridge with any number of cells. Also the system is immune to loss of one cell and the presented procedure can keep balancing between the remaining cells. Simulation studies and experimental results validate the effectiveness of the proposed method in the balancing of DC bus voltages.

• Clinical and Experimental Pediatrics
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• v.55 no.7
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• pp.219-223
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• 2012

Since the first umbilical cord blood transplantation (CBT) in 1998, cord blood (CB) has now become one of the most commonly used sources of hematopoietic stem cells for transplantation. CBT has advantages of easy procurement, no risk to donor, low risk of transmitting infections, immediate availability and immune tolerance allowing successful transplantation despite human leukocyte antigen disparity. Several studies have shown that the number of cells transplanted is the most important factor for engraftment in CBT, and it limits the wide use of CB in adult patients. New strategies for facilitating engraftment and reducing transplantation-related mortality are ongoing in the field of CBT and include the use of a reduced-intensity conditioning regimen, double-unit CBT, ex vivo expansion of CB, and co-transplantation of CB and mesenchymal stem cells. Recently, the results of two international studies with large sample sizes showed that CB is an acceptable alternative source of hematopoietic stem cells for adult recipients who lack human leukocyte antigen-matched adult donors. Along with the intensive researches, development in banking process of CB will amplify the use of CB and offer the chance for cure in more patients.

• Journal of Microbiology and Biotechnology
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• v.22 no.6
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• pp.849-855
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• 2012

Plant growth-promoting rhizobacteria (PGPR) pseudomonads have a large number of lipopolysaccharides on the cell surface, which induces immune responses. Cd-resistant PGPR prevalent at the Cd-affected sites under biophytostabilization was monitored. Transmissiom electron microscopy was used to the study the behavior of tolerance of PGPR to cadmium level and its effect on pseudomonad strains (Z9, S2, KNP2, CRPF, and NBRI). An immunosensor was developed by immobilizing antibody (anti-Z9 or anti-S2) against selected PGPR on a piezoelectric quartz crystal microbalance (QCM). Immunosensors were found to supplement the inherent specificity of antigen-antibody reactions with the high sensitivity of a physical transducer. On comparison of the efficiency of detection with ELISA, the spectrophotometric technique, the developed immunosensor was found to be more sensitive, fast, and reliable even after regeneration for several times. Thus, the immunosensor may be used for future detection of PGPR strains after automation of the screening process.

• Natural Product Sciences
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• v.13 no.4
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• pp.322-327
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• 2007

Fresh Rehmanniae radix is known as a traditional medicine with anti-inflammatory and antioxidant activities. However, whether Rehmanniae radix attenuates autoimmune inflammation in lupus models characterized by T cell-dependent autoimmune disease including overproduction of proinflammatory cytokines, loss of T cell tolerance, and B cell hyperactivity remains unclear. We investigated the effect of fresh Rehmanniae radix methanol extracts (RGMeOH) on the in vitro overproduction of proinflammatory cytokines by immune cells from pristaneinduced lupus BALB/c mice. These results showed that RGMeOH remarkably attenuated Con A-increased overproduction of proinflammatory cytokines, such as IL-2, IFN-${\gamma}$, IL-6 and IL-10 by splenocytes from pristaneinduced lupus mice. RGMeOH greatly reduced LPS-induced production of TNF-${\alpha}$ by splenic macrophages from pristane-induced lupus mice, while significantly enhanced LPS-induced production of IL-10 but did not alter IL-6 by splenic macrophages and splenocytes. These findings suggest that RGMeOH may ameliorate lupus systemic inflammatory autoimmunity via down-regulation of TNF-${\alpha}$ and T cell-dependent cytokine production.

• The Journal of the Korean Society for Microbiology
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• v.22 no.3
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• pp.323-328
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• 1987

This study was attempted to investigate the effect of inosiplex on the cell-mediated immunity in the patients with lepromatous leprosy. Fourteen patients received inosiplex (6gm/day) for 1 month. About 20% of the patients (3 of 14) showed conversion of the lepromin reaction and bacteriological index was significantly decreased in 3 of 7 patients. However, inosiplex administration had no effect on the lymphocyte blastogenesis to M. leprae. The clinical evolution showed a favorable activity of the drug on cutaneous lesions in some patients. The tolerance of the drug was excellent. No side effects were observed. These results suggest that inosiplex may have a moderate immunopotential value in lepromatous leprosy.