• IMMUNE NETWORK
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• v.5 no.2
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• pp.68-77
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• 2005

Background: Costimulation is a critical process in Ag-specific immune responses. Both B7.1 and CD28 molecules have been reported to stimulate T cell responses during antigen presentation. Therefore, we tested whether Ag-specific immune responses as well as protective immunity are influenced by coinjecting with B7.1 and CD28 cDNAs in a mouse HSV-2 challenge model system. Methods: ELISA was used to detect levels of antibodies, cytokines and chemokines while thymidine incorporation assay was used to evaluate T cell proliferation levels. Results: Ag-specific antibody responses were enhanced by CD28 coinjection but not by B7.1 coinjection. Furthermore, CD28 coinjection increased IgG1 production to a significant level, as compared to pgD+pcDNA3, suggesting that CD28 drives Th2 type responses. In contrast, B7.1 coinjection showed the opposite, suggesting a Th1 bias. B7.1 coinjection also enhanced Ag-specific Th cell proliferative responses as well as production of Th1 type cytokines and chemokines significantly higher than pgD+pcDNA3. However, CD28 coinjection decreased Ag-specific Th cell proliferative responses as well as production of Th1 types of cytokines and chemokine significantly lower than pgD+pcDNA3. Only MCP-1 production was enhanced by CD28. B7.1 coimmunized animals exhibited an enhanced survival rate as well as decreased herpetic lesion formation, as compared to pgD+pcDNA3. In contrast, CD28 vaccinated animals exhibited decreased survival from lethal challenge. Conclusion: This study shows that B7.1 enhances protective Th1 type cellular immunity against HSV-2 challenge while CD28 drives a more detrimental Th2 type immunity against HSV-2 challenge, supporting an opposite role of B7.1 and CD28 in Ag-specific immune responses to a Th1 vs Th2 type.

• BMB Reports
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• v.51 no.5
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• pp.207-208
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• 2018

Chitinase-Like Proteins (CLPs) are an evolutionarily conserved protein which lose their enzymatic activity for degrading chitin macromolecules. Chitinase-3-like-1 (Chi3l1) is a type of CLP that is highly expressed in epithelial cells, macrophages, etc., and is known to have correlations with type 2 inflammation and cancer. Although the increased level of Chi3l1 in the blood was reported in various disease patients, the function of Chi3l1 in adaptive immunity has been totally unknown. Recently, we found that Chi3l1 is expressed in T cells and has a negative regulatory role in T-cell activation and proliferation. A genetic ablation study of Chi3l1 in T cells showed hyperresponsiveness to TcR stimulation, which increased proliferation and Th1 differentiation. A significant increase of $IFN{\gamma}$ signaling in Chi3l1-deficient T cells synergistically increased Th1 and CTL functions against melanoma cells in vitro and in vivo. In addition, targeted knockdown by Chi3l1 siRNA complexed with the cell-penetrating peptide dNP2, which showed decreased pulmonary melanoma metastasis with increased infiltration of Th1 and CTL in the lung. This study first suggests that Chi3l1 is a novel regulator of Th1/CTL responses and could be a target for treating cancer to increase tumor immunity.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.399-405
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• 1997

Progesterone is necessary for successful pregnancy and had immunosuppressive properties. Peripheral blood mononuclear cells (PBMC) from many women with unexplained recurrent spontaneous abortion responded to trophoblast extract in vitro by prolifertion and releasing soluble, heat-labile factors that are toxic to mouse embryos (embryotoxic factors). Accumulating evidence suggests that T Helper (Th)-1 type immunity to trophoblast is correlated with embryotoxic factor production and is associated with pregnancy loss, while Th2-type immunity is associated with successful gestation. The objective of this study was to determine whether progesterone can inhibit Th1-type cytokine secretion (IFN-${\gamma}$, TNF-${\alpha}$) by trophoblast-activated peripheral blood mononuclear cells from 23 nonpregnant women (age 25-35) with unexplained recurrent abortion (median 5, range 3 to 15)who otherwise produce embryotoxic factors in response to trophoblast. We also determined whether progesterone affected Th2-type cytokines (IL-4, IL-10) in this system in vitro and if IL-10 (1,500 pg/mL) could inhibit Th1-type immunity to trophoblast. IFN-${\gamma}$ was detected in 17 of 23 (74%) trophoblast stimulated PBMC culture supernatants ($77.94{\pm}23.79$ pg/mL) containing embryotoxic activity. TNF-${\alpha}$ was detected in 19 (83%) of these same supernatants ($703.15{\pm}131.36$ pg/mL). In contrast, none of the supernatants contained detectable levels of IL-4 or IL-10. Progesterone ($10^{-5}$, $10^{-7}$, $10^{-9}$M) inhibited Th1-type immunity in a dose dependent manner, but had no effect on Th2-type cytokine secretion. The inhibitory effects of progesterone were abrogated with RU486, but did not affect Th2-type cytokine secretion in trophoblast-activated cell cultures. IL-10, like progesterone also inhibited Th1-type cytokine secretion but had no effect on Th2-type cytokines. These data suggest that therapies designed to suppress Th1-type cytokine secretion in women with recurrent abortion who have evidence of Th1-type immunity to trophoblast may be efficacious in preventing pregnancy loss and should be tested in appropriately designed clinical trials.

• Clinical and Experimental Pediatrics
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• v.53 no.12
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• pp.985-988
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• 2010

The innate immune response is the first line of defense against microbial infections. Innate immunity is made up of the surface barrier, cellular immunity and humoral immunity. In newborn, immunologic function and demands are different to adults. Neonatal innate immunity specifically suppresses Th1-type immune responses, and not Th2-type immune responses, which are enhanced. And the impaired response of macrophages is associated with the defective innate immunity in newborn period. Toll-like receptors (TLRs) play a key roles in the detection of invading pathogens and in the induction of innate immune responses. In newborn, the expression of TLRs is age dependent, so preterm has low expression of TLRs. Also, there are defects in signaling pathways downstream of TLRs. As a consequence, the defects of TLRs activity cause the susceptibility to infection in the neonatal period.

• IMMUNE NETWORK
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• v.16 no.1
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• pp.1-12
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• 2016

Th2 cell immunity is required for host defense against helminths, but it is detrimental in allergic diseases in humans. Unlike Th1 cell and Th17 cell subsets, the mechanism by which dendritic cells modulate Th2 cell responses has been obscure, in part because of the inability of dendritic cells to provide IL-4, which is indispensable for Th2 cell lineage commitment. In this regard, immune cells other than dendritic cells, such as basophils and innate lymphoid cells, have been suggested as Th2 cell inducers. More recently, multiple independent researchers have shown that specialized subsets of dendritic cells mediate Th2 cell responses. This review will discuss the current understanding related to the regulation of Th2 cell responses by dendritic cells and other immune cells.

• YAKHAK HOEJI
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• v.56 no.6
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• pp.366-371
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• 2012

In this present study, we determined whether or not there is an immunoadjuvant effect of ochnaflavone, a biflavone isolated from Lonicera japonica. As an antigenic source, the cell wall (CACW) of Candida albicans, a fungal pathogen, was used. CACW consists of 95% carbohydrate (mannan). In the experiments, BALB/c mice were immunized with emersion forms of CACW combined with or without ochnaflavone (Och) in the presence of IFA containing mineral oil or CACW alone. Then, the amounts of antisera collected from these mice groups were measured by the ELISA method. Data from these experiments showed that CACW combined with Och (CACW/Och/IFA) provoked the production of antisera app. 2.2 or 5 times more than the corresponding CACW/IFA or CACW alone (CACW/DPBS), respectively, in mice (P<0.05). We further examined the immune response type induced by Och. Analysis of the values of the IgG1/IgG2a ratios obtained from IgG isotyping revealed that Och induced Th2-immunity more dominantly than Th1. This finding was confirmed by cytokine profile. CACW/Och/IFA formulation induced IL-4 (Th2-type cytokine) more than IFN${\gamma}$ (Th1-type cytokine) as compared with CACW/IFA and CACW/DPBS formulations (P<0.05). All data combined, Och appears to have an immunoadjuvant activity that may convert Th1 immunity into Th2 immunity.

• IMMUNE NETWORK
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• v.13 no.6
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• pp.227-234
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• 2013

The intestinal immune system has an ability to distinguish between the microbiota and pathogenic bacteria, and then activate pro-inflammatory pathways against pathogens for host defense while remaining unresponsive to the microbiota and dietary antigens. In the intestine, abnormal activation of innate immunity causes development of several inflammatory disorders such as inflammatory bowel diseases (IBD). Thus, activity of innate immunity is finely regulated in the intestine. To date, multiple innate immune cells have been shown to maintain gut homeostasis by preventing inadequate adaptive immune responses in the murine intestine. Additionally, several innate immune subsets, which promote Th1 and Th17 responses and are implicated in the pathogenesis of IBD, have recently been identified in the human intestinal mucosa. The demonstration of both murine and human intestinal innate immune subsets contributing to regulation of adaptive immunity emphasizes the conserved innate immune functions across species and might promote development of the intestinal innate immunity-based clinical therapy.

• IMMUNE NETWORK
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• v.12 no.5
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• pp.196-206
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• 2012

Besides their role as building blocks of protein, there are growing evidences that some amino acids have roles in regulating key metabolic pathways that are necessary for maintenance, growth, reproduction, and immunity. Here, we evaluated the modulatory functions of several amino acids in protective immunity against mucosal infection of herpes simplex virus type 1 (HSV-1). We found that glutamine (Gln) and leucine (Leu) showed enhanced protective immunity to HSV-1 mucosal infection when two administration of Gln and single administration of Leu per day, but not when administered in combinations. Ameliorated clinical signs of HSV-1 challenged mice by the intraperitoneal administration of Gln and Leu were closely associated with viral burden and IFN-${\gamma}$ production in the vaginal tract at 2 and 4 days post-infection. In addition, the enhanced production of vaginal IFN-${\gamma}$ appeared to be caused by NK and HSV-1 antigen-specific Th1-type CD4+ T cells recruited into vaginal tract of mice treated with Gln and Leu, which indicates that IFN-${\gamma}$, produced by NK and Th1-type CD4+ T cells, may be critical to control the outcome of diseases caused by HSV-1 mucosal infection. Collectively, our results indicate that intraperitoneal administration of Gln and Leu following HSV-1 mucosal infection could provide beneficial effects for the modulation of protective immunity, but dosage and frequency of administration should be carefully considered, because higher frequency and overdose of Gln and Leu, or their combined treatment, showed detrimental effects to protective immunity.

• Molecules and Cells
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• v.24 no.1
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• pp.132-138
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• 2007

4-1BB (CD137), a member of the tumor necrosis factor receptor superfamily, is expressed on activated T-cells, and 4-1BB signaling due to interaction with 4-1BB ligand or ligation with anti-4-1BB monoclonal antibody (mAb) costimulates T cells. It has been shown that administration of anti-4-1BB mAb induces anti-tumor immunity in mice, but the nature of the cellular subsets responsible for this immunity is uncertain. In this study we found that anti-4-1BB mAb administration to B16F10 melanoma-bearing mice induced marked expansion of $CD11c^+CD8^+$ T-cells in parallel with suppression of pulmonary tumors. The mAb-treated mice produced higher levels of $IFN-{\gamma}$ in their tumor tissues, spleen and lymph nodes than mice exposed to control antibody. When the $CD11c^+CD8^+$ T-cells were purified and re-stimulated in vitro, they produced high levels of the Th1 cytokines, $IFN-{\gamma}$ and IL-2, but low levels of the Th2 cytokines, IL-4 and IL-10. Furthermore, they expressed high levels of 4-1BB and CD107a, a marker of activated cytotoxic T-lymphocytes. Our results suggest that $CD11c^+CD8^+$ T-cells play a role in the anti-tumor immunity induced by anti-4-1BB mAb.

• Journal of Nutrition and Health
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• v.26 no.1
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• pp.3-12
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• 1993

This study was performed to investigate effects of dietary fat content and degree of saturation on the function of the immune system. Sixty male BALB/c mice average-weighing 17g were divided into three dietary groups: 5% safflower oil group, 20% safflower oil group, 19.3% beef tallow & 0.7% safflower oil group. Food intake and body weight were measured every day. At 4th, 7th, 10th week after dietary treatment, organ weight measurements, delayed-type hypersensitivity test, plaque forming cell test, agglutination test, differential white cell count and histological examination of spleen were performed. Results are follows; 1) Body weight, food intake and calorie intake were not different in the three dietary groups during the experimental period($\alpha$=0.05). 2) Liver weight was significantly higher in 5% safflower oil group($\alpha$=0.05). Spleen index was slightly higher in mice fed 5% safflower oil and 19.3% beef tallow & 0.7% safflower oil. Thymus index in all mice was decreased by aging. 3) Delayed-type hypersensitivity of the mice fed 5% safflower oil and 19.3% beef tallow & 0.7% safflower oil was significantly higher than that of the mice fed 20% safflower oil. 4) The number of plaque forming cell was significantly reduced at 10th week compared to 7th week in all group($\alpha$=0.05). Although there was no difference in plaque forming cell among three groups at 10th week, 5% safflower oil group showed slightly higher plaque forming cell than 20% safflower oil group at 7th week. 5) At 4th week, agglutination test seems to be higher in 5% safflower oil group and 19.3% beef tallow & 0.7% safflower oil group compared to 20% safflower oil group. 6) Percentage of neutrophil and eosinophil was slightly reduced in 20% safflower oil group. 7) Spleen tissue was not affected by and dietary treatments. According to our results, the higher the fat content & unsaturation of the diet the lower the cell-mediated immunity of the mice. Humoral-immunity did not appear to be affected by the dietary manipulation. However humoral-immunity was decreased significantly by aging in all dietary groups.