• IMMUNE NETWORK
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• v.7 no.4
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• pp.197-202
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• 2007

Background: Immunomodulators enhancing MHC-restricted antigen presentation would affect many cellular immune reactions mediated by T cells or T cell products. However, modulation of MHC-restricted antigen presentation has received little attention as a target for therapeutic immunoregulation. Here, we report that lectins isolated from mushroom Fomitella fraxinea enhance MHC-restricted exogenous antigen presentation in professional antigen presenting cells (APCs). Methods: Lectins, termed FFrL, were isolated from the carpophores of Fomitella fraxinea, and its effects on the class I and class II MHC-restricted presentation of exogenous ovalbumin (OVA) were examined in mouse dendritic cells (DCs) and mouse peritoneal macrophages. The effects of FFrL on the expression of total MHC molecules and the phagocytic activity were also examined in mouse DCs. Results: DCs cultured in the presence of FFrL overnight exhibited enhanced capacity in presenting exogenous OVA in association with class I and class II MHC molecules. FFrL increased slightly the total expression levels of both class I (H-$2K^b$) and class II (I-$A^b$) MHC molecules and the phagocytic activity of DCs. Antigen presentation-enhancing activity of FFrL was also observed in macrophages isolated from mouse peritoneum. Conclusion: Lectins isolated from the carpophores of Fomitella fraxinea increase MHC-restricted exogenous antigen presentation by enhancing intracellular processing events of phagocytosed antigens.

• Fisheries and Aquatic Sciences
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• v.9 no.1
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• pp.14-21
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• 2006

The aim of this study was to investigate in vivo toxicity and effects of two phthalate esters (PEs), di-n-butylphthalate (DBP) and di-2-ethylhexyl phthalate (DEHP), on the immune system of the bagrid catfish, Pseudobagrus fulvidraco. Groups of experimental fish were subjected to daily intraperitoneal injections of 300 or 1000 mg $kg^{-1}$ of DBP or DEHP for 3 days, and the cellularity and functional activity of phagocytes were measured in the spleen and pronephros (head kidney). The number of spleen leukocyte cells increased significantly (p<0.05) in response to low and high doses of DEHP and DBP, respectively; however, the cellularity of the pronephros was more susceptible to higher dose of DEHP than DBP. Nonspecific immunity, as determined by the phagocytic index (PI) and phagocytic capacity (PC), was significantly depressed by DEHP at 1000 $1000mg\;kg^{-1}\;day^{-1}$ in the pronephros at 3 days after injection. Furthermore, significantly (p<0.05) increased levels of serum glutamic oxaloacetate transaminase (GOT) and glutamic pyruvate transaminase (GPT) indicated marked hepatic dysfunction in immunosuppressed fish. Treated fish showed a significant reduction in total serum protein but no significant alteration in lysozyme activity. These results demonstrate the sensitivity of the fish immune response for predicting PE-induced immunotoxicity.

• Journal of Microbiology and Biotechnology
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• v.30 no.9
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• pp.1395-1403
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• 2020

There is an increasing interest in using inactivated probiotics to modulate the host immune system and protect against pathogens. As the immunomodulatory function of heat-killed Lactobacillus brevis KCTC 12777BP (LBB) and its mechanism is unclear, we investigated the effect of LBB on immune response based on the hypothesis that LBB might exert stimulatory effects on immunity. In the current study, we demonstrate that administration of LBB can exert immune-stimulatory effects and promote clearance of foreign matters through enhancing phagocytosis. Treatment with LBB induced the production of TNF-α, IL-6, and nitric oxide in macrophages. Importantly, LBB directly increased the phagocytic activity of macrophages against bacterial particles. LBB was able to promote the production of TNF-α in bone marrow-derived macrophages and splenocytes and also increase the proliferation rate of splenocytes, suggesting that the immune-stimulating activity of LBB can be observed in primary immune cells. Investigation into the molecular mechanism responsible revealed that LBB upregulates TAK1 activity and its downstream ERK, p38, and JNK signaling pathways. To further confirm the immunomodulatory capability of LBB in vivo, we orally administered LBB to mice and assessed the effect on primary splenocytes. Splenocytes isolated from LBB-treated mice exhibited higher TNF-α expression and proliferative capacity. These results show that heat-killed L. brevis, a wildly consumed probiotic, may provide protection against pathogens through enhancing host immunity.

• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.555-566
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• 1997

This study was carried out to evaluate the cytotoxicity of rock wool fibers(RWFs) such as cell division disturbance, chromosomal and DNA damage, and mutagenicity using cultured cells. RWFs were the man made mineral fibers. In order to find the correlation between the cytotoxicity of RWFs and the phagocytic capacity of cells, the phagocytic processes were observed using scanning electron microscope. Cell division disturbance by RWFs was evaluated by the formation of multinucleated giant cells. The chromosomal damage was evaluated by the micronucleus formation. For the evaluation of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OH-dG) formation was measured utilizing calf thymus DNA. Mutagenicity was determined by the point mutation of HGPRT and the effect of RWFs on cell transformation was also observed. 1. Compared with the results of chrysotile, RWFs were no or little effect on the cell growth according to the results done by the tests of cell proliferation inhibition and relative plating efficiency. 2. The frequency of multinucleated giant cell formation was increased by the treatment of RWFs and it was dose-dependent. However, the effect of RWFs was weaker than that of chrysotile. 3. The number of micronuclei formed in the RWFs treated cells was between those of cells treated with chrysotile and those of untreated cells. 4. The 2 fold increase in the formation of 8-OH-dG in calf thymus DNA was observed in the cells treated with RWFs in the presence of $H_2O_2$. On the other hand, chrysotile had no effect on the 8-OH-dG formation. 5. RWFs had no effect on the HGPRT point mutation and cell transformation. These results showed that RWFs could induce chromosomal damage, cell division disturbance and oxidative DNA damage in the RWFs treated cells.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2006.11a
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• pp.65-65
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• 2006

• Journal of Life Science
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• v.33 no.5
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• pp.397-405
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• 2023

Although glutathione (GSH) has been shown to play an important role in the prevention of oxidative damage as an antioxidant, studies on immune regulation by it have not been properly conducted. In this study, we investigated whether luthione^®, a reduced GSH, has an immune enhancing effect in murine macrophage RAW 264.7 cells. The results of flow cytometry and immunofluorescence experiments indicated that luthione increased phagocytic activity, a representative function of macrophages, compared to the control cells. According to the results of the cytokine array, the expression of interleukin (IL)-5, IL-1β, and IL-27 was significantly increased in the luthione-treated cells. Luthione also enhanced the production of tumor necrosis factor-α and IL-1β through increased expression of their proteins, and increased release of the immune mediators such as nitric oxide (NO) and prostaglandin E₂ was associated with increased expression of inducible NO synthase and cyclooxygenase-2. In addition, the expression of cluster of differentiation 86, an M1 macrophage marker, was dramatically enhanced in RAW 264.7 cells treated with luthione. Furthermore, as a result of heat map analysis, we found that cytokine signaling 1/3-mediated signal transducer and activator of transcription/Janus tyrosine kinase signaling pathway was involved in the immunomodulatory effect by luthione. In conclusion, our data suggested that luthione could act as a molecular regulator in M1 macrophage polarization and enhance immune capacity by promoting macrophage phagocytic function.

• Preventive Nutrition and Food Science
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• v.10 no.4
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• pp.344-348
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• 2005

Fucoidans, high-molecular-weight sulfated polysaccharides extracted from brown seaweeds, have various biological activities. Here we examined whether fucoidan could ncrease the immunomodulation and proliferation capacity of cells in vitro. When peritoneal macrophages were treated with various concentrations of fucoidan $(1\~100{\mu}g/mL)$ for 24 hours, NO production was significantly increased. In addition, exposure of macrophages to $10{\mu}g/mL$ of fucoidan induced a phagocytic activity. Treatment of neuroblastoma cells (SK-N-SH) with fucoidan enhanced cell proliferation and NO production in a concentration-dependent manner. These results indicate that fucoidan has both immunomodulatory and cell proliferative properties, and may thus be a candidate for development as an immunomodulating agent.

• Biomedical Science Letters
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• v.9 no.2
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• pp.85-91
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• 2003

Gentiana scabra var. buergeri (G. scabra) is a herb known to have therapeutic effect in infection diseases. We studied cellular activation and antitoxoplasmosis in macrophages after G. scabra stimulation. Macrophage activation was detected by nitrite production. Macrophages were treated with G. scabra extracted with water or methanol. Maximal nitrite production was detected in macrophages after stimulation of G. scabra extract 0.1 mg/ml. Maximal nitrite concentration was 23.22 0.003 uM/L in macrophages after water extract of G. scabra and was 24.07 1.41 uM/L after methanol extract of G. scabra. Effect of G. scabra in the phagocytic capacity of macrophages was monitored by using PI (percentage of macrophage infected by T gondii) method. The minimum PI (42.5 2.31) was detected in macrophages treated by water extract of G. scabra 0.1 mg/ml before infection of T gondii. We also examined toxoplasmastatic capacity of macrophage using FI (fold increase) method. The minimum FI (4.46 1.16) was shown in macrophages after water extract of G. scabra 0.1 mg/ml pretreatment before infection. Under electron microscope, proliferation of T gondii was inhibited by extract of G. scabra treatment in macrophages and the mitochondrion and lysosomal vacuoles within cells were increased. Taken together, G. scabra extract activates macrophages and induces toxopalsmastatic activity after T gondii infection. It is suggested that G. scabra may be used as a therapeutic drug against toxoplasmosis.

• Journal of fish pathology
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• v.12 no.1
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• pp.16-23
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• 1999

The immunomodulatory effects of levamisole (LMS) were evaluated in leucocytes of eels in vitro. Proliferation of lymhocytes treated with T-cell mitogen (Con A or PHA) was markedly inhibited by LMS in a dose dependent manner. B cell mitogen (LPS), in contrast, slightly increased the proliferaion. On the other hand, production of MIF and MAF when treated with Con A was increased in a dose-dependent way. NK cell activities were somewhat increased when LMS was pretreated and this augmentation was due to an increase in binding capacity of effector-target cell, but not due to the target cell lytic activity of effector cells. Phagocytic activity, superoxide anion formation, hydrogen peroxide formation and lysozyme activity of leucocytes were enhanced by LMS in a dose related-manner. These results suggest that LMS might modulate the immmune responses by activation of cytokine production and by augmentation of leukocyte activity but not by increment of immunocompetent cell numbers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.469-474
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• 2004

The objective of the current study was to determine the effects of arabinoxylane and polysaccharide peptide (PSP) on the immune cell functions. Both arabinoxylane and PSP increased plaque forming cell (10-15%) and rosette forming cell (10-30%) formation. Stimulation of macrophage with PSP (18%) and arabinoxylane (22%) resulted in increased phagocytic effects. Both arabinoxylane and PSP induced the tumor suppressive effect in mice injected sarcoma-180 cell intracutaneously. When the mice injected intraperitoneal cavity with sarcoma 180 cells, survival ratio was increased in the mice fed on arabinoxylane and PSP. The ratio of PCA was slightly decreased in the mice fed on PSP, especially fed on arabinoxylane than in the control mice. The concentrations of blood histamine were slightly decreased in the mice fed on arabinoxylane and PSP. These results suggest that the capacity of arabinoxylane and PSP seems to act as a potent immunomodulator causing augmentation of immune cell activity, and with the absence of notable side-effects, arabinoxylane and PSP could be used as a biological response modifier having possible therapeutic effects against immunological disorders.