• Journal of Veterinary Clinics
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• v.25 no.2
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• pp.73-78
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• 2008

Ketamine is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist and a short-acting general anaesthetic agent for human and veterinary use. We previously reported that treatment with ketamine impairs oxidative burst activity of canine peripheral blood leukocytes. In this study, the effect of ketamine on phagocytic capacity of canine peripheral blood leukocytes was examined in vitro. Phagocytic capacity was analyzed by using a flow cytometry. Ketamine directly decreased the phagocytic capacity of peripheral blood polymorphonuclear cells (PMN) and monocytes but not total peripheral blood mononuclear cells (PBMC). In addition, the phagocytic capacity of PMN and monocytes was inhibited by the ketamine-treated PBMC but not PMN culture supernatant. These results suggest that ketamine has a direct inhibitory effect on the phagocytic capacity of canine peripheral blood phagocytes and involves the production of soluble factor(s) from canine PBMC, which may suppress the phagocytic capacity.

• Journal of Veterinary Clinics
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• v.39 no.2
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• pp.51-58
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• 2022

Quercetin, a flavonoid found in fruits and vegetables, exhibits a strong anti-inflammatory activity. The objective of this study was to examine the effect of quercetin on chemotactic activity of peripheral blood polymorphonuclear cells (PMNs) to culture supernatant from peripheral blood mononuclear cells (PBMCs) stimulated with lipopolysaccharide (LPS). In addition, we determined whether this effect is related to interleukin (IL)-8 and changes in cytoskeleton. The chemotactic activity of PMNs was evaluated by a modified Boyden chamber assay. Total cellular filamentous (F)-actin levels were measured by method of fluorescence microscopy. The levels of IL-8 mRNA and protein were measured by real time polymerase reaction method and enzyme-linked immunosorbent assay, respectively. Quercetin (0-50 µM) itself has no chemoattractant effect for PMNs. The culture supernatant from PBMCs (2 × 10⁶ cells/mL) treated with LPS (1 ㎍/mL) showed remarkable increase in chemotaxis of PMNs. However, this effect was reduced dose-dependently by treatment with quercetin. In addition, PBMCs treated with LPS revealed enhanced levels in IL-8 protein and mRNA. Co-treatment of LPS with quercetin (50 µM) in PBMCs decreased IL-8 production and expression. Treatment of quercetin (0-50 µM) on PMNs to rpIL-8 (10 nM) decreased dose-dependently the chemotactic activity of PMNs. Treatment of quercetin on PMNs to IL-8 also reduced their total cellular F-actin level. These results suggested that quercetin attenuates chemotactic activity of PMNs, which is mediated by down-regulation of IL-8 production from LPS-stimulated PBMCs and inhibition of F-actin polymerization in PMNs.

• Advances in Traditional Medicine
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• v.5 no.3
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• pp.216-230
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• 2005

Although the field of study in immune enhancing compounds is relatively new, natural products from plants represent a rich and promising source of novel molecules with immunomodulating properties, Microglial cells, the main immune effector cells of the brain, usually display a ramified morphology and low expression levels of immunologically relevant antigens such as MHC class I and class II. Since any compound which participates in activation of phagocytic cells contributes to the production of potentially toxic factors, the search for convenient in vitro test-systems and study of mechanisms of action of these agents are of great interest. Human blood polymorphonuclear (PMN) cells and primary microglial cells isolated from Sprague-Dawley rats were used as cellular screening tests for study of phagocytosis-stimulating action of immunomodulating agents. Numbers of phagocytic activity were evaluated by the phagocyte ingestion of yeast cells and NO-synthase activity, nitrite production, and nitroblue tetrazolium test were determined after phagocyte stimulation. It was possible to demonstrate that indexes of phagocytic activity can be used as quantitative indicators for measurement immunomodulating activity. As a positive control, Zymosan A-induced phagocytosis in both PMN cells and primary microglial cells was used. $IFN-{\gamma}$ (0.1 -1 U/ml) stimulated phagocytosis in PMN cells 1.2 times after 2 - 3 h incubation, although at higher concentrations (10 - 100 U/ml) it strongly inhibited phagocytosis. In a similar way, at higher concentrations, $IFN-{\gamma}$ (100 - 500 U/ml) suppressed phagocytosis in zymosan-A stimulated microglial cells. When Polypodium leucotomus, cambricum and vulgare extracts were tested alone, increased levels of phagocytosis were observed in PMN. In addition, microglial cells showed both increased phagocytosis and MHC class-II antigen expressions. Surprisingly, when PMN and microglia were treated with a combination of Polypodium and $IFN-{\gamma}$, phagocytosis was not inhibited. We did not find changes in NO-synthase activity and nitrite production in both microglia and PMN cells activated by different immunomodulating agents. These results indicate that primary microglial cell cultures as well as human PMN cells can provide reproducible quantitative results in screening phagocytic activity of different immunoactive compounds. Furthermore, both inhibitory or activation mechanisms might be studied using these in vitro experimental approaches.

• Journal of Veterinary Clinics
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• v.34 no.2
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• pp.70-75
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• 2017

Fucoidan increases the chemotactic activity of peripheral blood polymorphonuclear cells (PMNs) through interleukin (IL)-8 produced by peripheral blood mononuclear cells (PBMCs). It has been demonstrated that fucoidan can regulate the chemotaxis of PMNs by activating F-actin polymerization. The objectives of this study are to investigate the direct effect of fucoidan on the chemotaxis of porcine PMNs and to examine whether this effect is associated with changes in phosphoinositide 3-kinase (PI3K) activity. The chemotactic activity of porcine PMNs was evaluated by modified Boyden chamber assay. Akt phosphorylation activity, a main downstream of PI3K, was measured by Western blotting assay. Fucoidan itself has no chemoattractant effect for PMNs. However, direct treatment of PMNs with fucoidan showed higher chemotactic activity to porcine recombinant (pr) IL-8 than that of PMNs without fucoidan. The increased chemotactic activity of fucoidan-treated PMNs to pr IL-8 was suppressed by treatment of wortmannin, an inhibitor of PI3K. Treatment of PMNs with fucoidan also increased Akt phosphorylation level. This increase was also suppressed by wortmannin. These results suggested that fucoidan can upregulate chemotactic activity of porcine PMNs to IL-8, which is associated with PI3K activation.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.1-6
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• 2003

Immunoenhancing effects of conjugated linoleic acid (CLA) isomers (l0t-l2c CLA, 9c-11t CLA, CLA mixture, 9c-11c CLA and 9t-11t CLA) on chemotactic activity of porcine peripheral blood polymorphonuclear cells (PMN) were examined. The chemotactic activity of PMN was evaluated by a modified Boyden chamber assay. CLA isomers at higher concentration of 50 to 200$\mu$M exhibited a low viability of cells by trypan blue exclusion. CLA isomers were used at concentration of 20uM showing no cytotoxic effect and high cell viability. CLA isomers themselves were not active or slight chemotactic for PMN. But culture supernatant from mononuclear cells (MNC) treated with 10t-12c CLA, 9c-11t CLA and CLA mixture except for 9c-11c. CLA and 9t-11t CLA enhanced remarkably chemotactic activity or porcine PMN PMN migration by culture supernatant from MNC treated with CLA mixture was found to be true chemotaxis by checkboard assay. This migration was also induced by porcine recombinant interleukin (rIL)-8. PMN chemotaxis caused both culture supernatant from MNC treated with CLA mixture and porcine rIL-8 was inhibited in a dose-dependent manner by addition of anti-porcine IL-8 polyclonal antibody. Therefore, these results strongly suggested that CLA (10t-12c CLA, 9c-11t CLA and CLA mixture) could stimulate porcine MNC to release and IL-8 like chemotactic activity.

• Korean Journal of Veterinary Research
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• v.55 no.3
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• pp.199-204
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• 2015

4,4'-diaminodiphenyl sulfone (dapsone) is a sulfone drug that has antibacterial effects on a variety of bacteria, especially Mycobacterium leprae; thus, it has been used to treat leprosy. Previous studies demonstrated that dapsone inhibits integrin-mediated adherence of neutrophils and production of prostaglandin $E_2$ by polymorphonuclear leukocytes. Hence, dapsone may act in immune cells and regulate cell-mediated inflammation processes. However, its anti-inflammatory effects remain unclear. The present study demonstrated that dapsone modulates the production of inflammation-related cytokines in immune cells. We employed the spleen cells of mice, which are major immune cells, and lipopolysaccharide (LPS) as a causative agent of inflammation for experiments. Dapsone induced a proportional change in splenocyte subsets and the apoptosis of spleen cells. Interestingly, dapsone decreased the production of tumor necrosis factor-alpha and interleukin (IL)-10, but not IL-6, in LPS-treated spleen cells. In other assays, we measured the dapsone-induced production of nitric oxide (NO) and the expression of activation markers of spleen cells. Dapsone decreased NO production in LPS-treated spleen cells. Taken together, our results demonstrate that dapsone has anti-inflammatory effects in immune cells and provide new insight into the potential uses of this agent.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.10a
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• pp.591-591
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• 2007

• Nuclear Engineering and Technology
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• v.33 no.3
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• pp.255-260
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• 2001

In mammals, most of the follicles can not be ovulated, and instead, are degenerated throughout the entire reproductive period. However, the precise mechanism of follicle atresia is unknown. Three weeks old female mice (ICR strain) were ${\gamma}$-irradiated with a dose of LD$^{50}$ . Before irradiation (day 0) and at day 1, 2, and 3 after irradiation, the normal and atretic preantral and antral follicles of the left ovaries were morphologically observed. Atretic follicles at 2 days after irradiation had numerous cell debris, apoptotic cells and bodies, and polymorphonuclear leukocytes in the antral cavity. In severely atretic follicles, numerous polymorphonuclear leukocytes infiltrated into the follicle. The frequencies of atretic antral (58.0 $\pm$8.6) and preantral follicles (27.3$\pm$11.2) induced by ${\gamma}$-radiation increased to 94.0$\pm$3.4 and 86.9$\pm$7.6, respectively at 2 days after irradiation (p<0.05). The number of follicles with one or more neutrophils in the largest cross sections at 2 and 3 days after irradiation significantly increased (p<0.05). It can be concluded that ${\gamma}$-radiation triggers the recruitment of neutrophils into the follicles during degeneration. The ovarian follicles can make a role of informative biological end-point useful for disaster-prevention.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.14-20
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• 2001

Rheumatoid arthritis (RA) is one of the most typical rheumatic diseases, and is characterized by chronic inflammation, cartilage destruction and joint deformity ［1,2］. During this process, profound hypertrophic changes of the synovium with infiltration of immune cells, increased vascularity, and hyperplasia result in the formation of a synovial pannus that invades cartilage and bone ［3］. In early stages of RA, the synovial membrane begins to invade the cartilage. In established RA, the synovial membrane becomes transformed into inflammatory tissue, the pannus (Fig. 1). The cell types that occupy cartilage-pannus junctions include synovial macrophages, fibroblasts, mast cells, polymorphonuclear lymphocytes (PMNs), and displaced, probably differentiated condrocytes ［4-6］. Recent studies of rheumatoid synovial tissue have demonstrated localized accumulations of mast cells and evidence of their activation/degranulation［7］.

• Journal of Applied Biological Chemistry
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• v.43 no.3
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• pp.131-135
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• 2000

Human polymorphonuclear neutrophils undergo diaphoresis after a selectin-mediated rolling on the endothelial cells of the blood vessel wall. Extravasation is believed to be an integrin-mediated process. Galectin-1 is a small dimeric beta-galactoside-binding protein synthesized by the endotherial cells and present in the perivascular connective tissue. In this study we suggest the possible role of galectin-1 in extravasation of the activated neutrophils. MAL lectin binding study showed, that f-MetLeuPhe-activated neutrophils decrease surface sialylation and increase galectin-1 binding via exposure of new galectin-1 binding sites. Desialylated HL-60 cells also show the same decrease in MAL binding and increase in galectin-1 binding, an increase which was not observed in the presence of lactose. Galectin-1 blotting analysis detected two possible major ligands (approximately 120 and 160 kDa) of galectin-1 from the desialylated HL-60 cell lysates.