• IMMUNE NETWORK
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• v.4 no.3
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• pp.166-175
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• 2004

Background: Telomerase, a ribonucleoprotein enzyme capable of synthesizing telomeric repeats, attracts attention for its possible role in determining the replicative capacity of normal somatic cells, transformed cells, and cells of the germline lineage. Differently from normal somatic cells with no telomerase activity, normal lymphocytes has been reported to have telomerase activity comparable to that found in transformed cells during development and activation, which substantiate a role in supporting the capacity of lymphocytes for extensive clonal expansion. Methods: Here, in order to define the telomerase regulation in murine T lymphocytes, telomerase activity in cloned murine $CD8^+$ T cells and naive $CD8^+$ T cells isolated from C57BL/6 mice was examined. Next, the regulatory mechanism of telomerase activity at transcriptional and post- translational levels was investigated by determining the expression level of the TERT protein, a key component for telomerase activity. Results: It was demonstrated that telomerase activity was expressed in an inactivated state as well as in an activated state in the murine $CD8^+$ T lymphocytes by using TRAP assay. The increase of telomerase activity was partially dependent on the net increase of TERT expression. Also, telomerase activity was decreased after treatment with protein kinase inhibitors, indicating that telomerase activation was prevented by inhibition of phosphorylation. Conclusion: Therefore, these results suggest that telomerase activity is constitutively expressed in the murine resting T lymphocytes and controlled by both transcriptional regulation and post- ranslational modifications.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.219-225
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• 1993

The evaluation of radiation-induced DNA double strand breaks (DSB) was made following irradiation of human lymphocytes, murine lymphocytes and EL-4 leukemia cells over a wide dose range of $^{60}Co\;{gamma}-rays.$ In lipopolysaccharide (LPS) or phytohemagglutinin (PHA)-stimulated murine lymphocytes, the slopes of the stand scission factor (SSF) revealed that lymphocytes with LPS increased DNA DSB formation by a factor of 1.432 (p<0.005). Furthermore, strand break production was relatively inefficient in the T lymphocytes compared to the B lymuhocytes. And EL-4 leukemia cells were found to form significantly more DNA DSB to a greater extent than normal lymphocytes (p<0.005). The in vitro studies of the intrinsic radiosensitivity between human lymphocytes and murine lymphocytes showed similar phasic kinetics. However, murine lymphocytes were lower in DNA DSB formation and higher in the relative radiation dose of 10 percent DNA strand breaks at 3.5 hours following ${gamma}-irradiation$ than human lymphocytes. Though it is difficult to interpret these results, these differences may be result from environmental and genetic factors. From our data, if complementary explanations for this difference will be proposed, the differences in the dose-effect relationship for the induction of DSB between humans and mice must be related to interspecies variations in the physiological condition of the peripheral blood in vitro and not to differences in the intrinsic radiation sensitivity of the lymphocytes. These results can be estimated on the basis of dose-effect correlation enabling the interpretation of clinical response and the radiobiological parameters of cytometrical assessment.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1385-1391
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• 2009

The purpose of this research was to investigate the effects of the extracts of Glycyrrhiza uralensis (GE) and the combined extracts of Glycine max Merr. and Glycyrrhiza uralensis (GGE) on the activity of murine splenocytes and macrophages. GE and GGE were administered orally twice a day for 7 days at the dose of 500 mg/kg. GE decreased the viability of T- and B-lymphocytes in splenocytes, but GGE increased the viability of B-lymphocytes in splenocytes. GE increased the population of B-lymphocytes in splenocytes, but decreased the population of T-lymphocytes and splenic $CD4^+$ cells. Also, GGE decreased the population of B-lymphocytes in splenocytes, but increased the population of T-lymphocytes and splenic $CD4^+$ cells. Furthermore, GE and GGE enhanced the phagocytic activity of peritoneal macrophages and the production of nitric oxide. These results suggest that the regulative action of immune response of GGE is more potent than their of GE.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.4
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• pp.825-830
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• 2009

The purpose of this research was to investigate the effects of Calendula officinalis extract (CE) on the activation of murine lymphocytes and macrophages. CE was administered p.o. once a day for 7 days at the concentration of 500 mg/kg. The administration of CE increased the viability of thymocytes, but decreased the viability of splenocytes. Also, CE increased the viability of thymocytes and splenocytes at the concentration of $5{\mu}g$/ml in vitro. The administration of CE did not affect the population of thymic $CD4^+$/$CD8^+$ cells and splenic $CD4^+$/$CD8^+$ cells. Furthermore, the administration of CE enhanced the phagocytic activity of peritoneal macrophages, but decreased the phagocytic activity in vitro. CE decreased the production of nitric oxide from peritoneal macrophages in vivo and in vitro system. These results suggest that CE enhance of cell viability by a direct influence on thymocytes and phagocytic activity by an indirect influence on peritoneal macrophages.

• YAKHAK HOEJI
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• v.31 no.4
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• pp.213-218
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• 1987

Twenty species of higher fungi growing in the wild were collected and studied extensively for their lectin activities by using erythrocytes of human, rabbit and mouse blood. In total, 14 species demonstrated hemagglutination with some kinds of erythrocytes. Of twenty species, eight (Boletus edulis, B. splendidus, Clavaria zollingeri, Lactaritis subzonarius, L. volemus, Russula cutefracta, Pholiota squarrosa, and P. aspera) were shown lymphoagglutination with murine splenic lymphocytes. Protein contents were estimated from the crude lectin fraction. Above mentioned eight species contained relatively high amounts of proteins than other mushrooms. Since these species had coincidently, hiig emagglutinating activity as well, we could define them as lectin-containeing mushrooms. Some species also contained mitogenic lectins toward murine splenic lymphocytes.

• YAKHAK HOEJI
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• v.39 no.3
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• pp.260-267
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• 1995

A lectin from the edible mushroom, Lentinus edodes, was purified through physiological saline extraction, ammonium sulfate fractionation and column chromatographies. On polyacrylamide gel electrophoresis, 0.05M fraction from hydroxyapatite column exhibited adjacent four sharp bands. The partially purified lectin agglutinated the erythrocytes of rabbit, mouse and rat, but not agglutinated human erythrocytes. The lectin's mitogenic effects were tested by its application to human and murine splenic lymphocytes. The results showed that the 0.05M fraction from hydroxyapatite was mitogenic, and the optimal dose of Lentinus edodes lectin was slightly lower than Con A by the culture with murine splenic and human peripheral lymphocytes. Meanwhile, its ability to agglutinate transformed cells was tested by its administration to continuous cell lines L1210 and HeLa cells. The leetin was found to be an agglutinin of tumor cell lines tested by L1210 and HeLa cells.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.444-455
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• 1991

Two kinds of new lectin fractions (LOA-I, LOA-II) were obtained from loach (Misgurnus spp.) meat by 0.15 M NaCl extraction, salt fractionation, ion exchange and hydroxyapatite column chromatographies. On polyacrylamide gel electrophoresis, LOA-I exhibited one major and a few minor bands, but LOA-II exhibited three minor bands. The partially purified loach lectins agglutinated not only erythrocytes of human B and AB type, rabbit, dog, but also murine splenic lymphocytes. Agglutinability was relatively labile at various pH and stable at increasing temperature, but was not affected by tested several metal ions. By the sugar specificity test, D-glucosamine and metyl-$\beta$-galactopyranose inhibited agglutinating activity at a final concentration of 3 mM. The lectins contained relatively high amounts of aspartic acid, valine and leucine, but sulfur containing amino acids, cystein, methionine and isoleucine were not determined. LOA-I, LOA-II lectins were nonmitogenic toward murine lymphocytes.

• The Zoological Society Korea : Newsletter
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• v.12 no.2
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• pp.87.2-87
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• 1995

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.213.2-213
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• 1995

No Abstract, See Full Text

• Parasites, Hosts and Diseases
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• v.45 no.3
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• pp.175-180
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• 2007

In order to determine the role of Peyer's patch lymphocytes (PPL) in self-clearing of Cryptosporidium parvum infection in murine models, changes in PPL subsets, their cytokine expression, and in vitro IgG1 and IgA secretions by PPL were observed in primary- and challenge-infected C57BL/6 mice. In primary-infected mice, the percentages of CD4+ T cells, CD8+ T cells, slgA+ B cells, IL-2+ T cells, and $IFN-{\gamma}+$ T cells among the PPL, increased significantly (P < 0.05) on day 10 post-infection (PI). Secretion of IgG1 and IgA in vitro by PPL also increased on day 10 PI. However, all these responses, with the exception of IgG1 and IgA secretions, decreased in challenge-infected mice on day 7 post-challenge (= day 13 PI); their IgG1 and IgA levels were higher (P > 0.05) than those in primary-infected mice. The results suggest that murine PPL play an important role in self-clearing of primary C. parvum infections through proliferation of CD4+, CD8+, IL-2+, and $IFN-{\gamma}+$ T cells, and IgG1 and IgA-secreting 8 cells. In challenge infections, the role of T cells is reduced whereas that of 8 cells secreting IgA appeared to be continuously important.