• IMMUNE NETWORK
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• 제13권2호
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• pp.63-69
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• 2013

IL-12 is a secretory heterodimeric cytokine composed of p35 and p40 subunits. IL-12 p35 and p40 subunits are sometimes produced as monomers or homodimers. IL-12 is also produced as a membrane-bound form in some cases. In this study, we hypothesized that the membrane-bound form of IL-12 subunits may function as a costimulatory signal for selective activation of TAA-specific CTL through direct priming without involving antigen presenting cells and helper T cells. MethA fibrosarcoma cells were transfected with expression vectors of membrane-bound form of IL-12p35 (mbIL-12p35) or IL-12p40 subunit (mbIL-12p40) and were selected under G418-containing medium. The tumor cell clones were analyzed for the expression of mbIL-12p35 or p40 subunit and for their stimulatory effects on macrophages. The responsible T-cell subpopulation for antitumor activity of mbIL-12p35 expressing tumor clone was also analyzed in T cell subset-depleted mice. Expression of transfected membranebound form of IL-12 subunits was stable during more than 3 months of in vitro culture, and the chimeric molecules were not released into culture supernatants. Neither the mbIL-12p35-expressing tumor clones nor mbIL-12p40-expressing tumor clones activated macrophages to secrete TNF-${\alpha}$. Growth of mbIL-12p35-expressing tumor clones was more accelerated in the $CD8^+$ T cell-depleted mice than in $CD4^+$ T cell-depleted or normal mice. These results suggest that $CD8^+$ T cells could be responsible for the rejection of mbIL-12p35-expressing tumor clone, which may bypass activation of antigen presenting cells and $CD4^+$ helper T cells.

• Molecules and Cells
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• 제38권10호
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• pp.918-924
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• 2015

During T cell activation, mitochondrial content increases to meet the high energy demand of rapid cell proliferation. With this increase, the level of reactive oxygen species (ROS) also increases and causes the rapid apoptotic death of activated cells, thereby facilitating T cell homeostasis. Nicotinamide (NAM) has previously been shown to enhance mitochondria quality and extend the replicative life span of human fibroblasts. In this study, we examined the effect of NAM on $CD8^+$ T cell activation. NAM treatment attenuated the increase of mitochondrial content and ROS in T cells activated by CD3/CD28 antibodies. This was accompanied by an accelerated and higher-level clonal expansion resulting from attenuated apoptotic death but not increased division of the activated cells. Attenuation of ROS-triggered pro-apoptotic events and upregulation of Bcl-2 expression appeared to be involved. Although cells activated in the presence of NAM exhibited compromised cytokine gene expression, our results suggest a means to augment the size of T cell expansion during activation without consuming their limited replicative potential.

• Archives of Pharmacal Research
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• 제22권5호
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• pp.437-447
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• 1999

Type I diabetes, also known as insulin-dependent diabetes mellitus (IDDM) results from the destruction of insulin-producing pancreatic $\beta$ cells by a progressive $\beta$ cell-specific autoimmune process. The pathogenesis of autoimmune IDDM has been extensively studied for the past two decades using animal models such as the non-obese diabetic (NOD) mouse and the Bio-Breeding (BB) rat. However, the initial events that trigger the immune responses leading to the selective destruction of the $\beta$ cells are poorly understood. It is thought that $\beta$ cell auto-antigens are involved in the triggering of $\beta$ cell-specific autoimmunity. Among a dozen putative $\beta$ cell autoantigens, glutamic acid decarboxylase (GAD) has bee proposed as perhaps the strongest candidate in both humans and the NOD mouse. In the NOD mouse, GAD, as compared with other $\beta$ cell autoantigens, provokes the earliest T cell proliferative response. The suppression of GAD expression in the $\beta$ cells results in the prevention of autoimmune diabetes in NOD mice. In addition, the major populations of cells infiltrating the iselts during the early stage of insulitis in BB rats and NOD mice are macrophages and dendritic cells. The inactivation of macrophages in NOD mice results in the prevention of T cell mediated autoimmune diabetes. Macrophages are primary contributors to the creation of the immune environment conducive to the development and activation of $\beta$cell-specific Th1-type CD4+ T cells and CD8+ cytotoxic T cells that cause autoimmune diabetes in NOD mice. CD4+ and CD8+ T cells are both believed to be important for the destruction of $\beta$ cells. These cells, as final effectors, can kill the insulin-producing $\beta$ cells by the induction of apoptosis. In addition, CD8+ cytotoxic T cells release granzyme and cytolysin (perforin), which are also toxic to $\beta$ cells. In this way, macrophages, CD4+ T cells and CD8+ T cells act synergistically to kill the $\beta$ cells in conjunction with $\beta$ cell autoantigens and MHC class I and II antigens, resulting in the onset of autoimmune type I diabetes.

• Toxicological Research
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• 제17권2호
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• pp.115-121
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• 2001

Some of endocrine disruptors with sexual hormone-like effects have been increasingly reported to be immunotoxic in many species in recent several years. Phthalate esters have possible effects on the endocrine system. Prenatal exposure to di(n-butyl) phthalate (DBP) has been reported to impair the androgen-dependent development of the male reproductive tract in rat. Therefore, the immunomodulatory effect of DBP was investigated in the developing immune system of fetal and neonatal Sprague-Dawley rats. Timed-bred pregnant SD rats were given to the doses of 0, 250, 500, and 750 mg DBP/kg$\cdot$ body weight /day by gavage once a day from gestational day (GD) 5 to 18. On GD19 or GD22/postnatal day one (PD1), the dams were euthanized, and the changes in organ weights and thymus phenotypes were examined for their offsprings. At 750 mg DBP/kg$\cdot$b.w./day in maternal exposure group, GD19 fetuses showed decreases in body weight. The spleen/body weight ratios were reduced in GD 19 fetuses from the dams exposed to 500 and 750 mg DBP/kg$\cdot$b.w./day. There were no significant changes in thymus and spleen cellularities though these cellularities showed a tendency to decrease in a dose dependent way. In the DBP-exsposed GD22/PD1 offsprings, the body weights, the relative organ weights and the cellularities did not exhibit alteration. Additionally, the percentages of CD3$^{+}$(CD4$^{+}$CD8$^{+}$, CD4$^{+}$CD8$^{-}$, CD4$^{-}$CD8$^{+}$, and CD4$^{-}$CD8$^{-}$) and CD3$^{-}$(CD4$^{+}$CD8$^{+}$, CD4$^{+}$CD8$^{-}$, CD4$^{-}$CD8$^{+}$, and CD4$^{-}$CD8$^{-}$) thymocyte subsets were not changed in any DBP-treated group. The proliferative responses of splenic T cells to Con A and B cells to LPS were decreased in all DBP-exposed GD22/PD1 offsprings.

• Mycobiology
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• 제35권3호
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• pp.135-144
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• 2007

The removal efficiency of the heavy metals Zn, Pb and Cd by the zoosporic fungal species Saprolegnia delica and the terrestrial fungus Trichoderma viride, isolated from polluted water drainages in the Delta of Nile in Egypt, as affected by various ranges of pH values and different temperature degrees, was extensively investigated. The maximum removal efficiency of S. delica for Zn(II) and Cd(II) was obtained at pH 8 and for Pb(II) was at pH 6 whilst the removal efficiency of T. viride was found to be optimum at pH 6 for the three applied heavy metals. Regardless the median lethal doses of the three heavy metals, Zn recorded the highest bioaccumulation potency by S. delica at all pH values except at pH 4, followed by Pb whereas Cd showed the lowest removal potency by the fungal species and vice versa in case of T. viride. The optimum bio-mass dry weight production by S. delica was found when the fungus was grown in the medium treated with the heavy metal Pb at pH 6, followed by Zn at pH 8 and Cd at pH 8. The optimum biomass dry weight yield by T. viride amended with Zn, Pb and Cd was obtained at pH 6 for the three heavy metals with the maximum value at Zn. The highest yield of biomass dry weight was found when T. viride treated with Cd at all different pH values followed by Pb whilst Zn output was the lowest and this result was reversed in case of S. delica. The maximum removal efficiency and the biomass dry weight production for the three tested heavy metals was obtained at the incubation temperature $20^{\circ}C$ in case of S. delica while it was $25^{\circ}C$ for T. viride. Incubation of T. viride at higher temperatures ($30^{\circ}C\;and\;35^{\circ}C$) enhanced the removal efficiency of Pb and Cd than low temperatures ($15^{\circ}C\;and\;20^{\circ}C$) and vice versa in case of Zn removal. At all tested incubation temperatures, the maximum yield of biomass dry weight was attained at Zn treatment by the two tested fungal species. The bioaccumulation potency of S. delica for Zn was higher than that for Pb at all temperature degrees of incubation and Cd bioaccumulation was the lowest whereas T. viride showed the highest removal efficiency for Pb followed by Cd and Zn was the minor of the heavy metals.

• Journal of Microbiology
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• 제39권3호
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• pp.181-185
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• 2001

The morphological characteristics of newly isolated Cordyceps hepialidicola were characterized, and the phylogenetic relationships with other Cordyceps species were investigated using a sequence analysis of the internal transcribed spacer (ITS). The PCR product of 592 bp showed a homology of 92 and 91% with C. militaris and C. nutans, respectively, In an in vitro model using mouse peripheral blood mononuclear cells (PBMC), a methanol extract of C. hepialidicola induced multiple cytokines, including IFN-${\gamma}$ IL-4, and IL-18. The extract also enhanced the percentages of the CD4$\^$+/ and CD8$\sub$+/ T cells in the healthy murine PBMCs to 56.1% and 13.0%,respectively. The percentages of CD4$\^$+/ and CD8$\^$+/ in the untreated controls were 28.4 and 7.3%, and concanavalin A-treated positive controls were 62.4 and 18.3%, respectively.

• IMMUNE NETWORK
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• 제21권2호
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• pp.17.1-17.10
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• 2021

Abdominal aortic aneurysm (AAA) is a chronic dilation of the aorta with a tendency to enlarge and eventually rupture, which constitutes a major cause of cardiovascular mortality. Although T-cell infiltrates have been observed in AAA, the cellular, phenotypic, and functional characteristics of these tissue-infiltrating T cells are not fully understood. Here, we investigated the proportional changes of T-cell subsets-including CD4⁺ T cells, CD8⁺ T cells, and γδ T cells-and their effector functions in AAAs. We found that Vδ2⁺ T cells were presented at a higher frequency in aortic aneurysmal tissue compared to normal aortic tissue and PBMCs from patients with AAA. In contrast, no differences were observed in the frequencies of CD4⁺, CD8⁺, and Vδ1⁺ T cells. Moreover, we observed that the Vδ2⁺ T cells from AAA tissue displayed immunophenotypes indicative of CCR5⁺ non-exhausted effector memory cells, with a decreased proportion of CD16⁺ cells. Finally, we found that these Vδ2⁺ T cells were the main source of IL-17A in abdominal aortic aneurysmal tissue. In conclusion, our results suggest that increased Vδ2⁺ T cells that robustly produce IL-17A in aortic aneurysmal tissue may contribute to AAA pathogenesis and progression.

• Natural Product Sciences
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• 제13권3호
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• pp.207-213
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• 2007

Scutellaria baicalensis is known as a herbal medicine with anti-inflammatory and anti-oxidative activities. However, effect of Scutellaria baicalensis on lupus pathogenesis that is characterized by overproduction of proinflammatory cytokines and abnormalities in regulation, function, and interaction of immune cells remains unclear. We investigated effects of Scutellariae radix methanol extract (SBMeOH) on the production of proinflammatory cytokines and abnormal activation of T cells in vitro in pristane-induced lupus BALB/c mice. These results demonstrated that SBMeOH significantly decreased the LPS-stimulated production of $TNF-{\alpha}$, IL-6, and IL-10 by splenic and peritoneal macrophages and IL-6 and IL-10 by splenocytes from pristane-induced lupus mice. SBMeOH significantly downregulated the Con A-stimulated overproduction of IL-6, IL-10, and $IFN-{\gamma}$ by splenocytes from pristane-induced lupus mice. Also, SBMeOH significantly attenuated the Con A-induced expression of CD4+ T cells and CD69+CD4+ T cells but not CD8+ T cells in pristane-induced lupus mice. Our findings indicate that SBMeOH may ameliorate lupus pathogenic inflammation and autoimmunity via downregulation of proinflammatory cytokine production and abnormal activation of T cells.

• 대한본초학회지
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• 제24권1호
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• pp.73-78
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• 2009

Objectives : In this study, we studied the effect of Pinellia Ternata (PT) on regulatory T cells and CD3+CCR3+ Th2 cells number in asthma model mice. Methods : All mice were immunized on two different days (21 days and 7 days before inhalational exposure) by i.p. injections of 0.2 $m\ell$ alum-precipitated Ag containing 100 ${\mu}g$ of OVA bound to 4 mg of aluminum hydroxide in PBS. Seven days after the second sensitization, mice were exposed to aerosolized ovalbumin for 30 min/day on 3 days/week for 12 weeks(at a flow rate of 250 L/min, 2.5％ ovalbumin in normal saline) and PT (400, 200 mg/kg) were orally administered 3 times a week for 8 weeks. After C57BL/6 mice were orally given of PT, the percentages, cell numbers, phenotype and function of CD4+CD25+Treg cells were determined by flow cytometry. Results : The cell numbers of CD4+CD25+Treg cell subsets were markedly increased in PT treated mice as reported. However, PT significantly reduced the CD3+CCR3+ Th2 cells in PBMC and lung of mice. Conclusions : These results indicate that PT has a deep inhibitory effect on asthma model mice by increase the number of regulatory T cells, and by reducing CD3+CCR3+ Th2 cells.

• Fisheries and Aquatic Sciences
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• 제8권2호
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• pp.56-64
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• 2005

Two distinct CD3 homologue genes, $CD3\gamma/\delta\;and\;CD\varepsilon$, were isolated from a olive flounder leukocyte cDNA library and a BAC library. $CD3\gamma/\delta$ consisted of 961 bp encoding 178 amino acid residues, and $CD3\varepsilon$ consisted of 1006 bp encoding 164 amino acid residues. When compared with other known CD3 peptide sequences, the most conserved region of the two olive flounder CD3 chain peptides are the cytoplasmic domain and the least conserved are the extracellular domain. A phylogenetic analysis based on the deduced amino acid sequence grouped the two olive flounder CD3 sequences with $CD3\varepsilon$ and $CD3\gamma/\delta$, respectively. The olive flounder CD3 cluster (consisting of $CD3\varepsilon\;and\;CD3\gamma/\delta$) spans only 10.4 kb. The $CD3\varepsilon\;and\;CD3\gamma/\delta$ genes are oppositely transcribed only 3.8 kb apart. Both olive flounder CD3 genes have five exons. The two olive flounder CD3 genes were predominantly expressed in PBLs, kidney, spleen, and gills.