• Environmental Analysis Health and Toxicology
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• v.17 no.4
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• pp.325-332
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• 2002

A helper T(Th)1-mediated response is known to enhance cell -mediated immunity, while a Th2-mediated response is associated with the humoral immunity that if elevated IgE levels and eosinophilia. Prostaglandin (PG)E$_2$results in the decreased capability of Iymphocytes to produce Thl cytokines, with a shift toward a Th2 cytokine response. Chlorpyrifos (CPF) has been reported to impair the blastogenesis and response of T Iymphocytes. CPF also induces delayed febrile effects, which results from the activation of COX -PGE$_2$pathway. The purpose of this study is to determine the effort of CPF on the in vitro production of Th cytokines and the role of PGE$_2$on the CPF-induced production of Th cytokines. Splenocytes obtained from male BALB/c mice were pretreated with CPF(0.1, 1, 10 and 100$\mu$M) in the presence of absence of indomethacin or PGE$_2$for 12 h and then were incubated with concanavalin (Con) A for 48 h. These results showed that CPF remarkedly reduced the production of splenic interleukin (IL)-2 and interferon (IFN)-γ in a dose-dependent manner. CPF significantly increased the splenic IL-4 production at low doses (0.1 and 1$\mu$M) but did not affect at high doses (10 and 100 $\mu$M). Indomethacin reduced the CPF-decreased production of IL-2 and IFN-γ in a dose -dependent manner and significantly attenuated the production of IL-4 increased by CPF 0.1 $\mu$M. High dose of CPF significantly reduced the PGE$_2$-decreased production of IL-2 and IFN-γ, while the PGE$_2$- induced production of IL-4 was significantly enhanced by CPF 1 $\mu$M. These findings suggest that CPF nay down-regulate the immune response of Th 1 type by the suppressed production of IL-2 and IFN-γ, with a shift toward a Th2 cytokine response. The CPF-decreased production of Thl cytokines may not be mediated by endogenous PGE$_2$. Also, CPF may attenuate the exogenous PGE$_2$-decreased Th 1 immune response in a dose--dependent manner but may affect dose-independently the PGE$_2$-induced Th2 immune response.

• YAKHAK HOEJI
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• v.48 no.6
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• pp.369-373
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• 2004

We previously reported that Streptococcus pneumoniae capsule attached to the surface protein (JY-Pol) was protective to systemic pneumococcal infection. The JY -Pol antigen induced IgM, IgG, and IgA in mice and provoked cell-mediated immunity. In this current study, we investigated the effect of anti JY-Pol antiserun and monoclonal antibody C2 (Mab C2) specific for the JY-Pol antigen against the pneumococcal disease. Mice that were given the antiserum survived longer than mice that received antiserum pre-absorbed with S.pneumoniae cells or DPBS as a negative control. Heat-treated anti JY-Pol antiserum resulted in survival rates similar to intact fresh JY-Pol antiserum. Mab C2 isolated from JY-Pol-immunized mice also enhanced resistance of naive mice against the pneumococcal diseaser. This protection by Mab C2 appeared to be mediated by opsonization as determined in a RAW 264.7 monocyte/macrophage cell line. Epitope analysis showed that Mab C2 epitope consisted of glucuronic acid and glucose that blocked the interaction of JY-Pol to the C2. Taken together, these data indicate that the antiserum induced by the JY-Pol, a naturally pneumococcal conjugate formula, mediated the protection by passive transfer, which was confirmed by protective effect of Mab C2.

• IMMUNE NETWORK
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• v.6 no.4
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• pp.185-191
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• 2006

Background: Based on outstanding progresses in animal experiments, vaccines for some human tumors have been developed. However, clinical effects of these vaccines have been far below than expected. This discrepancy might come from differences between animal models and human patients with respect to immunocompetency. The immune status of mice after tumor inoculation has not been well studied, which make us cautious in interpreting and applying the results from mice to human. We evaluated cell-mediated immune responses in mice after tumor cell inoculation. Methods: Mice were inoculated with TA3Ha, CT26, or 4T1. Delayed-type hypersensitivity (DTH) responses were induced 2-4 weeks after inoculation using 2,4-dinitro-1-fluorobenzene as an antigen. The relationships between the severity of DTH responses and the duration of tumor inoculation or the size of tumor mass were analyzed. Results: In T A3Ha groups, DTH response was elevated 2 weeks after inoculation, but depressed after 4 weeks, compared to the control group. When analyzed based on the sizes of tumor masses elicited, DTH responses were inversely related to the mass size, especially in those greater than 10 mm in diameter. In CT26 groups, while the duration after inoculation did not affect the severity of DTH responses, those with large mass showed depressed responses regardless the duration of inoculation. 4T1 cells grew so slowly that the size of tumor mass was small even 4 weeks after inoculation, and this group showed much higher DTH responses compared to that of tumor-free group. Conclusion: At least in an experimental setting where tumor model was induced by inoculating tumor cell lines into immunologically competent mice, the host immune response was elevated in early stage, and then depressed in late stage when the mass grew over a critical size.

• IMMUNE NETWORK
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• v.6 no.2
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• pp.102-110
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• 2006

Background: Dendritic cells (DC) are professional antigen-presenting cells in the immune system and can induce T cell response against virus infections, microbial pathogens, and tumors. Therefore, immunization using DC loaded with tumor-associated antigens (TAAs) is a powerful method of inducing anti-tumor immunity. For induction of effective anti-tumor immunity, antigens should be efficiently introduced into DC and presented on MHC class I molecules at high levels to activate antigen-specific $CD8^+$ T cells. We have been exploring methods for loading exogenous antigens into APC with high efficiency of Ag presentation. In this study, we tested the effect of the cationic liposome (Lipofectin) for transferring and loading exogenous model antigen (OVA protein) into BM-DC. Methods: Bone marrow-derived DC (EM-DC) were incubated with OVA-Lipofectin complexes and then co-cultured with B3Z cells. B3Z activation, which is expressed as the amount of ${\beta}$-galactosidase induced by TCR stimulation, was determined by an enzymatic assay using ${\beta}$-gal assay system. C57BL/6 mice were immunized with OVA-pulsed DC to monitor the in vivo vaccination effect. After vaccination, mice were inoculated with EG7-OVA tumor cells. Results: BM-DC pulsed with OVA-Lipofectin complexes showed more efficient presentation of OVA-peptide on MHC class I molecules than soluble OVA-pulsed DC. OVA-Lipofectin complexes-pulsed DC pretreated with an inhibitor of MHC class I-mediated antigen presentation, brefeldin A, showed reduced ability in presenting OVA peptide on their surface MHC class I molecules. Finally, immunization of OVA-Lipofectin complexes-pulsed DC protected mice against subsequent tumor challenge. Conclusion: Our data provide evidence that antigen-loading into DC using Lipofectin can promote MHC class I- restricted antigen presentation. Therefore, antigen-loading into DC using Lipofectin can be one of several useful tools for achieving efficient induction of antigen-specific immunity in DC-based immunotherapy.

• Journal of Nutrition and Health
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• v.43 no.2
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• pp.152-160
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• 2010

The purpose of this study was to investigate the effects of aging process on the immunity in human subjects. In this investigation, nineteen families of three generations (daughters on college age, their mothers, and grandmothers) participated to avoid genetic variation among individuals. Dietary food records, anthropometric measurements and biochemical assessments of serum nutrients were used to evaluate the nutritional status of subjects. The immune parameters of subjects were assessed by the total and differential WBC count. Total B and T lymphocytes, and T cell subsets were quantified by flowcytometer. Serum immunoglobulin G, A, M concentrations were also measured as an index of humoral immunity. The result of this study can be summarized as follows: 1. Along with the aging process, body fat was found to be increased whereas lean body mass and total body water were diminished. Since there were no significant difference in serum vitamin E levels in all age groups, serum retinal concentrations tended to decrease as one gets old. 2. Although total number of T lymphocytes seemed to be unchanged, B lymphocytes and NK cell numbers were increased by aging. The Percentage of CD8 + lymphocytes was lower in the elderly subjects compared with the younger, resulting in higher ratio of CD4 +/CD8 + lymphocytes in the elderly. Serum Ig G and Ig A levels remained unchanged, but IgM levels were significantly decreased as the age processes continue. Taking all together, it could be suggested that the alteration of immune cell population by aging is selective and possibly nonage factors such as nutrition may be attributable to the change of immunity in the elderly. The nutritional status and aging process may selectively affect both the cell-mediated (CD8 +, CD4 + CD8 + ratio, NK cell) and humoral (B lymphocyte, Immunoglobulin M, G) immune parameters in human subjects.

• IMMUNE NETWORK
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• v.11 no.4
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• pp.210-215
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• 2011

It is already known that high concentration of vitamin C induces apoptosis on tumor cells. However, there is no report regarding the function of vitamin C on the modulation of immune susceptibility of cancer. Therefore, we investigated whether vitamin C can modulate immune susceptibility of tumor cells, especially on the induction of Fas-mediated apoptosis. First, the optimal concentration of vitamin C, which cannot induce damages on tumor cells for 36 hrs. We found that 2 mM of vitamin C did not show harmful effect. In addition, the optimal concentration of agonistic anti-Fas Abs for 18 hrs was examined. As a result, 400 ng/ml of agonistic anti-Fas Abs did not induce apoptosis on tumor cells. Next, we tried to find the effect of 2 mM of vitamin C on the modulation of the susceptibility to agonistic anti-Fas Abs. When tumor cells were cultured with 400 ng/ml of agonistic anti-Fas Abs for 18 hrs, after pre-treatment with 2 mM of vitamin C for 24 hrs, viability of cells was decreased. Interestingly, we found that the expression of Fas (CD95) and MHC class I was increased by the treatment of vitamin C. Taken together, vitamin C increases the susceptibility of tumor cells to anti-Fas Abs and the expression of Fas (CD95) and MHC class I on tumor cells.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.26-26
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• 2015

Phytophthora infestans is the causal agent of potato and tomato late blight, one of the most devastating plant diseases. P. infestans secretes effector proteins that are both modulators and targets of host plant immunity. Among these are the so-called RXLR effectors that function inside plant cells and are characterized by a conserved motif following the N-terminal signal peptide. In contrast, the effector activity is encoded by the C terminal region that follows the RXLR domain. Recently, I performed in planta functional profiling of different RXLR effector alleles. These genes were amplified from a variety of P. infestans isolates and cloned into a Potato virus X (PVX) vector for transient in planta expression. I assayed for R-gene specific induction of hypersensitive cell death. The findings included the discovery of new effector with avirulence activity towards the Solanum bulbocastanum Rpi-blb2 resistance gene. The Rpi-blb2 encodes a protein with a putative CC-NBS-LRR (a coiled-coil-nucleotide binding site and leucine-rich repeat) motif that confers Phytophthora late blight disease resistance. We examined the components required for Rpi-blb2-mediated resistance to P. infestans in Nicotiana benthamiana. Virus-induced gene silencing was used to repress candidate genes in N. benthamiana and to assay against P. infestans infections. NbSGT1 was required for disease resistance to P. infestans and hypersensitive responses (HRs) triggered by co-expression of AVRblb2 and Rpi-blb2 in N. benthamiana. RAR1 and HSP90 did not affect disease resistance or HRs in Rpi-blb2-transgenic plants. To elucidate the role of salicylic acid (SA) in Rpi-blb2-mediated resistance, we analyzed the response of NahG-transgenic plants following P. infestans infection. The increased susceptibility of Rpi-blb2-transgenic plants in the NahG background correlated with reduced SA and SA glucoside levels. Furthermore, Rpi-blb2-mediated HR cell death was associated with $H_2O_2$, but not SA, accumulation. SA affects basal defense and Rpi-blb2-mediated resistance against P. infestans. These findings provide evidence about the roles of SGT1 and SA signaling in Rpi-blb2-mediated resistance against P. infestans.

• The Journal of the Korean Society for Microbiology
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• v.16 no.1
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• pp.65-70
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• 1981

A microculture technique for the mixed lymphocyte culture test(MLC) in the sheep is described. The optimal incubation periods for the MLC are varied from 4 to 6 days depending on the sources of lymphocytes. It is found that a 2.5:1 stimulator-responder cell ratio and the responder cell concentration of $1{\times}10^5$ cells/well produce the highest($^3H$)-thymidine incorporation. Moreover cryopreservation of bovine lymphocytes results in satisfactory and reproducible MLC reaction. It is also evident that the MLC reactions of the sheep are under the control of histocompatibility matching between the stimulator cells and the responder cells. Significance of the technique as a too! for study on cell mediated immunity in sheep system, either normal or squamous cell carcinoma-bearing, are discussed.

• Animal cells and systems
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• v.12 no.3
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• pp.127-136
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• 2008

Caspase-11 has been known as a dual regulator of cytokine maturation and apoptosis. Although the role of caspase-11 under pathological conditions has been well documented, its physiological role has not been studied much. In the present study, we investigated a possible physiological function of caspase-11 during immune response. In the absence of caspase-11, immunized spleen displayed increased cellularity and abnormal germinal center structure with disrupted microarchitecture. The rate of cell proliferation and apoptosis in the immunized spleen was not changed in the caspase-11-deficient mice. Furthermore, the caspase-11-deficient peritoneal macrophages showed normal phagocytotic activity. However, caspase-11-/-splenocytes and macrophages showed defective migrating capacity. The dysregulation of cell migration did not seem to be mediated by caspase-3, interleukin-$1{\alpha}$ or interleukin-$1{\beta}$ which acts downstream of caspase-11. These results suggest that a direct regulation of immune cell migration by caspase-11 is critical for the formation of germinal center microarchitecture during immune response. However, humoral immunity in the caspase-11-deficient mice was normal, suggesting the formation of germinal center structure is not essential for the affinity maturation of the antibodies.

• Journal of Korean Port Research
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• v.13 no.2
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• pp.389-398
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• 1999

In the biological immunity, the immune system of organisms regulates the antibody and T-cells to protect the attack from the foreign materials which are virus, germ cell, and other antigens, and supports their stable state. It has similar characteristics that has the adaptation and robustness to overcome disturbances and to control the plant of engineering application. In this paper, we build a model of the T-cell regulated immune response mechanism. We have also designed an immune response controller(IRC) focusing on the T-cell regulated immune response of the biological immune system that include both a help part to control the response and a suppress part to adjust system stabilization effect. We show some computer simulation to control the vibration of building structure system with strong wind forces excitation also demonstrate the efficiency of the proposed controller for applying a practical system even with existing nonlinear terms.