• Toxicological Research
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• v.18 no.3
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• pp.227-232
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• 2002

In order to find out the appropriate in vitro method for high correlation with in vivo, we com-pared the sensitivities of phototoxicity (PT) in vitro method between in human keratinocytes, HaCaT cells and in 3T3 fibroblast cells derived from Balb/c mice. Both cells were exposed to six known phototoxic chemicals : promethazine, neutral red, chlortetracycline, amiodarone, bithionol, 8-methoxypsoralen, or non-phototoxic chemical, ALS (ammonium laureth sulfate) and then irradiated with 5 J/$cm^2$ of UVA. Cell viability ($IC_{50}$ ) was measured by neutral red uptake (NRU) assay. The ratio of $IC_{50}$ value of chemicals in the presence and absence of UVA was determined by the cut-off value. The phototoxic potential of test chemicals in NRU assay was determined by measuring the photoirriation factor (PIF) with a cut-off value of 5. In both 3T3 and HaCaT cells, all known phototoxic chemicals were positive (over 5 of PIF value), except that bithionol was found to be non-phototoxic to HaCaT cells, and ALS, non-phototoxic chemical was negative. These results suggest that Balb/c 3T3 cell was more sensitive than HaCaT cell to predict phototoxicity potential.

• Journal of IKEEE
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• v.16 no.3
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• pp.265-273
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• 2012

Data stability and leakage power dissipation have become a critical issue in scaled SRAM design. In this paper, an advanced 8T SRAM cell improving the read and write stability of data storage elements as well as reducing the leakage current in the idle mode is presented. During the read operation, the bit-cell keeps the noise-vulnerable data 'low' node voltage close to the ground level, and thus producing near-ideal voltage transfer characteristics essential for robust read functionality. In the write operation, a negative bias on the cell facilitates to change the contents of the bit. Unlike the conventional 6T cell, there is no conflicting read and write requirement on sizing the transistors. In the standby mode, the built-in stacked device in the 8T cell reduces the leakage current significantly. The 8T SRAM cell implemented in a 130 nm CMOS technology demonstrates almost 100 % higher read stability while bearing 20 % better write-ability at 1.2 V typical condition, and a reduction by 45 % in leakage power consumption compared to the standard 6T cell. The stability enhancement and leakage power reduction provided with the proposed bit-cell are confirmed under process, voltage and temperature variations.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1021-1027
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• 2004

Panax ginseng has been used as a typical tonic medicine in Asian countries, such as Korea, China, and Japan. It has been reported that ginsenoside Rg1 in Panax ginseng increases the proportion of T helper cells in the whole T cells and promotes IL-2 gene expression in murine splenocytes. These studies imply that ginsenoside Rg1 increases the immune activity of CD4+ T cell, however the exact mechanism of ginsenoside Rg1 on helper T cell remains to be verified. The present study tried to elucidate the direct effect of Rg1 on helper T cell s activities and its Th1/Th2 lineage development. The results demonstrated that ginsenoside Rg1 had not mitogenic effects on the unstimulated CD4+ T cell, but augmented CD4+ T cell proliferation upon activating with anti-CD3/anti-CD28 antibodies in a dose dependent manner. Rg1 also enhanced the expression of cell surface protein CD69 on CD4+ T cell. In Th0 condition, ginsenoside Rg1 increases the expression of IL-2 mRNA, and enhances the expression of IL-4 mRNA on CD4+ T cells, suggesting Rg1 prefer to induce Th2 lineage development. In addition, ginsenoside Rg1 increases IL-4 secreting CD4+ T cell under Th2 skewed condition, while decreases IFN-γ secreting cell in Th1 polarizing condition. Thus, Rg1 enhances Th2 lineage development from naive CD4+ T cell both by increasing Th2 specific cytokine secretion and by repressing Th1 specific cytokine production. Therefore, these results suggest that ginsenoside Rg1 might be desirable agent for enhancing CD4+ T cell's activity, as well as the correction of Th1 dominant pathological disorders.

• Molecules and Cells
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• v.26 no.1
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• pp.67-73
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• 2008

Herpetic stromal keratitis (HSK) is an inflammatory disorder induced by HSV-1 infection and characterized by T cell-dependent destruction of corneal tissues. It is not known what triggers $CD4^+$ T cell migration into the stroma of HSV-1-infected corneas. The keratocyte is a fibroblast-like cell that can function as an antigen-presenting cell in the mouse cornea by expressing MHC class II and costimulatory molecules after HSV-1 infection. We hypothesized that chemokines produced by stromal keratocytes are involved in $CD4^+$ T cell infiltration into the cornea. We found that keratocytes produce several cytokines and chemokines, including MCP-1, RANTES, and T cell activation (TCA)-3. HSV-1 infection increased the production of MCP-1 and RANTES by keratocytes, and these acted as chemoattractants for HSV-1-primed $CD4^+$ T cells expressing CCR2 and CCR5. ExpreHerpetic stromal keratitis (HSK) is an inflammatory disorder induced by HSV-1 infection and characterized by T cell-dependent destruction of corneal tissues. It is not known what triggers $CD4^+$ T cell migration into the stroma of HSV-1-infected corneas. The keratocyte is a fibroblast-like cell that can function as an antigen-presenting cell in the mouse cornea by expressing MHC class II and costimulatory molecules after HSV-1 infection. We hypothesized that chemokines produced by stromal keratocytes are involved in $CD4^+$ T cell infiltration into the cornea. We found that keratocytes produce several cytokines and chemokines, including MCP-1, RANTES, and T cell activation (TCA)-3. HSV-1 infection increased the production of MCP-1 and RANTES by keratocytes, and these acted as chemoattractants for HSV-1-primed $CD4^+$ T cells expressing CCR2 and CCR5. Expression of MCP-1 in the corneal stroma was confirmed in vivo. Finally, when HSV-1-primed $CD4^+$ T cells were adoptively transferred into wild type and MCP-1-deficient mice that had been sublethally irradiated to minimize chemokine production from immune cells, infiltration of $CD4^+$ T cells was markedly reduced in the MCP-1-deficient mice, suggesting that it is the MCP-1 from HSV-1-infected keratocytes that attracts $CD4^+$ T cells into the cornea.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.1
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• pp.153-163
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• 1996

Macrophage inflammatory protein $(MIP)-1{\alpha}$ is a cytokine which produces wide range of bioactivities such as proinflammatory, immunomodulatory, and hematopoietic modulatory actions. To determine whether $MIP-1{\alpha}$ acts as a negative regulator on the functions of lymphocyte, $[^3H]$-thymidine incorporation test and flow cytometric analysis were performed by using human tonsil T cell, human peripheral blood T cell, and murine cytolytic T lymphocyte (CTL) line CTLL-2, The results were as follow. 1. When human tonsil T lymphocytes were stimulated with anti-CD3 monoclonal antibody (mAb), rate of T cell proliferation was about four times increased. 200ng/ml of $MIP-1{\alpha}$ inhibited anti-CD3 mAb-mediated T cell growth as much as 60% (P<0.05). 2. The suppression of human peripheral T cell proliferation produced by $MIP-1{\alpha}$ was dramatic, but variable among T cells derived from different individuals $(40%{\sim}90%)$. 3. $MIP-1{\alpha}$inhibited the proliferation of murine CTL line CTLL-2 as much as 75%(P<0.001). 4. When the $MIP-1{\alpha}$ was added to human peripheral T cell, cell proporation of $CD4^+$ helper T cell and $CD8^+$ CTL were not noticeably affected. The expression level of CD4, not of Cd8, however, was down regulated by $MIP-1{\alpha}$ treatment $(27%{\sim}82%)$.

• Journal of Life Science
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• v.25 no.6
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• pp.686-692
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• 2015

Cancer is subject to dynamic interactions between contrary immune reactions that drive both tumor growth and suppression. Forkhead box p3 positive T cells (Foxp3 positive T cells) might support tumor promotion, while CD8 positive T cells might protect the host. The present study examined the distributions of CD8- and Foxp3-positive T cells and CD8 positive T cells/ Foxp3 positive T cells ratio in skin squamous cell carcinoma (SCC) and its precancerous lesions; it also compared this with data for basal cell carcinoma (BCC). Iimmunohistochemical staining for CD8 and Foxp3 was conducted in 20 cases of SCC, Bowen's disease (BD), actinic keratosis (AK) and BCC. The BD and SCC cases exhibited significantly increased numbers of both CD8- and Foxp3-positive T cells in their advancing regions compared with the AK and BCC cases, and the BD cases exhibited significantly lower CD8 positive T cells / Foxp3 positive T cells ratio in these regions than did the AK and BCC cases. There was no significant difference in both T cells and the ratio between BD and SCC. The degree of both T cells infiltration differed between the advancing and central areas in SCC and BCC. Immune micro-environments differ between cutaneous squamous cell tumors and BCC and differ as well among tumor compartments.

• Herbal Formula Science
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• v.5 no.1
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• pp.169-178
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• 1997

To investigate effect of water extract of Asparagi Tuber(天門冬) on human cancer cell-lines and immunocytes, this research estimated proliferation of A431 cell line, KHOS-NP cell line, mouse thymocytes and mouse splenocytes, Nitric Oxide(NO) from macrophage, apoptosis and subpopulation of the mouse thymocytes. The result were obtained as follows ; 1. Asparagi Tuber inhibited the proliferation of A431 cell line. 2. Asparagi Tuber inhibited the proliferation of KHOS-NP cell line. 3. Asparagi Tuber accelerated the proliferation of mouse thymocytes. 4. Asparagi Tuber inhibited the proliferation of mouse splenocytes. 5. Asparagi Tuber $100{\mu}g/m{\ell}$ inhibited the production of NO from macrophages in vitro, being compared NPS+IFN treated group. 6. Asparagi Tuber inhibited the production of NO from macrophages in vivo, being compared LPS+IFN treated group. 7. Asparagi Tuber accelerated the induction of apoptosis of the mouse thymocytes. 8. In subpopulation Asparagi Tuber increased $T_H$ of the mouse thymocytes, but decreased $T_C/T_S$ of the mouse thymocytes.

• Biomolecules & Therapeutics
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• v.4 no.2
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• pp.148-153
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• 1996

Activation of the T lymphocytes results in a variety of early biochemical events ultimately leading to cell proliferation and lymphokine production. Stimulation of the signal transduction cascade in T cells through the T cell receptor coincides with activation of the phosphatidylinositol-phospholipase C (PI-PLC) pathway. Therefore, we have established a model system to screen immune-simulator that can increase the hydrolysis of phosphoinositides in human T cell leukemia Jurkat cells. As a result of screening from herbal medicine extract, 4 extracts (O1ibanum, Ephedrae Herba, Real Gar, Saussureae Radix) were found 14 increase the production of inositol phosphates. All the active fraction from the four kinds of extract were fluted in a different retention time on C-18 HPLC and these active fraction also showed difference in cell specificity. And all the active fractions increased DNA synthesis in T cell. Therefore, it is suggested that the active fraction among 4 extracts might contain a compound having different properties one another.

• IMMUNE NETWORK
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• v.22 no.1
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• pp.6.1-6.19
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• 2022

Chimeric antigen receptor (CAR) T cells, which express a synthetic receptor engineered to target specific antigens, have demonstrated remarkable potential to treat haematological malignancies. However, their transition beyond haematological malignancy has so far been unsatisfactory. Here, we discuss recent challenges and improvements for CAR T cell therapy against solid tumors: Antigen heterogeneity which provides an effective escape mechanism against conventional mono-antigen-specific CAR T cells; and the immunosuppressive tumor microenvironment which provides physical and molecular barriers that respectively prevent T cell infiltration and drive T cell dysfunction and hypoproliferation. Further, we discuss the application of CAR T cells in infectious disease and autoimmunity.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.4 no.1
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• pp.111-129
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• 1998

In order to research the effect of Sipjundaebotang on the immune respons of CD4+ T cell and CD8+ T cell in rats, author have performed this experimental study. Experimental groups are divided into 5 groups(intact, control, sample I, sample II, sample III). Normal group was intact, control group was administrated normal saline 2cc for 5 days, sample I was administrated low concentration of Sipjundaebotang(100/3100pack/ml) 2cc for 5 days, sample II was administrated middle concentration of Sipjundaebotang(500/3100pack/ml) 2cc for 5 days, sample III was administrated high concentration of Sipjundaebotang(2500/3100pack/ml) 2cc for 5 days. WBC, Lymphocyte, CD4+ T cell in the blood, spleen, axillary node and CD8+ T cell in the blood, spleen and axillary node were determined. The results was as follows: 1. WBC count in blood was significantly decrcased in the control, sample I, II, III groups as compared with the normal group. 2. Lymhocyte count in the blood was significantly decreased in the control, sample I, II groups as compared with the normal group. 3. CD4+ T cell count in the blood was significantly increased dose-dependently in the sample I, II, III groups as compared with the normal group. 4. CD4+ T cell count in the spleen was significantly increased in the sample I, II, III groups as compared with the normal group. 5. CD4+ T cell count in the axillary node was significantly increased in the sample III group as compared with the normal group, however significantly decreased in the sample I, II groups as compared with the normal group. 6. CD8+ T cell count in the blood was significantly increased in the sample III groups as compared with the normal group. 7. CD8+ T cell count in the spleen was significantly increased in the sample I, II, III groups as compared with the normal group. but there was no differences in the sample groups. 8. CD8+ T cell count in the axillary node was decreased in the sample I, II groups as compared with the normal group.