• Journal of Nutrition and Health
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• 제27권2호
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• pp.153-161
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• 1994

We fed high trypotophan diet(3.5% tryptophan/diet(w/w) to mice for 7 days and treated then with 3 hour immobilization(IMMB) stress to investigate tryptophan metabolism and immunomodulation. The levels of serum tryptophan, brain tryptophan, serotonin(5HT) and 5-hydroxyindoleacetic acid(5HIAA) in the tryptophan diet fed animals were higher than those of the normal diet fed animals. Feeding tryptophan supplemented diet to stressed animal significantly decreased the levels of serum and brain tryptophan and 5HT levels. However, the amount of 5HIAA which is the metabolite of serotonin was increased in brain. Plasma corticosterone level was increased by the stress in both groups but the degree of this increase was smaller in high tryptophan fed animals. The relative numbers of CD8+ T cells, CD4+ T cells and B cells in spleen were decreased in high tryptophan diet fed and stressed animals compared to control diet fed and no stressed animals. CD8+ T cells decreased more than CD4+ T cells. The decrease of CD8+ T cells in high tryptophan fed and stressed animals was similar to that in high tryptophan fed animals or normal diet fed and stressed animals. Stress and tryptophan supplement acted synergistically to decrease the number of B cells. This study suggests that stress and tryptophan supplement could modify the number of lymphocyte cells, and indicates that the interaction of stress and tryptophan supplement on immune fuction depends on the types of immune cells.

• 대한수의학회지
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• 제34권3호
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• pp.441-446
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• 1994

serum factor가 $CD8^+$ T cell의 lymphokine 생산양상에 미치는 영향을 알아보기 위하여 13-20주령의 BAL B/C 마우스로 부터 $CD8^+$ T cell를 분리한 후 serum-containing medium과 serum-free medium을 사용하여 배양하였다. serum-free medium에서 배양한 $CD8^+$ T cell이 분비하는 lymphokine의 양은 serum-containg medium에서의 결과와는 달리 IL-2의 생산양은 낮았으나 IFNr의 생산양은 상당히 높았다. 이와같은 결과로 미루어 serum-derived factor가 $CD8^+$ T cell의 lymphokine 생산에 영향을 미친다고 생각된다.

• IMMUNE NETWORK
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• 제3권3호
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• pp.235-241
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• 2003

Background: The protective immunity against tuberculosis (TB) involves both CD4+ T cells and CD8+ T cells. In our previous study, we defined four Mycobacterium tuberculosis derived peptide epitopes specific for HLA-$A^*0201$ restricted CD8+ T cells ($ThyA_{30-38}$, $RpoB_{127-135}$, $85B_{15-23}$, $PstA1_{75-83}$). In this study, we investigated the immune responses induced by these peptide specific CD8+ T cells in latently and chronically infected people with TB. Methods: We characterized these peptide specific CD8+ T cell population present in PBMC of both TB patients and PPD+healthy people using IFN-${\gamma}$elispot assay, intracellular staining and HLA-A2 dimer staining. Results: The frequency of peptide specific CD8+ T cell was in the range of 1 to 25 in $1.7{\times}10^5$ PBMC based on ex vivo IFN-${\gamma}$ elispot assay, demonstrating that these peptide specific CD8+ T cell responses are induced in both TB patients and PPD+ people. Short term cell lines (STCL) specific for these peptides proliferated in vitro and secreted IFN-${\gamma}$ upon antigenic stimulation in PPD+ donors. Lastly, HLA-$A^*0201$ dimer assays indicated that $PstA1_{75-83}$ specific CD8+ T cell population in PPD+ healthy donors is heterogeneous since approximately 25~33% of $PstA1_{75-83}$ specific CD8+ T cell population in PPD+ healthy donors produced IFN-${\gamma}$ upon peptide stimulation. Conclusion: Our results suggest that MHC class I restricted CD8+ T cell mediated immune responses to M. tuberculosis infection are induced in both TB patients and PPD + people; however, the CD8+ T cell population is functionally heterogeneous.

• KSBB Journal
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• 제17권6호
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• pp.520-524
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• 2002

초석잠의 항암효과 및 면역조절자로서의 기능을 알아보기 위하여 마우스를 이동하여 실험한 결과, 마우스 비장세포의 증식반응은 항진시켰으나 YAC-1 세포주의 증식능은 억제시켰다. CD4+ T세포 및 CD8+ T세포의 비율이 정상 대조군 마우스의 그것에 비하여 증가하였으나 CD4+/CD8+ 비는 차이가 없었으며 비장세포에서 IL-2수용체의 발현이 항진되었다. 또한, 복강대식세포로부터의 nitric oxide와 TNF-$\alpha$ 생산을 항진시켰으며, 복강대식세포는 탐식능이 현저하게 항진되었고 B16F10 흑색종의 폐전이가 억제됨을 알 수 있었다. 따라서, 초석잠의 항암제 및 면역반응 조절자로서의 개발 가능성이 있음을 시사한다.

• Journal of Microbiology and Biotechnology
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• 제16권6호
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• pp.911-920
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• 2006

[ $CD8^+$ ] T Iymphocytes with the cytotoxic activity and capability to release various cytokines are the major players in immune responses against viral infection and cancer. To identify the proteins specific to resting or activated human CD8$^+$ T cells, human CD8$^+$ T cells were activated with anti-CD3+anti-CD28 mAb in the presence of IL-2. The solubilized proteins from resting and activated human CD8$^+$ T cells were separated by high-resolution two-dimensional polyacrylamide gel electrophoresis, and their proteomes were analyzed. Proteomic analysis of resting and activated T cells resulted in identification of 35 proteins with the altered expression. Mass spectrometry coupled with Profound and SWISS-PROT database analysis revealed that these identified proteins are to be functionally associated with cell proliferation, metabolic pathways, antigen presentation, and intracellular signal transduction pathways. We also identified six unknown proteins predicted from genomic DNA sequences specific to resting or activated CD8$^+$ T cells. Protein network studies and functional characterization of these novel proteins may provide new insight into the signaling transduction pathway of CD8$^+$ T cell activation.

• Parasites, Hosts and Diseases
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• 제40권3호
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• pp.119-129
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• 2002

Although there are many reports on the splenic (systemic) T cell response after Toxoptasma gondii infection, little information is available regarding the local T cell responses of peritoneal exudate cells (PEC) and gut intraepithelial Iymphocytes (IEL) following peroral infection with bradyzoites. Mice were infected with 40 cysts of the 76K strain of T. gondii, and then sacrificed at days 0, 1, 4, 7 and 10 postinfection (PI). The cellular composition and T cell responses of PEC and IEL were analyzed. The total number of PEC and IEL per mouse increased after infection, but the ratio of increase was higher in IEL. Lymphocytes were the major component of both PEC and IEL. The relative percentages of PEC macrophages and neutrophils/eosinophils increased signiflcantly at day 1 and 4 PI, whereas those of IEL did not change significantly. The percentage of PEC NK1.1 and ${\gamma\delta}T$ cells peaked at day 4 PI (p < 0.0001), and CD4 and $CD8{\alpha}T$ cells increased continuously after infection. The percentages of IEL $CD8{\alpha}$ and ${\gamma\delta}T$ cells decreased slightly at first, and then increased. CD4 and NK1.1 T cells of IEL did not change significantly after infection. $IFN-{\gamma}-producing$ PEC NK1.1 T cells increased significantly from day 1 PI, but the other T cell subsets produced $IFN-{\gamma}$ abundantly thereafter. The proportion of IEL $IFN-{\gamma}-producing$ $CD8{\alpha}$ and ${\gamma\delta}T$ cells increased significantly after infection, while IEL NK1.1 T cells had similar $IFN-{\gamma}$ production patterns. Taken together, CD4 T cells were the major phenotype and the important $IFN-{\gamma}$ producing T cell subsets in PEC after oral infection with T. gondii whereas $CD8{\alpha}T$ cells had these roles in IEL. These results suggest that PEC and IEL comprise different cell differentials and T cell responses, and according to infection route these factors may contribute to the different cellular immune responses.

• Tuberculosis and Respiratory Diseases
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• 제86권4호
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• pp.304-318
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• 2023

Background: Cancer-associated fibroblasts (CAFs) are key components of the tumor microenvironment and significantly contribute to immune evasion. We investigated the effects of CAFs on the immune function of CD4+ and CD8+ T cells in non-small cell lung cancer (NSCLC). Methods: We isolated CAFs and normal fibroblasts (NFs) from tumors and normal lung tissues of NSCLC patients, respectively. CAFs were co-cultured with activated T cells to evaluate their immune regulatory function. We investigated the effect of CAF conditioned medium (CAF-CM) on the cytotoxicity of T cells. CAFs were also co-cultured with activated peripheral blood mononuclear cells and further incubated with cyclooxygenase-2 (COX2) inhibitors to investigate the potential role of COX2 in immune evasion. Results: CAFs and NFs were isolated from the lung tissues (n=8) and lymph nodes (n=3) of NSCLC patients. Immune suppressive markers, such as COX2 and programmed death-ligand 1 (PD-L1), were increased in CAFs after co-culture with activated T cells. Interestingly, CAFs promoted the expression of programmed death-1 in CD4+ and CD8+ T cells, and strongly inhibited T cell proliferation in allogenic and autologous pairs of CAFs and T cells. CAF-CM decreased the cytotoxicity of T cells. COX2 inhibitors partially restored the proliferation of CD4+ and CD8+ T cells, and downregulated the expression of COX2, prostaglandin E synthase, prostaglandin E2, and PD-L1 in CAFs. Conclusion: CAFs promote immune evasion by suppressing the function of CD4+ and CD8+ T cells via their effects on COX2 and PD-L1 in NSCLC. The immunosuppressive function of CAFs could be alleviated by COX2 inhibitors.

• IMMUNE NETWORK
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• 제8권2호
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• pp.46-52
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• 2008

Background: Oral tolerance is defined by the inhibition of immune responsiveness to a protein previously exposed via the oral route. Protein antigens exposed via the oral route can be absorbed through the mucosal surfaces of the gastrointestinal tract and can make physical contact with immune cells residing in the intestinal lamina propria (LP). However, the mechanisms of oral tolerance and immune regulation in the intestines currently remain to be clearly elucidated. Methods: In order to determine the effect of oral protein antigen intake (ovalbumin, OVA) on the intestinal LP, we assessed the expression profile of the T cell receptor and the co-receptors on the cells from the intestines of the tolerant and immune mouse groups. Results: We determined that the proportion of OVA-specific B cells and ${\gamma}{\delta}$ T cells had decreased, but the CD8${\alpha}{\beta}$ and D8${\alpha}{\alpha}$ T cells were increased in the LP from the tolerant group. The proportion of CD8＋ T cells in the spleen did not evidence any significant differences between treatment groups. Conclusion: These results indicate that CD8＋ T cells in the intestinal LP may perform a regulatory role following antigen challenge via the oral route.

• IMMUNE NETWORK
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• 제20권6호
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• pp.51.1-51.17
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• 2020

Respiratory syncytial virus (RSV) causes severe pulmonary disease in infants, young children, and the elderly. Formalin inactivated RSV (FI-RSV) vaccine trials failed due to vaccine enhanced respiratory disease, but the underlying immune mechanisms remain not fully understood. In this study, we have used wild type C57BL/6 and CD4 knockout (CD4KO) mouse models to better understand the roles of the CD4 T cells and cellular mechanisms responsible for enhanced respiratory disease after FI-RSV vaccination and RSV infection. Less eosinophil infiltration and lower pro-inflammatory cytokine production were observed in FI-RSV vaccinated CD4KO mice after RSV infection compared to FI-RSV vaccinated C57BL/6 mice. NK cells and cytokine-producing CD8 T cells were recruited at high levels in the airways of CD4KO mice, correlating with reduced respiratory disease. Depletion studies provided evidence that virus control was primarily mediated by NK cells whereas CD8 T cells contributed to IFN-γ production and less eosinophilic lung inflammation. This study demonstrated the differential roles of effector CD4 and CD8 T cells as well as NK cells, in networking with other inflammatory infiltrates in RSV disease in immune competent and CD4-deficient condition.

• IMMUNE NETWORK
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• 제13권3호
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• pp.86-93
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• 2013

In the present study, we investigated if priming of autoreactive $CD8^+T$ cells would be inhibited by competitive peptides for major histocompatibility complex (MHC) class I binding. We used a mouse model of vitiligo which is induced by immunization of $K^b$-binding tyrosinase-related protein 2 (TRP2)-180 peptide. Competitive peptides for $K^b$ binding inhibited IFN-${\gamma}$production and proliferation of TRP2-180-specific $CD8^+T$ cells upon ex vivo peptide restimulation, while other MHC class I-binding peptides did not. In mice, the capability of inhibition was influenced by T-cell immunogenicity of the competitive peptides. The competitive peptide with a high T-cell immunogenicity efficiently inhibited priming of TRP2-180-specific $CD8^+T$ cells in vivo, whereas the competitive peptide with a low T-cell immunogenicity did not. Taken together, the inhibition of priming of autoreactive $CD8^+T$ cells depends on not only competition of peptides for MHC class I binding but also competitive peptide-specific $CD8^+T$ cells, suggesting that clonal expansion of autoreactive T cells would be affected by expansion of competitive peptide-specific T cells. This result provides new insights into the development of competitive peptides-based therapy for the treatment of autoimmune diseases.