• IMMUNE NETWORK
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• 제3권2호
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• pp.110-117
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• 2003

Background: The usefulness of DNA vaccine at priming step of heterologous prime-boost vaccination led to DNA vaccine closer to practical reality. DNA vaccine priming followed by recombinant viral vector boosting via systemic route induces optimal systemic immunity but no mucosal immunity. Mucosal vaccination of the reversed protocol (recombinant viral vector priming-DNA vaccine boosting), however, can induce both maximal mucosal and systemic immunity. Here, we tried to address the reason why the mucosal protocol of prime-boost vaccination differs from that of systemic vaccination. Methods: To address the importance of primary immunity induced at priming step, mice were primed with different doses of DNA vaccine or coadministration of DNA vaccine plus mucosal adjuvant, and immunity including serum IgG and mucosal IgA was then determined following boosting with recombinant viral vector. Next, to assess influence of humoral pre-existing immunity on boosting $CD8^+$ T cell-mediated immunity, $CD8^+$ T cell-mediated immunity in B cell-deficient (${\mu}K/O$) mice immunized with prime-boost regimens was evaluated by CTL assay and $IFN-{\gamma}$-producing cells. Results: Immunity primed with recombinant viral vector was effectively boosted with DNA vaccine even 60 days later. In particular, animals primed by increasing doses of DNA vaccine or incorporating an adjuvant at priming step and boosted by recombinant viral vector elicited comparable responses to recombinant viral vector primed-DNA vaccine boosted group. Humoral pre-existing immunity was also unlikely to interfere the boosting effect of $CD8^+$ T cell-mediated immunity by recombinant viral vector. Conclusion: This report provides the important point that optimally primed responses should be considered in mucosal immunization of heterologous prime-boost regimens for inducing the effective boosting at both mucosal and systemic sites.

• IMMUNE NETWORK
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• 제22권5호
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• pp.38.1-38.24
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• 2022

Exosomes, which are well-known nanoscale extracellular vesicles, are multifunctional biomaterials derived from endosomes and perform various functions. The exosome is a critical material in cell-cell communication. In addition, it regulates the pathophysiological conditions of the tumor microenvironment in particular. In the tumor microenvironment, exosomes play a controversial role in supporting or killing cancer by conveying biomaterials derived from parent cells. Innate immunity is a crucial component of the host defense mechanism, as it prevents foreign substances, such as viruses and other microbes and tumorigenesis from invading the body. Early in the tumorigenesis process, the innate immunity explicitly recognizes the tumor via Ags and educates the adaptive immunity to eliminate it. Recent studies have revealed that exosomes regulate immunity in the tumor microenvironment. Tumor-derived exosomes regulate immunity against tumor progression and metastasis. Furthermore, tumor-derived exosomes regulate polarization, differentiation, proliferation, and activation of innate immune cells. Exosomes produced from innate immune cells can inhibit or support tumor progression and metastasis via immune cell activation and direct cancer inhibition. In this study, we investigated current knowledge regarding the communication between tumor-derived exosomes and innate immune cell-derived exosomes (from macrophages, dendritic cells, NK cells, and neutrophils) in the tumor microenvironment. In addition, we discussed the potential development of exosomal immunotherapy using native or engineered exosomes against cancer.

• 약학회지
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• 제36권5호
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• pp.412-426
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• 1992

Effects of beta-carotene on the immunobiological responses were studied in ICR mice. ICR male mice were divided into 8 groups (10 mice/group), and beta-carotene at doses of 4, 20 and 100 mg/kg were orally administered to ICR mice once daily for 28 consecutive days. Cyclophosphamide (CY) was injected intraperitoneally (i.p.) to ICR mice with a single dose of 5 mg/kg body weight at 2 days before secondary immunization. Mice were sensitized and challenged with sheep red blood cells (5-RBC). Immune responses were evaluated by humoral immunity, cellular immunity and non-specific immunity. The results of this study were summarized as follows: (1) Beta-carotene significantly increased the weight ratios of liver, spleen and thymus to body weight depending on dose, and significantly increased the increasing rate of body weight and the number of circulating leukocyte. (2) Beta-carotene dose-dependently increased hemagglutination titer, Arthus reaction and hemolytic plaque forming cell related to humoral immunity. (3) Beta-carotene significantly increased delayed-type hypersensitivity reaction and rosette forming cell related to cellular immunity. (4) Beta-carotene dose-dependently increased phagocytic activity, and significantly increased natural killer (NK) cell activity. (5) Beta-carotene dose-dependently inhibited reductions in humoral immunity, cellular immunity, NK cell activity and phagocytic activity by treatment with CY.

• IMMUNE NETWORK
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• 제24권1호
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• pp.9.1-9.21
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• 2024

The cytokine IL-7 plays critical and nonredundant roles in T cell immunity so that the abundance and availability of IL-7 act as key regulatory mechanisms in T cell immunity. Importantly, IL-7 is not produced by T cells themselves but primarily by non-lymphoid lineage stromal cells and epithelial cells that are limited in their numbers. Thus, T cells depend on cell extrinsic IL-7, and the amount of in vivo IL-7 is considered a major factor in maximizing and maintaining the number of T cells in peripheral tissues. Moreover, IL-7 provides metabolic cues and promotes the survival of both naïve and memory T cells. Thus, IL-7 is also essential for the functional fitness of T cells. In this regard, there has been an extensive effort trying to increase the protein abundance of IL-7 in vivo, with the aim to augment T cell immunity and harness T cell functions in anti-tumor responses. Such approaches started under experimental animal models, but they recently culminated into clinical studies, with striking effects in re-establishing T cell immunity in immunocompromised patients, as well as boosting anti-tumor effects. Depending on the design, glycosylation, and the structure of recombinantly engineered IL-7 proteins and their mimetics, recombinant IL-7 molecules have shown dramatic differences in their stability, efficacy, cellular effects, and overall immune functions. The current review is aimed to summarize the past and present efforts in the field that led to clinical trials, and to highlight the therapeutical significance of IL-7 biology as a master regulator of T cell immunity.

• Journal of Digestive Cancer Research
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• 제6권1호
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• pp.11-15
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• 2018

Chemotherapy and surgical resection are the mainstay of cancer treatment. Particularly for chemotherapy, although it is effective method to care, sometimes cure various cancers, there are many different status of cancer not being controlled by chemotherapy such as recurrence and resistance to chemotherapy. In order to overcome those difficulties during cancer therapy, immunotherapy targeting immune cells and immune associated factors to enhance cancer immunity has been highlighted. Innate immunity plays important roles on initial stage of cancer immunity that are detecting, killing cancer cells and initiating adaptive immunity for cancer. So many basic and clinical studies to manage innate immunity for cancer therapy have been going on, and most of them were to stimulate innate immune cells including dendritic cell, macrophage, monocyte, and natural killer cell in various ways. They showed promising results but still there are many things to be resolved before clinical application. Herein, I review the role of innate immune cells and therapeutic trials for colorectal cancer.

• Journal of Chest Surgery
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• 제25권11호
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• pp.1185-1191
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• 1992

Cell mediated immunity is depressed following surgical procedure and the degree of immunosuppression is directly related to the magintude of the procedure, blood transfusion, and length of operation. So we would expect cardiac operations to be highly immunosuppressive, although little is konwn about their immunosuppressive effect. The nearly complete consumption of complement factors and decreased levels of IgM and IgG resulting in an impaired opsonizing capacity. Additionally, peripheral blood mononuclear cell counts including T-and B-lymphocytes and T-cell subsets are reduced. Depression of cell-mediated immunity following open-heart surgery is potentially detrimental because it could increase the susceptability of patients to viral and bacterial infection. We reviewed 20 patients after cardiac operation to search for changes in peripheral blood lymphocyte subsets. Lymphocyte subsets were measured by flow cytometer and the preoperative values of lymphocyte subsets were compared with those from the first, fourth, and seventh days after operation. After cardiac operation, total mumbers of T lymphocyte was severely depressed on the first postoperative day and returned to the preoperative level by the seventh day after operation. CD3, CD4, and CD8 lymphocytes were decreased on the first postoperative day and returned to the preoperative level by the seventh day also. There was four cases of wound infection and these patients had increased CD4 lympocyte and more decreased CD19 lymphocyte compared with the non-infected group. It is concluded from these data that cell-mediated immunity is significantly depressed for at least one week following open-heart surgery and this result was closely related to the postoperative infection.

• Journal of Nutrition and Health
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• 제27권5호
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• pp.483-494
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• 1994

The purpose of this study was to investigate the effect of nutritional status on the cell-mediated and humoral immunity in female college students. The nutritional status of twenty subjects was determined by six-days food records, anthropometric measurements, and biochemical assessments of serum nutrients. Cell-mediated and humoral immunity of the subjects was analyzed by in vivo and in vitro assessments. The results were summerized as follows : First, The average daily energy intake was 1437Kcal(CHO : PRO : FAT = 61:13:26), which corresponds to 71.9% of RDA. Anthropometric measurements showed that 50% of the subjects was under-weight(BMI<20), only 5% was over-weight(25

• IMMUNE NETWORK
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• 제3권3호
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• pp.211-218
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• 2003

Background: Vitamin C is an essential nutrient, taken as a daily supplement by many people. Recently, high-dose vitamin C is considered as a therapeutic regimen in some clinical situations. Until now, few studies have been done with the effects of high-dose vitamin C on the immune response. Methods: In this experiment, the effects of high-dose vitamin C on cell-mediated immune response in immunologically competent mice were evaluated. After intraperitoneal injection of 2.5, 5, or 10 mg/day of vitamin C for 10 days, delayed type hypersensitivity (DTH) was provoked against DNFB in the pinnae as a model for cell-mediated immune response. Severity of DTH reaction was evaluated as the thickness of pinnae, and the vitamin C levels were measured in the serum, liver, kidney, lung, pinnae, and splenocytes. Results: After challenge, the thickness increased at its peak on the $2^{nd}$ day in all groups. On the first day, the pinnae were thicker in the injected groups than in the control. On the contrary, the increment of the pinnae thickness was attenuated and the number of cells infiltrated in the site of DTH decreased proportionately to the amount of vitamin C administered from the second day on. With vitamin C exogenously given, the serum level peaked at 30 min after injection, and returned abruptly to its basal level without accumulation. However, it accumulated in the liver, kidney, and especially in the pinnae inflamed and splenopcytes, proportionately to the amount administered. Conclusion: Based on these results, it is suggested that, in one hand, exogenously administered high-dose vitamin C accumulated in the splenocytes and presumably changed the function of them resulting in the augmented cell-mediated immune response, as was revealed in the first day of DTH reaction. On the other hand, it seems likely that the vitamin C also showed anti-inflammatory effects.

• IMMUNE NETWORK
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• 제16권5호
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• pp.305-310
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• 2016

In this study, we compared two different tumor cell vaccines for their induction of anti-tumor immunity; one was a tumor cell clone expressing a membrane-bound form of IL-12 p35 subunit (mbIL-12 p35 tumor clone), and the other was a tumor clone expressing heterodimeric IL-12 as a single chain (mb-scIL-12 tumor clone). The stimulatory effect of mb-scIL-12 on the proliferation of ConA-activated splenocytes was higher than that of mbIL-12 p35 in vitro. However, the stimulatory effect of mbIL-12 p35 was equivalent to that of recombinant soluble IL-12 (3 ng/ml). Interestingly, both tumor clones (mbIL-12 p35 and mb-scIL-12) showed similar tumorigenicity and induction of systemic anti-tumor immunity in vivo, suggesting that tumor cell expression of the membrane-bound p35 subunit is sufficient to induce anti-tumor immunity in our tumor vaccine model.

• 한국영양학회:학술대회논문집
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• 한국영양학회 1994년도 춘계심포지움 및 발표논문 초록
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• pp.46-46
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• 1994