• IMMUNE NETWORK
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• v.5 no.3
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• pp.172-178
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• 2005

Background: Carcinoembryonic antigen (CEA) is well-known soluble tumor marker frequently detectable in peripheral blood of carcinoma patients and considered as good target for antigen-specific immunotherapy. However, it is known that the induction of immune response to CEA is very difficult because CEA is a self-antigen expressed in fetal cells and weakly expressed in normal colorectal epithelial cells. To enhance anti-tumor immunity specific for CEA, recombinant CEA protein was modified using listeriolysin O (LLO) for endosomal lysis and trans activator of transcription (Tat) domain for transducing extracellular proteins into cytoplasm. Methods: After immunization using dendritic cells pulsed with Tat-CEA, both Tat-CEA and LLO, and both Tat-CEA and Tat-LLO, antibody titer to CEA and LLO, cytotoxic T lymphocyte activity and the frequency of IFN-${\gamma}$ producing T lymphocytes were measured. Results: Immunization using DC pulsed with both Tat-CEA and Tat-LLO protein showed the increasement of production of CEA-specific antibody in serum, cytotoxic T lymphocyte activity, the frequency of IFN-${\gamma}$ secreting T cells, compared with DC pulsed with both Tat-CEA and LLO. Furthermore the ratio of CD8+T cell to $CD4^+$ cell among CEA-specific T cells was increased in group pulsed with both Tat-CEA and Tat-LLO. Conclusion: These results suggested that DC vaccine using Tat-LLO could be used for the development of effective immunotherapy for the treatment of tumor.

• IMMUNE NETWORK
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• v.5 no.3
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• pp.157-162
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• 2005

Background: 1-8D gene is a member of human 1-8 interferon inducible gene family and was shown to be overexpressed in fresh colon cancer tissues. Three peptides 1-6, 3-5 and 3-7 derived from human 1-8D gene were shown to have immunogenicity against colon cancer. Methods: To study tumor immunotherapy, of three peptides we established an active immunization model using HHD mice. $D^{b-/-}{\times}{\beta}2$ microglobulin $({\beta}2m)$ null mice transgenic for a chimeric HLA-$A2.1/D^{b-}\;{\beta}2m$ single chain (HHD mice) were challenged with B16/HHD/1-8D tumor cells and were immunized with irradiated peptide-loaded RMA- S/HHD/B7.1 transfectants. In therapy model tumor growth was retarded in HHD mice that were injected with 3-5 peptide-loaded RMA-S/HHD/B7.1. In survival test vaccination with 1-8D-derived peptide protects HHD mice from tumor progression after tumor challenge. Results: These studies show that peptide 3-5 derived from 1-8D gene can be the most effective candidate for the vaccine of immunotherapy against colon cancer and highlight 1-8D gene as putative colon carcinoma associated antigens. Conclusion: We demonstrated that RMA-S/HHD/ B7.1 loaded with 1-8D peptides, especially 3-5, immunization generates potent antitumor immunity against tumor cells in HHD mice and designed active immunization as proper immunotherapeutic protocols.

• IMMUNE NETWORK
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• v.12 no.6
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• pp.247-252
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• 2012

Pancreatic cancer is the fourth commonest cause of cancer-related deaths in the world. However, no adequate therapy for pancreatic cancer has yet been found. In this study, the antitumor activity of cytokine-induced killer (CIK) cells against the human pancreatic cancer was evaluated in vitro and in vivo. Human peripheral blood mononuclear cells were cultured with IL-2-containing medium in anti-CD3 for 14 days. The resulting populations of CIK cells comprised 94% $CD3^+$, 4% $CD3^-CD56^+$, 41% $CD3^+CD56^+$, 11% $CD4^+$, and 73% $CD8^+$. This heterogeneous cell population was called cytokine-induced killer (CIK) cells. At an effector-target cell ratio of 100 : 1, CIK cells destroyed 51% of AsPC-1 human pancreatic cancer cells, as measured by the $^{51}Cr$-release assay. In addition, CIK cells at doses of 3 and 10 million cells per mouse inhibited 42% and 70% of AsPC-1 tumor growth in nude mouse xenograft assays, respectively. This study suggests that CIK cells may be used as an adoptive immunotherapy for pancreatic cancer patients.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3843-3847
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• 2015

Background: Cervical cancer is the second most common cause of cancer related death of women. Persistent HPV infection, especially with high-risk types such as HPV16 and HPV18, has been identified to be the primary cause of cervical cancer. E6 and E7 are the major oncoproteins of high-risk HPVs, which are expressed exclusively in HPV infected tissues, and thereby represent ideal therapeutic targets for immunotherapy of cervical cancer. Materials and Methods: In this work, we used recombinant adenovirus expressing coden-optimized HPV16 E6 and E7 fusion protein (Ad-ofE6E7) to prime dendritic cells (DC-ofE6E7), to investigate the ability of primed DC vaccine in eliciting antitumor immunity in vitro and vivo. Results: Our results indicated that DC-ofE6E7 vaccine co-culturing with splenocytes could strongly induce a tumor-specific cytotoxic T lymphocyte (CTL) response and kill the TC-1 cells effectively in vitro. Moreover, DC-ofE6E7 vaccine induced protective immunity against the challenge of TC-1 cancer cells in vivo. Conclusions: The results suggested that the HPV16 ofE6E7 primed DC vaccine has potential application for cervical cancer immunotherapy.

• Journal of Ginseng Research
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• v.35 no.4
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• pp.462-470
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• 2011

Myeloid-derived suppressor cells (MDSCs) actively suppress immune cells and have been considered as an impediment to successful cancer immunotherapy. Many approaches have been made to overcome such immunosuppressive factors and to exert effective anti-tumor effects, but the possibility of using medicinal plants for this purpose has been overlooked. Korean red ginseng (KRG) is widely known to possess a variety of pharmacological properties, including immunoboosting and anti-tumor activities. However, little has been done to assess the anti-tumor activity of KRG on MDSCs. Therefore, we examined the effects of KRG on MDSCs in tumor-bearing mice and evaluated immunostimulatory and anti-tumor activities of KRG through MDSC modulation. The data show that intraperitoneal administration of KRG compromises MDSC function and induces T cell proliferation and the secretion of IL-2 and IFN-${\gamma}$, while it does not exhibit direct cytotoxicity on tumor cells and reduced MDSC accumulation. MDSCs isolated from KRG-treated mice also express significantly lower levels of inducible nitric oxide synthase and IL-10 accompanied by a decrease in nitric oxide production compared with control. Taken together, the present study demonstrates that KRG enhances T cell function by inhibiting the immunosuppressive activity of MDSCs and suggests that although KRG alone does not exhibit direct anti-tumor effects, the use of KRG together with conventional chemo- or immunotherapy may provide better outcomes to cancer patients through MDSC modulation.

• BMB Reports
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• v.45 no.7
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• pp.408-413
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• 2012

Almost all melanoma cells express at least one member of the MAGE-A antigen family, making the cytotoxic T cells (CTLs) epitopes with cross-immunizing potential in this family attractive candidates for the broad spectrum of anti-melanoma immunotherapy. In this study, four highly homologous peptides (P264: FLWGPRALA, P264I9: FLWGPRALI, P264V9: FLWGPRALV, and P264H8: FLWGPRAHA) from the MAGE-A antigens were selected by homologous alignment. All four peptides showed high binding affinity and stability to HLA-A$^*02:01$ molecules, and could prime CTL immune responses in human PBMCs and in HLA-A$^*02:01/K^b$ transgenic mice. CTLs elicited by the four epitope peptides could cross-lyse tumor cells expressing the mutual target antigens, except MAGE-A11 which was not tested. However, CTLs induced by P264V9 and P264I9 showed the strongest target cell lysis capabilities, suggesting both peptides may represent the common CTL epitopes shared by the eight MAGE-A antigens, which could induce more potent and broad-spectrum antitumor responses in immunotherapy.

• Molecules and Cells
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• v.42 no.12
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• pp.869-883
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• 2019

Interleukin (IL)-15 is an essential immune-modulator with high potential for use in cancer treatment. Natural IL-15 has a low biological potency because of its short half-life and difficulties in mass-production. IL-15Rα, a member of the IL-15 receptor complex, is famous for its high affinity to IL-15 and its ability to lengthen the half-life of IL-15. We have double-transfected IL-15 and its truncated receptor IL-15Rα into CT26 colon cancer cells to target them for intracellular assembly. The secreted IL-15:IL-15Rα complexes were confirmed in ELISA and Co-IP experiments. IL-15:IL-15Rα secreting clones showed a higher anti-tumor effect than IL-15 secreting clones. Furthermore, we also evaluated the vaccine and therapeutic efficacy of the whole cancer-cell vaccine using mitomycin C (MMC)-treated IL-15:IL-15Rα secreting CT26 clones. Three sets of experiments were evaluated; (1) therapeutics, (2) vaccination, and (3) long-term protection. Wild-type CT26-bearing mice treated with a single dose of MMC-inactivated secreted IL-15:IL-15Rα clones prolonged survival compared to the control group. Survival of MMC-inactivated IL-15:IL-15Rα clone-vaccinated mice (without any further adjuvant) exceeded up to 100%. This protection effect even lasted for at least three months after the immunization. Secreted IL-15:IL-15Rα clones challenging trigger anti-tumor response via CD4⁺ T, CD8⁺ T, and natural killer (NK) cell-dependent cytotoxicity. Our result suggested that cell-based vaccine secreting IL-15:IL-15Rα, may offer the new tools for immunotherapy to treat cancer.

• YAKHAK HOEJI
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• v.47 no.3
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• pp.159-166
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• 2003

In order to study the clinical usefulness of crude polysaccharides fractionated from Eleutherococcus senticosus, EN-3, in eliminating tumors, we have investigated the effect of combination therapy on the murine tumor metastasis and growth models. In experimental metastasis of colon26-M3.1 cells, prophylactic intravenous (i.v.) administration of EN-3 (0.5, 5, and 50 $\mu\textrm{g}$/mouse) inhibited tumor metastasis compared with tumor control group in 33.6, 66.8, and 81.8％ respectively. The administration of EN-3 (50 $\mu\textrm{g}$/mouse) also exhibited a 66.1％ therapeutic effect on lung tumor metastasis. Although EN-3 induced no toxic effect on both tumor cell and normal splenocyte in the concentration below 100 $\mu\textrm{g}$/mι in in vitro, it induced significant proliferating activity on normal splenocyte in the concentration-dependent manner. In an analysis of NK-cell activity, i.v. administration of EN-3 (4∼100 $\mu\textrm{g}$/mouse) significantly augmented NK cytotoxicity to YAC-1 tumor cells. The combination treatments of cisplatin (10 $\mu\textrm{g}$) and EN-3 (5 $\mu\textrm{g}$) induced synergistic effect on the inhibition of tumor metastasis in experimental tumor metastasis model produced by colon26-M3.1 cells. In addition, the combination treatments also exhibited prolongation of lifespan in S∼180 tumor bearing mouse for over the 60 days. Even though cisplatin (2.5 $\mu\textrm{g}$/mι) exhibited cytotoxicity to tumor cells and inhibited tumor growth over 95％ in in vitro, combination treatment with EN-3 (20 $\mu\textrm{g}$/mι) was induced splenocyte proliferation and produced cytokines, such as TNF-$\alpha$, IL-1 and IL-12, from the macrophages. These results suggested that EN-3 stimulate immune system non-specifically and apply to the biological response modifiers (BRM) in chemo-immunotherapy for tumor prevention.

• 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.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.687-690
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• 2011

Purpose: Pemphigus vulgaris, a rare autoimmune blistering disease of the skin and mucous membranes remains a challenging disease to treat. Management is focused on immunotherapy against autoimmune antibodies that target keratinocyte cell adhesion molecules, and antibiotics preventing secondary infections. There is no established dressing protocol and skin is usually manipulated the least amount possible in order to minimize irritation. The authors suggest that early initiation of aggressive bathing and debridement of skin lesions, with nutritional support, is essential in accelerating resolution. Methods: A 40 year-old male previously diagnosed with pemphigus vulgaris was admitted due to exacerbation of mucocutaneous lesions involving the epidermis and mucosa of the whole body. Steroids, immunosuppressants, intravenous immunoglobulin and antibiotics were administrated, but infection and de-epithelialization progressed, while his general condition deteriorated with a weight loss of over 20 kilograms. The plastic surgery department intervened with daily bathing, debridement of unhealthy debris and non-traumatizing coverage of growing epithelium. Total parenteral nutrition and mobilization with rehabilitation therapy was initiated as early as possible. Results: After bathing, healthy epithelium gradually covered the patient's entire body, while his general condition improved with a corresponding weight gain of 14 kgs. Conclusion: Treatment of pemphigus vulgaris focuses on immunotherapy and infection control. However, an equal amount of attention should be laid on early intervention with daily dressings including bathing and irrigation, nutritional support, and exercise as this accelerates resolution of existing infections, promotes healthy epithelialization and leads to faster recovery.