• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4295-4300
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• 2012

Objective: To investigate the therapeutic potential of human embryonic stem cells (hESCs) as a vaccine to induce an immune response and provide antitumor protection in a rat model. Methods: Cross-reactivity of antigens between hESCs and tumour cells was screened by immunohistochemistry. Fischer 344 rats were divided into 7 groups, with 6 rats in each, immunized with: Group 1, hESC; Group 2, pre-inactivated mitotic NuTu-19; Group 3 PBS; Group 4, hESC; Group 5, pre-inactivated mitotic NuTu-19; Group 6, PBS; Group 7, hESC only. At 1 (Groups 1-3) or 4 weeks (Groups 4-6) after the last vaccination, each rat was challenged intraperitoneally with NuTu-19. Tumor growth and animal survival were closely monitored. Rats immunized with H9 and NuTu-19 were tested by Western blot analysis of rat orbital venous blood for cytokines produced by Th1 and Th2 cells. Results: hESCs presented tumour antigens, markers, and genes related to tumour growth, metastasis, and signal pathway interactions. The vaccine administered to rats in Group 1 led to significant antitumor responses and enhanced tumor rejection in rats with intraperitoneal inoculation of NuTu-19 cells compared to control groups. In contrast, rats in Group 4 did not display any elevation of antitumour responses. Western blot analysis found cross-reactivity among antibodies generated between H9 and NuTu-19. However, the cytokines did not show significant differences, and no side effects were detected. Conclusion: hESC-based vaccination is a promising modality for immunotherapy of ovarian cancer.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.100-108
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• 2011

A method for the rapid detection and quantification of Newcastle disease virus (NDV) produced in an animal cell culture-based production system was developed to enhance the speed of the NDV vaccine manufacturing process. A SYBR Green I-based real-time RT-PCR was designed with a conventional, inexpensive RT-PCR kit targeting the F gene of the NDV LaSota strain. The method developed in this study was validated for specificity, accuracy, precision, linearity, limit of detection (LOD), limit of quantification (LOQ), and robustness. The validation results satisfied the predetermined acceptance criteria. The validated method was used to quantify virus samples produced in an animal cell culture-based production system. The method was able to quantify the NDV samples from mid- or late-production phases, but not effective on samples from the early-production phase. For comparison with other quantifiable methods, immunoblotting, plaque assay, and tissue culture infectious dose 50 ($TCID_{50}$) assay were also performed with the NDV samples. The results demonstrated that the real-time RT-PCR method is suitable for the rapid quantification of virus particles produced in an animal cell-culture-based production system irrespective of viral infectivity.

• Parasites, Hosts and Diseases
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• v.56 no.4
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• pp.325-334
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• 2018

Toxoplasma gondii is an apicomplexan zoonotic protozoan parasite that infects most species of warm-blooded animals, including humans. The heavy incidence and severe or lethal damage caused by T. gondii infection clearly indicate a need for the development of an effective vaccine. T. gondii GRA8 is a member of the dense granules protein family and is used as a marker of acute infection. In the present study, we evaluated the protective immunity induced by DNA vaccination based on a recombinant eukaryotic plasmid, pDsRed2-GRA8, against acute toxoplasmosis in mice. BALB/c mice were intramuscularly immunized with the pDsRed2-GRA8 plasmid and then challenged by infection with the highly virulent GFP-RH strain of T. gondii. The specific immune responses and protective efficacy against T. gondii of this vaccine were analyzed by measuring cytokine and serum antibody titers, splenocyte proliferation assays, and the survival times of mice after challenge. Our results showed that mice immunized with pDsRed2-GRA8 demonstrated specific humoral and cellular responses, induced higher IgG antibody titers with predominant IgG2a production; increased levels of IL-10, IL-12 (p70), $IFN-{\gamma}$, $TNF-{\alpha}$, and splenocyte proliferation; and prolonged survival times compared to those of control mice. The present study showed that DNA immunization with pDsRed2-GRA8 induced humoral and cellular immune responses, and all immunized mice showed greater Th1-type immune responses and longer survival times than those of control mice. These results indicated that T. gondii GRA8 DNA immunization induces a partial protective effect against acute toxoplasmosis.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5973-5981
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• 2013

At present, the most common cause of cancer-related death in women is breast cancer. In a large proportion of breast cancers, there is the overexpression of human epidermal growth factor receptor 2 (HER2). This receptor is a 185 KDa growth factor glycoprotein, also known as the first tumor-associated antigen for different types of breast cancers. Moreover, HER2 is an appropriate cell-surface specific antigen for passive immunotherapy, which relies on the repeated application of monoclonal antibodies that are transferred to the patient. However, vaccination is preferable because it would stimulate a patient's own immune system to actively respond to a disease. In the current study, several bioinformatics tools were used for designing synthetic peptide vaccines. PEPOP was used to predict peptides from HER2 ECD subdomain III in the form of discontinuous-continuous B-cell epitopes. Then, T-cell epitope prediction web servers MHCPred, SYFPEITHI, HLA peptide motif search, Propred, and SVMHC were used to identify class-I and II MHC peptides. In this way, PEPOP selected 12 discontinuous peptides from the 3D structure of the HER2 ECD subdomain III. Furthermore, T-cell epitope prediction analyses identified four peptides containing the segments 77 (384-391) and 99 (495-503) for both B and T-cell epitopes. This work is the only study to our knowledge focusing on design of in silico potential novel cancer peptide vaccines of the HER2 ECD subdomain III that contain epitopes for both B and T-cells. These findings based on bioinformatics analyses may be used in vaccine design and cancer therapy; saving time and minimizing the number of tests needed to select the best possible epitopes.

• Journal of Microbiology and Biotechnology
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• v.32 no.5
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• pp.621-629
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• 2022

Bacterial outer membrane vesicles (OMVs) typically contain multiple immunogenic molecules that include antigenic proteins, making them good candidates for vaccine development. In animal models, vaccination with OMVs has been shown to confer protective immune responses against many bacterial diseases. It is possible to genetically introduce heterologous protein antigens to the bacterial host that can then be produced and relocated to reside within the OMVs by means of the host secretion mechanisms. Accordingly, in this study we sought to develop a novel platform for recombinant OMV (rOMV) production in the widely used bacterial expression host species, Escherichia coli. Three different lipoprotein signal peptides including their Lol signals and tether sequences-from Neisseria meningitidis fHbp, Leptospira interrogans LipL32, and Campylobactor jejuni JlpA-were combined upstream to the GFPmut2 model protein, resulting in three recombinant plasmids. Pilot expression studies showed that the fusion between fHbp and GFPmut2 was the only promising construct; therefore, we used this construct for large-scale expression. After inducing recombinant protein expression, the nanovesicles were harvested from cell-free culture media by ultrafiltration and ultracentrifugation. Transmission electron microscopy demonstrated that the obtained rOMVs were closed, circular single-membrane particles, 20-200 nm in size. Western blotting confirmed the presence of GFPmut2 in the isolated vesicles. Collectively, although this is a non-optimized, proof-of-concept study, it demonstrates the feasibility of this platform in directing target proteins into the vesicles for OMV-based vaccine development.

• KSBB Journal
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• v.19 no.6 s.89
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• pp.415-420
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• 2004

All around the world, the rate of attack of cancer diseases has been going up and the number of cancer patients has been increasing every year. Cancer can be divided into malignant tumor and benign tumor according to its growth appearance. Many studies and experiments have been conducted and the various treatment are being created to find the way to care malignant. Dendritic cells (DCs), which is an agent of cancer treatments by using an immune reaction in our body, plays an important role to present by a tumor antigen to cytotoxic T-cell and help them to attack the tumor cell directly. However there are some defects of this therapy. Soluble human leukocyte antigen-immunoglobulin fusion protein (HLA-Ig) based artificial antigen presenting cell (aAPC) as the antigen presenting cell (APC) which is complement and overcome some of the limitations of dendritic cell-based vaccines and ex vivo expansion of human T cells is new method for cancer therapy. In this article, we are reviewing the role of DCs and the treatment with it, and searching for the possibility of the new development of immunotherapy for cancer.

• KSBB Journal
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• v.19 no.5
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• pp.341-347
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• 2004

Several gene delivery therapies are being developed for treatment of serum protein deficiency. EPO is one of the most promising therapeutic agent for this treatment which is currently being investigated in depth. This study has the ultimate purpose of improving the gene delivery system for an increase of red blood cell production. A plasmid DNA was constructed smaller than other plasmids for an increase in penetration into animal cells, and two genes were cloned into each vector as a co-delivery system to express erythropoietin, and interluekin-3 or thrombopoietin, which can act on erythroid cell, thus activating hematopoiesis synergically. This co-delivery system has an advantage of decreasing the labour required for industrial production of DNA vaccine. A new plasmid vector, pVAC, in size 2.9 kb, was constructed with the essential parts from PUC 19 and pSectagB, which is much smaller than other plasmid vector and is the size of 2.9 kb. Co-delivery system was constituted by cloning human erythropoietin with each of human interluekin-3 gene or human thrombopoietin gene into both pVAC and pSectagB. As a result, the transfection efficiency of pVAC was higer than that of pSectagB in vitro, and hematocrit level of the mice injected with pVAC is higher than that of other mice. And co-delivery system, made of several plasmid DNAs, was expressed in vitro.

• Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.98-103
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• 2009

The potential utility of the rockbream (Oplegnathus fasciatus) $\beta$-actin 5'-upstream sequence as a regulatory element for DNA vaccination was evaluated based on in vitro and in vivo heterologous expression assays. In the in vitro transfection experiment, the efficacy of the rockbream $\beta$-actin promoter to drive the expression of a downstream lacZ gene was significantly higher (more than fourfold) than that of the human cytomegalovirus (hCMV) promoter in two fish cell lines (grunt Haemulon plumierii fin and bluegill Lepomis macrochirus fry cell lines). In contrast, the functional activity of the rockbream $\beta$-actin promoter was hardly detectable in a mammalian mouse embryonic fibroblast cell line. Rockbream skeletal muscles injected in vivo with a GFP reporter construct driven by the $\beta$-actin promoter displayed the significantly higher expression of a GFP protein (more than threefold) than did those injected with hCMV promoter driven construct. Data from this study suggest that the homologous rockbream $\beta$-actin promoter could be used as a potential regulator for DNA vaccination in this species.

• Osong Public Health and Research Perspectives
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• v.8 no.6
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• pp.389-396
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• 2017

Objectives: To circumvent the limitations of the current golden standard method, colony-forming unit (CFU) assay, for viability of Bacille Calmette-$Gu{\acute{e}}rin$ (BCG) vaccines, we developed a new method to rapidly and accurately determine the potency of BCG vaccines. Methods: Based on flow cytometry (FACS) and fluorescein diacetate (FDA) as the most appropriate fluorescent staining reagent, 17 lots of BCG vaccines for percutaneous administration and 5 lots of BCG vaccines for intradermal administration were analyzed in this study. The percentage of viable cells measured by flow cytometry along with the total number of organisms in BCG vaccines, as determined on a cell counter, was used to quantify the number of viable cells. Results: Pearson correlation coefficients of FACS and CFU assays for percutaneous and intradermal BCG vaccines were 0.6962 and 0.7428, respectively, indicating a high correlation. The coefficient of variation value of the FACS assay was less than 7%, which was 11 times lower than that of the CFU assay. Conclusion: This study contributes to the evaluation of new potency test method for FACS-based determination of viable cells in BCG vaccines. Accordingly, quality control of BCG vaccines can be significantly improved.

• IMMUNE NETWORK
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• v.5 no.3
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• pp.163-171
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• 2005

Background: To perform the successful dendritic cell-based cancer immunotherapy one of the main issues to be solved is the source of antigen for DC pulsing. Limitations occur by using auto-tumor lysate due to the difficulties obtaining enough tumor tissue(s) quantitatively as well as qualitatively. In this study the possibility of allogeneic tumor cell lysate as a DC pulsing antigen has been tested in mouse melanoma pulmonary me tastasis model. Methods: B16F10 melanoma cells $(1{\timeS}10^5/mouse)$ were inoculated intra venously into the C57BL/6 mouse. Therapeutic DCs were cultured from the bone marrow myeloid lineage cells with GM-CSF and IL-4 (1,000 U/ml each) for 7 days and pulsed with lysate of either autologous B16F10 (B-DC), allogeneic K1735 (C3H/He origin; K-DC) or CloneM3 (DBA2 origin; C-DC) melanoma cells for 18 hrs. Pulsed-DCs $(1{\times}10^6/mouse)_{[CGP1]}$ were injected i.p. twice with one week interval starting from the day 1 after tumor cell inoculation. Results: Without observable toxicity, allogeneic tumor cell lysate pulsed-DC induced the significantly better anti-tumor response (tumor scale: $2.7{\pm}0.3,\;0.7{\pm}0.3\;and\;0.3{\pm}0.2$ for saline, B-DC and C-DC treated group, respectively). Along with increased tumor specific lymphocyte proliferations, induction of IFN-${\gamma}$ secretion against both auto- and allo-tumor cell lysates was observed from the DC treated mice. (w/B16F10-lysate: $44.97{\pm}10.31,\;1787.94{\pm}131.18,\;1257.15{\pm}48.27$, w/CloneM3 lysate: 0, $1591.13{\pm}1.83,\;1460.47{\pm}86.05pg/ml$ for saline, B-DC and C-DC treated group, respectively) Natural killer cell activity was also increased in the mice treated with tumor cell lysate pulsed-DC ($8.9{\pm}_{[CGP2]}0.1,\;11.6{\pm}0.8\;and\;12.6{\pm}0.7%$ specific NK activity for saline, B-DC and C-DC treated group, respectively). Conclusion: Conclusively, promising data were obtained that allogeneic-tumor cell lysate can be used as a tumor antigen for DC-based cancer immunotherapy.