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Polysorbitol Transporter as Novel Vaccine Carrier and Adjuvant Elicits Prolonged Antibody Response
Full text link학위논문 (박사)-- 서울대학교 대학원 : 농생명공학부, 2015. 2. 윤철희.Effective delivery together with the action of adjuvant is essential for enhanced, long lasting and protective efficacy of the vaccine. Thus, the interest to develop such strategy (i.e., delivery tools and adjuvants) for the vaccination is getting a great attention in the public as well as private sectors. In the present study, I evaluated polysorbitol transporter (PST), a polysaccharide-based polymer as a delivery system and an adjuvant in terms of the induction of long-lasting antigen-specific antibody response.
In the first approach, I demonstrated PST for its application as both a potential adjuvant system and polymeric delivery tool for respiratory syncytial virus (RSV) glycoprotein antigen. RSV is one of the most common causes of viral deaths in infants worldwide, yet there are no effective vaccines available. PST is prepared from sorbitol diacrylate and low molecular weight polyethylenimine (PEI). Unlike PEI and the pre-existing experimental mucosal adjuvant, cholera toxin (CT), PST showed no toxicity in vitro and in vivo. The osmotically active PST formed nano-sized complexes with RGp by simple mixing, retained the antigenic stability and exhibited negative surface charges made them highly effective for the activation of phagocytic cells and enhancement of phagocytosis-mediated uptake. This resulted in an improved cytokine expression and the significant augmentation of RGp-specific antibody production with long-term persistency over 200 days. Interestingly, PST/RGp enhanced phagocytic cell-mediated uptake owing to the osmotic property of PST and negative zeta potential, suggesting that PST could specifically stimulate phagocytic cells for long-lived antigen-specific immune response, where the polysaccharide properties of PST might also play a role in the induction of prolonged memory response.
In the second approach, I have investigated a mechanism on PST-mediated long-lasting antibody response using a model protein, ovalbumin (OVA). The result showed that PST/OVA targeted mainly APCs and mostly the B cells in mediastinal lymph node (MdLN) after intranasal delivery. As secondary lymphoid organ, this draining lymph node is providing a site for iNKT cell activation at germinal center in response to higher number of CD1d expressed cells specially macrophage, dendritic cells, B cells and neutrophils. Interestingly, a significant number of CD1d+ cells were also found OVA positive i.e. antigen specific.
In the third approach, the existence of OVA-specific antibody secreting cells were investigated thoroughly in bone marrow, lung, spleen, MdLN and other lymph nodes Interestingly, PST/OVA system showed persisted antibody response for a long period of time (over 90 days and up to 500 days after the last immunization) The results showed that PST continuously maintained OVA-specific plasma cells in MdLN as well as in bone marrow from days 7 to 90 after the last immunization. OVA-specific germinal center B cells were also appeared in the MdLN from soon after the last immunization throughout the experimental period. On the other hand, the germinal center B cells showed a significantly increased number and characteristic of antigen specific plasma cells at days 60 and 90 after the last immunization in MdLN of PST/OVA-immunized mice upon OVA restimulation ex vivo. Furthermore, higher OVA-specific IgG was found in the supernatant in which they were cultured. Interestingly, in MdLN, potential OVA-specific B cells were maintained up to day 90 from the last immunization. It is worthy to mention that, PST exhibited long-term antigen-specific antibody response without showing any polymer-specific antibody response, which is particularly one of the necessary properties for vaccine delivery to improve the efficacy of antigen-specific immunity.
In conclusion, all of the results indicate that PST is a promising adjuvant and functional delivery material for vaccine, devoid of side effects, able to stimulate innate immune system and most importantly induces the long-lasting antibody response with some unique mechanisms, especially with CD1d-mediated iNKT cell activation.Abstract i
Contents iv
List of Figures vii
List of Tables xiv
Chapter I: General Introduction 1
1-1. Overview of vaccine developments 2
1-2. Barriers to develop effective vaccine 5
1-3. Vaccine delivery systems and adjuvants 7
1-4. Challenges of available vaccine carriers
and adjuvants 10
1-5. Stimulation of innate immune system and persistence of adaptive immunity: importance, challenges and mechanism 14
1-6. Design of polysorbitol transporter as a novel delivery tool and adjuvant to stimulate APC and persist immunity 18
1-7. Objectives of the studies 22
1-8. References 25
Chapter II: Induction of Long-Term Immunity Against Respiratory Syncytial Virus Glycoprotein by an Osmotic Polymeric Nanocarrier 34
2-1. Introduction 35
2-2. Materials and Methods 37
2-3. Results and Discussion 45
2-4. Summary and Future Prospective 66
2-5. References 67
Chapter III: PST Causes CD1d Expression in Phagocytes and B Cells to induce iNKT Cell Activation 72
3-1. Introduction 73
3-2. Materials and Methods 75
3-3. Results and Discussion 79
3-4. Summary and Future Prospective 93
3-5. References 95
Chapter IV: PST Facilitates the Maintenance of Germinal Centre B Cells for Long-Lasting Antigen-Specific Antibody Response in Draining Lymph Node 99
4-1. Introduction 100
4-2. Materials and Methods 101
4-3. Results and Discussion 106
4-4. Summary and Future Prospective 119
4-5. References 121
Chapter V: Concluding Remarks 124
Acknowledgements 128
List of Publications 134
Awards/Honors 135Docto
인공지능에 의한 돼지 소장상피세포의 장벽기능 식별
No full text학위논문(석사)--서울대학교 대학원 :농업생명과학대학 농생명공학부,2020. 2. Cheol-Heui Yun.Given the importance of monitoring intestinal permeability and the significant healthcare cost associated with the gut barrier disruption, automatic detection of barrier disruption pattern in porcine intestinal epithelial cells (IPEC-J2) using automatically computer-aided detection models based on a deep convolutional neural network for early detection and interpretation in measuring intestinal permeability is an area of active research and adequate experimental models are required to further understand the grade of localization and disruption of IPEC-J2 tight junction proteins.
In the present study, a deep learning-based ensemble model to build a classifier to automatically analyze and extract features from input images in order to accurately assess the grade of localization and disruption of tight junction proteins (TJ) in IPEC-J2 have been proposed. Different data augmentation techniques including horizontal and vertical flips, rotating, zooming, contrast adjustment and brightness enhancement with different parameters are employed to increase the dataset size and tackle the over-fitting problem. At first, the experiments began with evaluating the performance of 8 state-of-the-art deep CNN architectures namely, VGG-Net, InceptionV3, MobileNet, DenseNet, Xception, NAS-Net, InceptionResNetV2 and ResNet models on IPEC-J2 cell image classification. Transfer learning is a common strategy in training deep CNN models. Using this strategy, the weights that are already learned on a cross-domain dataset to initialize weights of deep CNN models can be transferred in this research. The final results showed that the deep CNN ensemble of InceptionV3 and DenseNet201 achieved the best result with an accurate detection rate of 99.22% than the individual InceptionV3 architecture (95.03%) and the individual DenseNet201 architecture (91.11%). The second-best ensemble architecture was the ensemble of InceptionV3 and MobileNet with an accuracy of 97.78% than the individual InceptionV3 architecture (95.03%) and the individual MobileNet architecture (95.82%.)
Collectively, employing CNN models could be considered as an automatic visual inspection system for the recognition, grading of expression, localization and disruption of tight junction proteins in epithelial cells with less misdiagnosis (false positive or false negative) and error rate, and also reduce the heavy workload of manual diagnosis.Ι. Review of Literature 1
1. Convolutional neural network 1
1.1 Characterization and design of generalized convolutional neural network 1
1.1.1 Convolution layer 1
1.1.2 Rectified linear unit function 2
1.1.3 Pooling layer 3
1.1.4 Fully connected layer 3
1.2 Feature extraction using transfer learning 5
1.2.1 InceptionV3: 5
1.2.2 Xception: 5
1.2.3 MobileNet: 6
1.2.4 NAS-Net: 6
1.2.5 ResNet50: 6
1.2.6 DenseNet: 7
1.2.7 VGG-Net: 7
1.2.8 InceptionResNetV2: 7
2. Intestinal barrier and pathways of permeability 8
3. Tight junction proteins 11
3.1 Characterization of intestinal tight junction proteins 11
3.2 Zonula occluden family 11
3.3 Occludin family 12
3.4 Claudin family 12
4. Experimental evaluation of intestinal barrier function 13
4.1 Limitation for the evaluation of intestinal permeability 13
4.2 Future direction for the evaluation of the intestinal permeability 17
5. The beneficial effect of deep convolutional neural network 18
П. Introduction 19
Ш. Materials and methods 21
1. Methodology 21
2. Motivation and Contribution 22
2.1 The contribution of the proposed ensemble model 22
2.2 Two-path ensemble architecture for IPEC-J2 cell image classification 23
ΙV. Experiment 26
1. Dataset description 26
2. Data pre-processing 34
2.1 Resizing: 34
2.2 Z-score image normalization: 34
2.3 Image normalization: 34
3. Data augmentation 34
4. Metrics for performance evaluation 36
5. Experimental Setup 36
V. Results 37
1. Deep features extraction based on transfer learning 37
2. Deep feature extraction based on deep learning-based ensemble models 39
VΙ. Discussion 43
VΠ. Literature cited 45
VШ. Acknowledgement 58
ΙХ. Appendix 60Maste
Expect the unexpected: memorable experiences at the 2018 Council of Science Editors annual meeting
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Consultation questions on publication ethics from 2016 to 2020 addressed by the Committee on Publication Ethics of the Korean Council of Science Editors
Full text linkWith the goal of improving the publishing ecosystem and promoting transparency in journal publishing, we describe some recent cases in scientific publishing in Korea. The current article summarizes ethical inquiries from domestic journals and publishers, most of whom are members of the Korean Council of Science Editors. We selected 15 representative questions asked during the last 4 years. Those inquiries were classified into hot topics such as plagiarism, duplicate publications, multiple submission, and others (informed consent, copyright, compliance with journal regulations, authors’ responsibilities, and voluntary retraction requests). When plagiarism is suspected, editors and reviewers should assess the situation following the relevant rules and procedures, and if necessary, the manuscript should be rejected. Cases of duplicate publication should be clearly stated in both papers based on the explicit agreement of the editor-in-chief of both journals. As a general rule, the entire content of an article should be published in one issue, but if the article is too long, it may need to be published in two issues. Permission from both journals is required. The abstract and references should be separated accordingly. In cases of copyright conflict, voluntary withdrawal of a paper, or non-compliance with publishing regulations, the manuscript must be withdrawn according to specific procedures (referring to the COPE flow chart). All correspondence regarding a manuscript should be with the corresponding author, who communicates directly with the journal. We hope that these recommendations will help readers in the field of scientific publishing to address issues related to publication ethics
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Current status and demand for educational activities on publication ethics by academic organizations in Korea: a descriptive study
Full text linkPurpose This study aimed to examine the following overarching issues: the current status of research and publication ethics training conducted in Korean academic organizations and what needs to be done to reinforce research and publication ethics training. Methods A survey with 12 items was examined in a pilot survey, followed by a main survey that was distributed to 2,487 academic organizations. A second survey, which contained six additional questions, was dispatched to the same subjects. The results of each survey were analyzed by descriptive statistical analysis, content analysis, and comparative analysis. Results More than half of the academic organizations provided research and publication ethics training programs, with humanities and social sciences organizations giving more training than the others (χ2=11.190, df=2, P=0.004). The results showed that research and publication ethics training was held mostly once and less than an hour per year, mainly in a lecture format. No significant difference was found in the training content among academic fields. The academic organizations preferred case-based discussion training methods and wanted expert instructors who could give tailored training with examples. Conclusion A systematic training program that can develop ethics instructors tailored to specific academic fields and financial support from academic organizations can help scholarly editors resolve the apparent gap between the real and the ideal in ethics training, and ultimately to achieve the competency needed to train their own experts
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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