Thesis (Ph.D.)--University of Alberta, 2009. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor in Philosophy in Experimental Surgery, Department of Surgery. Title from pdf file main screen (viewed on October 13, 2009). Includes bibliographical references.

Liver macrophages (LMs) play a central role in acute and chronic liver pathologies. Investigation of these processes in humans as well as the development of diagnostic tools and new therapeutic strategies require in vitro models that closely resemble the in vivo situation. In our study, we sought to gain further insight into the role of LMs in different liver pathologies and into their characteristics after isolation from liver tissue. For this purpose, LMs were characterized in human liver tissue sections using immunohistochemistry and bioinformatic image analysis. Isolated cells were characterized in suspension using FACS analyses and in culture using immunofluorescence staining and laser scanning microscopy as well as functional assays. The majority of our investigated liver tissues were characterized by anti-inflammatory LMs which showed a homogeneous distribution and increased cell numbers in correlation with chronic liver injuries. In contrast, pro-inflammatory LMs appeared as temporary and locally restricted reactions. Detailed characterization of isolated macrophages revealed a complex disease dependent pattern of LMs consisting of pro- and anti-inflammatory macrophages of different origins, regulatory macrophages and monocytes. Our study showed that in most cases the macrophage pattern can be transferred in adherent cultures. The observed exceptions were restricted to LMs with pro-inflammatory characteristics.

The wide scale use of ZnO nanoparticles (NPs) in the world consumer market has resulted in likelihood of exposure to human beings. The present study was aimed to assess the in vitro and in vivo interactions of ZnO NPs in the mammalian system and to elucidate the possible mechanism of their toxicity. Our in vitro results using human epidermal cells (A431), primary human epidermal keratinocytes and human liver cells (HepG2) demonstrated that cells exposed to ZnO NPs exhibit a decrease in cell viability which was independent of NP dissolution. ZnO NPs also induced oxidative DNA damage as evidenced by an increase in the Fpg sensitive sites. The reactive oxygen species triggered a decrease in mitochondrial membrane potential and an increase in the ratio of Bax/Bcl2 leading to apoptosis through the intrinsic pathway. In addition, ZnO NPs induced phosphorylation of JNK, P38 and P53ser15. The results from our in vivo studies using a mouse model showed that ZnO NPs induce lipid peroxidation, oxidative DNA damage and apoptosis in liver which further confirmed our in vitro findings. The data from the present study provide valuable insights into the cellular interactions of ZnO NPs and the underlying molecular mechanism of their toxicity. The results also stress the need for a comprehensive environmental health and safety assessment of engineered nanomaterials to ensure safer nanotechnology based products.

Zhu, Jinyong. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 128-139). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Chau, Kin Fan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 106-119). / Abstract also in Chinese. / Abstract --- p.II / 摘要 --- p.VI / Acknowledgements --- p.IX / List of figures --- p.X / List of Abbreviations --- p.XII / Table of Contents --- p.XV / Chapter Chapter 1: --- Introduction / Chapter 1.1 --- Incidence and etiology of hepatocellular carcinoma (HCC) --- p.1 / Chapter 1.2 --- Structure of Hepatitis B Virus (HBV) --- p.2 / Chapter 1.3 --- Hepatitis B X protein (HBx) and HCC --- p.5 / Chapter 1.4 --- HBx and Apoptosis --- p.8 / Chapter 1.5 --- The role of Bcl-2 family in apoptosis and cell survival --- p.10 / Chapter 1.6 --- "Bid, the BH3-domain only protein" --- p.14 / Chapter 1.7 --- Dual Functions of Bid --- p.16 / Chapter 1.8 --- The relationship between Bid and HBx --- p.19 / Chapter 1.9 --- Hypoxia and HCC --- p.21 / Chapter 1.10 --- Hypoxia and HBx --- p.25 / Chapter 1.11 --- Hypoxia and Bid --- p.28 / Chapter 1.12 --- Aim of study --- p.29 / Chapter Chapter 2: --- Methods and materials / Chapter 2.1 --- Confirmation of the culture of the stable cell lines --- p.30 / Chapter 2.2 --- Doxorubicin treatment to the cell lines --- p.34 / Chapter 2.3 --- Culture of the cell lines under hypoxic conditions --- p.35 / Chapter 2.4 --- Protein sample preparations --- p.37 / Chapter 2.5 --- Determination of protein samples --- p.38 / Chapter 2.6 --- Sodium dodecyl sulfate 226}0ؤ polyacrylamide gel electrophoresis (SDS- PAGE) --- p.39 / Chapter 2.7 --- Transfer of protein to nitrocellulose membranes --- p.39 / Chapter 2.8 --- Western blot analysis of proteins --- p.41 / Chapter 2.8.1. --- Antibodies --- p.41 / Chapter 2.8.2. --- Determination of expression profiles of desired proteins by immunoblotting --- p.45 / Chapter 2.9 --- "Measurement of cell viability by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay" --- p.46 / Chapter 2.10 --- Determination of cell proliferation by BrdU proliferation assay --- p.47 / Chapter 2.11 --- Detection of apoptosis of the cell lines by TUNEL (Terminal deoxynucleotidyl transferase mediated dUTP Nick End Labeling) --- p.50 / Chapter 2.12 --- Determination of the involvement of p38 MAPK in the generation of truncated Bid by p38 MAPK inhibitor SB203580 --- p.52 / Chapter Chapter 3: --- Results / Chapter 3.1 --- Confirmation of plasmids and the stable cell lines --- p.53 / Chapter 3.2 --- Morphology and the basic parameters of the cells with full-length HBx or mutant HBx --- p.53 / Chapter 3.3 --- Cell viability under doxorubicin treatment with or without hypoxia --- p.59 / Chapter 3.4 --- Determination of cell proliferation under stress --- p.70 / Chapter 3.5 --- Expression profiles of various proteins in the stable cell lines under doxorubicin treatment with or without hypoxia --- p.74 / Chapter 3.5.1. --- Verification of hypoxia --- p.74 / Chapter 3.5.2. --- Pro-apoptotic proteins --- p.74 / Chapter 3.5.3. --- Anti-apoptotic proteins --- p.74 / Chapter 3.6 --- Determination of apoptosis of various cell lines under stress --- p.82 / Chapter 3.7 --- "p38 MAPK, but not Akt, was activated by doxorubicin" --- p.87 / Chapter 3.8 --- The p38 MAPK inhibitor SB203580 could attenuate the cleavage of Bid --- p.89 / Chapter Chapter 4: --- Discussion --- p.92 / Chapter Chapter 5: --- Conclusion and future prospective --- p.103 / Chapter Chapter 6: --- References --- p.106

THE ASSESSMENT OF INFLUENCE OF ZINC IONS AND ECHINACEA PURPUREA (L.) MOENCH FOR MICE INTOXICATED BY CADMIUM IONS Abstract Background. Cadmium (Cd), a well-known environmental hazard, exerts a number of toxic effects in organism. It disturbs the activity of biochemical systems of cells. Accumulation of cadmium depends on the amount of essential trace elements, including zinc. Echinacea purpurea (L.) Moench (EP) can modify its influence. The aim of the study was to assess the influence of ions of cadmium, zinc, and EP on organism in experimental model of mice. The objectives of the scientific work were as follows: 1. To evaluate the accumulation of cadmium in the internal organs of experimental mice after acute and chronic intraperitoneal and per oral intoxication. 2. To assess morphological changes in liver tissue, mitotic and apoptotic activity of liver cells after the intoxication by cadmium ions of different duration and dose. 3. To assess the effect of zinc ions to the accumulation of cadmium in the internal organs and to the mitotic and apoptotic activity of liver cells in the organism of mice intoxicated by cadmium. 4. To evaluate the effect of EP to accumulation of cadmium in internal organs, mitotic and apoptotic activity of liver cells after the chronic intraperitoneal and per oral intoxication by cadmium ions. The scientific novelty of the study. This work makes our knowledge about mechanisms and outcomes of acute and chronic exposure to cadmium deeper. The... [to full text]

Liver progenitor cells (LPCs) play a major role in the regeneration process following chronic liver damage. LPCs can differentiate into hepatocytes and cholangiocytes and thus are capable of replenishing the damaged liver. Due to their plasticity and robust nature in culture systems, they are promising candidates for use in cell therapy. However, to be able to use LPCs as tissue regenerating stem cell-like cells in the clinic, we need to fully understand how they are controlled. Although a strong association between LPCs and inflammation has been shown in many chronic liver diseases, the role of the immune system in LPC-mediated hepatic regeneration is poorly understood. We hypothesise that specific immune cells and mediators are needed to induce the LPC compartment, and that these are common to the LPC response in different injury settings. Therefore, the present study focused on the characterisation of the inflammatory environment in the LPC response, which generates this niche. The aims of this study were (i) to identify the immune cells that are important for the LPC response, (ii) to define the cytokine profile and (iii) to determine the role of the cytokine producing cells during liver regeneration. To study hepatic inflammation following liver injury, a diet-induced model of liver injury (choline-deficient, ethionine-supplemented diet, CDE diet) was compared to two transgenic mouse models of immune-mediated hepatitis (Met-Kb, 178.3). Although all three models are characterised by hepatitis, histological analysis revealed that LPCs were only detectable in the CDE and Met-Kb livers. In the 178.3 model, livers regenerated from proliferating hepatocytes. An LPC response could not be induced in these mice even when liver damage was made more severe. In the other two models, LPC numbers increased over time showing the highest numbers one week after the peak of liver injury. LPCs were often found in close proximity to inflammatory cells, in particular macrophages.

Aujourd’hui, la transplantation est le seul traitement efficace proposé aux patients souffrant d’une insuffisance hépatique fulminante. La nécessité de disposer d’un système de suppléance hépatique transitoire apparaît donc indispensable. C’est dans cet axe que se sont développés les systèmes qualifiés de foies bio artificiels (BAL). Leur principale caractéristique est d’incorporer un bioréacteur hébergeant des cellules pouvant restaurer l’activité hépatiques dans son ensemble. A l’heure actuelle, les hépatocytes primaire humains (HEP) issus de foies de donneurs non transplantables sont considérées comme le meilleur choix. Cependant, leur utilisation reste limitée par leur faible disponibilité et la difficulté à les maintenir différenciés en culture in vitro. Pour remédier à ce dernier point, l’approche la plus prometteuse semble être une co-culture des hépatocytes avec les cellules non parenchymateuses afin de recréer un environnement proche des sinusoïdes hépatiques. Ce travail de thèse repose sur la mise en place d’une nouvelle approche de co-culture tridimensionnelle sous la forme de sphéroïdes, d’HEP primaires avec les principaux types de cellules non-parenchymateuses (les cellules de Kupffer, les cellules endothéliales et les cellules étoilées) selon des proportions spécifiques. Puis de leurs encapsulations dans des billes d’alginate et leurs cultures au sein d’un bioréacteur à lit fluidisé. Ce modèle s’est révélé pertinent et approprié à maintenir les fonctions hépatiques dans le temps. Bien que beaucoup d’optimisation reste à définir, ce travail exploratoire témoigne de l’intérêt de cette approche intéressante pour le progrès des systèmes BAL. / Liver shortage makes transplantation inapplicable to all acute liver failure patients. Bioartificial Iiver (BAL) devices represent a temporary solution for these patients which are thereby bridged tilt Iiver transplantation or regeneration BAL treatment offers blood purification and substitution of metabolic functions through the activity of hepatocytes (HEPs), which are integrated in the device within acclimating containers, so-called bioreactors. Primary human hepatocytes are the ideal cell type to use in BAL, but they are scarcely available and difficult to maintain in vitro. Co-culture of HEPs with supporting cells has been proposed as the most promising strategy for preserving HEP behaviors in in vitro conditions. In fact, assisting cells types hold their ability to influence functional responses of the HEPs by providing them with cues of the native organ.This PhD work proposed a novel approach of co-culture for the functional sustain and preservation of the HEPs in the environment of the fluidized bed bioreactor (designed in our Iaboratory). Definition of this model took inspiration from the cellular organization in the organ; therefore, it employed three major sinusoidal non-parenchymal cell populations (liver sinusoidal, Kupffer, and hepatic stellate cells) which, together with HEPs, were cultured with three-dimensional arrangement (spheroids) and according to specific proportions. The resulting model was characterized in terms of functional benefits for the HEPs, and then applied in the microenvironment of alginate beads, which provide cells with immunological and mechanical protection in the fluidized bed bioreactor. This spheroidal multi-cultured model revealed its potentiality in sustaining in vitro HEP behaviors over time. Although much remains to be refined, this model may represent an interesting approach for the progress of BAL

L’objectif prioritaire de ce travail était de provoquer un état de tolérance immunologique à des allogreffes cardiaques et cutanées chez des souris injectées avec des cellules souches hématopoïétiques (CSH) transduites avec le gène de l’interleukine 10. Un deuxième but était d’améliorer la survie des greffons cutanés en utilisant des cellules dendritiques immatures tolérogène. Le foie fœtal de souris contient en moyenne 2% de cellules souches capables de se différencier dans toutes les lignées hématolymphoïdes. De plus, leur relativement faible expression des antigènes du CMH fait d’elles un matériel biologique parfois susceptible de s’adapter à un environnement allogénique. L’IL-10 est une cytokine anti-inflamatoires. Produite par les lymphocytes Th2 principalement, elle inhibe la production de cytokines pro-inflamatoires telle l’IL-2. Elle empêche aussi la fonction de présentation des antigènes des CPA. Les cellules dendritiques (DC) dérivent de CSH, elles jouent un rôle central dans l’immunité et sont capables d’interagir avec les cellules du système immunitaire inné et adaptatif. Elles sont essentielles à la mise en place d’une réponse régulatrice ou tolérogène, ceci en fonction des informations fournies par le microenvironnement cellulaire. Les résultats montrent d’une part que les CSH fœtales, de souris C57 BL/6 transduites avec le gène de l’IL-10 et injectées plusieurs fois à des souris allogéniques (BALB/c), induisent une prolongation de survie du greffon cardiaque de même souche. Cette survie est de 86.25+13.8 jours versus 11.5+0.6 jours pour les groupes contrôles. Les DC tolérogènes (tol-DC) de souris DBA1 traitées avec le TNFα sont injectées à des souris allogéniques (BALB/c). Il en résulte une prolongation de survie du greffon cutané de même souche que les tol-DC : 15 jours vs 7.5 jours pour les contrôles. Seuls les animaux transplantés avec des tol-DC présentent un état de tolérance autorisant la prolongation de la survie de greffonsallogéniques / The main objective of this work was to induce a state of immunological tolerance to cardiac and skin allografts in mice injected with hematopoietic stem cells (HSCs) transduced with the gene for interleukin 10 (IL-10). A second goal was to improve the survival of skin grafts using immature dendritic cells well known for their tolerogenic function. Mouse fetal liver contains 2% of stem cells on average that can differentiate into all blood-lymphoid lineages. In addition, their relatively low antigen expression of major histocompatibility complex (MHC) makes them a biological material sometimes capable to adapt to an allogeneic environment. IL-10 is a cytokine with anti-inflammatory properties. Mainly produced by Th2 lymphocytes cells, IL-10 inhibits the production of pro-inflammatory cytokines such as IL-2. It prevents antigen presenting function of APCs. Dendritic cells (DC) derived from HSCs and play a central role in immunity. They are able to interact with cells of the innate and adaptive immune system. They are essential to the establishment of a regulatory or tolerogenic response, this based on the information provided by the cellular microenvironment. Results firstly show that fetal HSC of C57 BL/6 mice transduced with IL-10 gene and injected several times to allogeneic mice (BALB/c) sublethally irradiated induce a prolongation of heart transplant survival of the same strain. This survival is of 86.25+13.8 days in comparison with 11.5+0.6 days for control groups. Tolerogenic dendritic cells (tol-DC) of DBA1 mice treated with TNFα are injected into allogeneic mice (BALB/c) sublethally irradiated. This results in a prolongation of skin graft survival of same strain as tol-DC: 15 days compared to 7.5 days for the control groups. Only tol-DC transplanted animals have a tolerance state allowing prolonged survival of allogeneic skin grafts

出版日2016/2/15を明示する必要あり。発行号・ページ数が決まっていればそれらも明示する必要あり。 Final publication is available at http://dx.doi.org/10.3727/096368916X690999 / 京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19925号 / 医博第4145号 / 新制||医||1017(附属図書館) / 33011 / 京都大学大学院医学研究科医学専攻 / (主査)教授 長船 健二, 教授 伊達 洋至, 教授 坂井 義治 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM