published_or_final_version / Zoology / Doctoral / Doctor of Philosophy

Leung Yiu Kwong, Michael. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 155-161). / Acknowledgements --- p.i / Abbreviations --- p.ii / Aim and scope of this dissertation --- p.v / Abstract --- p.vi / Table of contents --- p.viii / Introduction --- p.1 / Chapter 1.1 --- Introduction --- p.2 / Chapter 1.2 --- Tumor Biology --- p.3 / Chapter 1.3 --- The Defence Mechanisms --- p.4 / Chapter 1.3.1 --- Non-specific defence mechanisms --- p.5 / Chapter 1.3.2 --- Specific defence mechanisms --- p.6 / Chapter 1.4 --- Effector Mechanisms in Anti-tumor Immunity --- p.7 / Chapter 1.4.1 --- B-cell --- p.8 / Chapter 1.4.2 --- "Natural killer (NK) cells (Non-T, Non-B)" --- p.8 / Chapter 1.4.3 --- Macrophages --- p.9 / Chapter 1.4.4 --- Cytolytic T-lymphocytes (CTLs) --- p.10 / Chapter 1.5 --- Cancer Treatment --- p.10 / Chapter 1.5.1 --- Surgery --- p.10 / Chapter 1.5.2 --- Radiotherapy --- p.12 / Chapter 1.5.3 --- Drug therapy --- p.12 / Chapter 1.5.4 --- Gene therapy --- p.13 / Chapter 1.5.5 --- lmmunotherapy --- p.13 / Chapter 1.6 --- Non-cytotoxic Antitumor Polysaccharides of Fungi --- p.14 / Chapter 1.6.1 --- Yeast polysaccharides --- p.14 / Chapter 1.6.2 --- Lichen polysaccharides --- p.15 / Chapter 1.6.3 --- Fungal polysaccharides --- p.18 / Chapter 1.7 --- Fungi and their Polysaccharides --- p.20 / Chapter 1.7.1 --- Reserve carbohydrates --- p.20 / Chapter 1.7.2 --- Structural polysaccharides --- p.21 / Chapter 1.8 --- The Architecture of the Fungal Cell Wall --- p.22 / Materials and Methods --- p.26 / Chapter 2.1 --- Materials --- p.27 / Chapter 2.1.1 --- Animals --- p.27 / Chapter 2.1.2 --- Mushrooms --- p.27 / Chapter 2.1.3 --- "Buffers, culture media and chemicals" --- p.27 / Chapter 2.1.4 --- Cell lines --- p.34 / Chapter 2.2 --- Methods --- p.35 / Chapter 2.2.1 --- Screening of β-(l→3)-D-glucan --- p.35 / Chapter 2.2.2 --- Extraction and Fractionation of Flammulina velutipes --- p.35 / Chapter 2.2.3 --- Characterisation of Flammulina velutipes --- p.38 / Chapter 2.2.3.1 --- The determination of carbohydrate content of F.V fractions --- p.38 / Chapter 2.2.3.2 --- The determination of protein content of F.V. fractions --- p.39 / Chapter 2.2.3.3 --- The determination of uronic acid content of F.V fractions --- p.39 / Chapter 2.2.3.4 --- The determination of component sugar units of F.V fractions --- p.39 / Chapter 2.2.3.5 --- Periodate uptake of F.V. fractions --- p.40 / Chapter 2.2.3.6 --- Limulus amebocyte lysate (LAL) coagulation assay --- p.40 / Chapter 2.2.3.7 --- The digestion of F.V. fractions with laminarinase --- p.41 / Chapter 2.2.3.8 --- The Secondary and tertiary structure determination of FH and SFA1 --- p.42 / Chapter 2.2.3.9 --- Molecular weight estimation of FH and SFA1 --- p.43 / Chapter 2.2.3.10 --- Vascular dilation and hemorrhage (VDH) activity of F.V. fractions / Chapter 2.2.4 --- Isolation and preparation of cells --- p.43 / Chapter 2.2.4.1 --- Bone marrow cell --- p.43 / Chapter 2.2.4.2 --- Peritoneal exudate cell (PEC) --- p.44 / Chapter 2.2.4.3 --- Splenocytes --- p.44 / Chapter 2.2.4.4 --- Depleting mouse T-cells by anti-mouse T-cell antigen antibody plus complement treatment --- p.45 / Chapter 2.2.4.5 --- Depleting mouse B-cells by Cedarlane column kit --- p.45 / Chapter 2.2.5 --- Assays for the cytotoxicity of Flammulina velutipes --- p.45 / Chapter 2.2.5.1 --- Brine shrimp assay --- p.45 / Chapter 2.2.5.2 --- In vitro cytotoxicity of FH and SFA1 on bone marrow cells of female BALB/c mice --- p.46 / Chapter 2.2.5.3 --- In vivo cytotoxicity of FH and SFA1 on female BALB/c mice --- p.47 / Chapter 2.2.6 --- "Assays for the immunomodulatory activities of Flamm""lina velutipes" --- p.47 / Chapter 2.2.6.1 --- In vitro mitogenic activities of FH and SFA1 on murine lymphocytes --- p.47 / Chapter 2.2.6.2 --- In vitro mitogenic activities of FH and SFA1 with PMB on murine lymphocytes --- p.48 / Chapter 2.2.6.3 --- In vitro mitogenic activities of FH and on T-cell depleted murine lymphocytes --- p.48 / Chapter 2.2.6.4 --- In vitro mitogenic activities of FH on B-cell depleted murine lymphocytes --- p.49 / Chapter 2.2.6.5 --- In vitro co-mitogenic activitiy of FH and SFA1 on murine lymphocytes --- p.49 / Chapter 2.2.6.6 --- In vitro mitogenic activities of FH and SFA1 on murine bone marrow cells --- p.50 / Chapter 2.2.6.7 --- In vivo mitogenic activities of FH and SFA1 on murine lymphocytes --- p.50 / Chapter 2.2.6.8 --- Effect of FH and SFA1 on the enhancement of first antibody production of SRBC immunised mice --- p.51 / Chapter 2.2.6.9 --- Effect of FM and SFA1 on the in vitro phagocytic activity of murine macrophage --- p.51 / Chapter 2.2.6.10 --- Effect of FM and SFA1 on the in vivo phagocytic activity of murine macrophage --- p.51 / Chapter 2.2.6.11 --- In vivo migration of macrophage in FH- and SFAl-treated mice --- p.53 / Chapter 2.2.6.12 --- Effect of FH and SFA1 on the enhancement of murine PEC cytostatic activity --- p.53 / Chapter 2.2.6.13 --- Effect of FH and SFA1 on the Fc receptor expression of peritoneal exudate cells --- p.54 / Chapter 2.2.6.14 --- Effect of FH and SFA1 on murine serum cytokine level --- p.55 / Chapter 2.2.6.15 --- Effect of FH and SFA1 on murine serum TNF level --- p.55 / Chapter 2.2.6.16 --- Effect of FH and SFA1 on the augmentation of SRBC lysing ability of murine serum --- p.56 / Chapter 2.2.7 --- Assays for the anti-tumor activities of Flammulina velutipes --- p.57 / Chapter 2.2.7.1 --- In vitro anti-tumor activity of FH and SFA1 --- p.57 / Chapter 2.2.7.2 --- Effect of FH and SFA1 on the growth of murine transplantable tumor invivo --- p.58 / Chapter 2.2.8 --- Statistical analysis --- p.59 / "Screening, Purification, Fractionation and Characterisation of β-(l→3)-D-glucan(s) from Flammulina velutipes" --- p.60 / Introduction --- p.61 / Results --- p.62 / Chapter 3.1 --- Screening of β-(l→3)-D-Glucan --- p.62 / Chapter 3.2 --- Extraction and Fractionation of Flammulina velutipes --- p.62 / Chapter 3.3 --- The Determination of Carbohydrate Content of F.V. Fractions --- p.65 / Chapter 3.4 --- The Determination of Protein Content of F.V. Fractions --- p.65 / Chapter 3.5 --- The Determination of Uronic Acid Content of F.V. Fractions --- p.69 / Chapter 3.6 --- The Determination of Component Sugar Units of F.V. Fractions --- p.69 / Chapter 3.7 --- Periodate Uptake of F.V. Fractions --- p.69 / Chapter 3.8 --- Limulus Amebocyte Lysate (LAL) Coagulation Assay --- p.73 / Chapter 3.9 --- The Digestion of F.V. Fractions with Laminarinase --- p.73 / Chapter 3.10 --- The Secondary and tertiary Structure Determination of FH and SFA1 --- p.80 / Chapter 3.11 --- Molecular Weight Estimation of FH and SFA1 --- p.82 / Chapter 3.12 --- "Vascular Dilation and Hemorrhage (VDH) Activity of FH, SFA1 and lFA1" --- p.82 / Discussion --- p.90 / The Toxicity of Flammulina velutipes --- p.96 / Introduction --- p.97 / Results --- p.97 / Chapter 4.1 --- Lack of Cytotoxicity of Flammulina velutipes to Brine Shrimp --- p.97 / Chapter 4.2 --- Lack of Cytotoxicity of Flammulina velutipes to Murine Bone Marrow Cells --- p.99 / Chapter 4.3 --- Lack of Cytotoxicity of Flammulina velutipes to Mouse --- p.99 / Discussion --- p.102 / The Immunomodulatory Activities of Flammulina velutipes --- p.103 / Introduction --- p.104 / Results --- p.105 / Chapter 5.1 --- Effect of Flammulina velutipes on Murine Lymphocytes --- p.105 / Chapter 5.2 --- Effect of Flammulina velutipes on Murine Macrophage --- p.115 / Chapter 5.3 --- Effect of Flammulina velutipes on Murine Serum Cytokine and Complement Level --- p.125 / Discussion --- p.133 / The Anti-tumor Activities of Flammulina velutipes --- p.136 / Introduction --- p.137 / Results --- p.137 / Chapter 6.1 --- In Vitro Anti-Tumor Activity of FH and SFA1 --- p.137 / Chapter 6.2 --- Effect of FH and SFAI on the Growth of Murine TransplantableTumors --- p.138 / Discussion --- p.145 / General Discussion --- p.146 / General Discussion and Future Perspectives --- p.147 / References --- p.154

Cette thèse s’inscrit dans le cadre de la recherche d’agonistes et d’antagonistes de récepteurs de chimiokines d’intérêt thérapeutique chez des champignons et des levures pathogènes pour l’homme ou l’animal. <p><p>Un screening préliminaire réalisé sur 88 souches de microorganismes a permis de sélectionner trois extraits de champignons présentant une activité compétitrice.<p><p>Des champignons Aspergillus ochraceus et Microsporum cookei, nous avons isolé une substance possédant une activité compétitrice sur le récepteur CCR5. Des chromatographies d’exclusion effectuées sur les lyophilisats des milieux conditionnés (CO.4) ont conduit à l’isolement d’une fraction active dont les constituants ont une masse moléculaire comprise entre 30 et 80 kDa. L’étude de ces substances n’a pas été poursuivie plus en détail.<p> <p>Par contre, de l’extrait dichlorométhane (CO.1) du champignon Trichoderma virens, nous avons isolé la gliotoxine [102] qui possède une activité antagoniste sur les récepteurs CCR2b et CCR5. Différents essais de culture de Trichoderma virens et d’Aspergillus fumigatus, connus pour synthétiser cette toxine, ont été entrepris en vue d’améliorer la quantité de gliotoxine produite. Malheureusement, ceux-ci n’ont pas abouti.<p> <p>A partir des faibles quantités de gliotoxine isolées, nous avons synthétisé deux analogues, la déthiogliotoxine [133] et la déhydrogliotoxine [134]. La comparaison des résultats des tests de compétition de ceux-ci sur le récepteur CCR2b démontre l’importance du pont disulfure pour l’observation de cette activité.<p> <p>Nous avons ensuite synthétisé les épidithiopipérazinediones (ETP) reprises ci-dessous, afin d’évaluer l’importance de cet élément structural pour l’activité compétitrice vis-à-vis des récepteurs CCR2b et CCR5.<p><p> \ / Doctorat en sciences, Spécialisation chimie / info:eu-repo/semantics/nonPublished