by Lam Kai Yi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 156-165). / Abstract also in Chinese. / Chapter Chapter One: --- Introduction --- p.1 / Chapter 1.1 --- Tumor Necrosis Factor-α in Cancer Treatment --- p.1 / Chapter 1.1.1 --- Historical Background --- p.1 / Chapter 1.1.2 --- Mechanisms of Action --- p.2 / Chapter 1.1.2.1 --- Production of Reactive oxidative Species / Chapter 1.1.2.2 --- Increase of Intracellular Free Calcium Concentration / Chapter 1.1.2.3 --- Activation of Ca2+/Mg2+-dependent Endonuclease / Chapter 1.1.2.4 --- Decrease of glucose uptake and Protein Synthesis / Chapter 1.1.2.5 --- Formation of Ion-permeable Channel / Chapter 1.1.2.6 --- Activation of Phospholipase / Chapter 1.1.2.7 --- Increase of S-phase Cells / Chapter 1.1.2.8 --- Immunomodulatory Effects / Chapter 1.1.3 --- Resistance of Cells to TNF-α --- p.7 / Chapter 1.1.4 --- Clinical Studies --- p.11 / Chapter 1.1.5 --- Side Effects --- p.12 / Chapter 1.2 --- Hyperthermia and Cancer Treatment --- p.14 / Chapter 1.2.1 --- Hyperthermic Agents --- p.15 / Chapter 1.2.2 --- Intrinsic Heat Sensitivity --- p.15 / Chapter 1.2.3 --- Mechanisms of Action --- p.17 / Chapter 1.2.3.1 --- Depolarization of Membrane Potential / Chapter 1.2.3.2 --- "Reduction of glucose transport and DNA, mRNA and Protein Synthesis" / Chapter 1.2.3.3 --- Decrease of Intracellular pH / Chapter 1.2.3.4 --- Calcium Imbalance / Chapter 1.2.3.5 --- Effect on Nucleolar Protein / Chapter 1.2.3.6 --- Apoptosis / Chapter 1.2.3.7 --- Induction of Autologous Tumor Killing / Chapter 1.2.3.8 --- "Blood Flow, Tumor Oxygenation and Vascular Damage" / Chapter 1.2.4 --- Clinical Studies --- p.20 / Chapter 1.3 --- Combined Treatment --- p.21 / Chapter 1.3.1 --- Combined Treatment with TNF-α and Fixed-temperature Hyperthermia --- p.22 / Chapter 1.3.2 --- Combined Treatment with TNF + Step-down Hyperthermia --- p.22 / Chapter 1.3.3 --- In Vivo Study --- p.23 / Chapter 1.3.4 --- Sequence of Treatment --- p.24 / Chapter 1.3.5 --- Proposed Mechanism of Synergism --- p.24 / Chapter 1.4 --- Objective of Study --- p.26 / Chapter 1.4.1 --- Sequence of Treatments --- p.26 / Chapter 1.4.2 --- Comparison of Treatments' Effectiveness --- p.27 / Chapter 1.4.3 --- Effect on Normal Cell --- p.27 / Chapter 1.4.4 --- Effect on Distribution of Cells in Cell Cycle Phases --- p.28 / Chapter 1.4.5 --- In Vivo Study --- p.28 / Chapter Chapter Two: --- Materials and Methods --- p.30 / Chapter 2.1. --- Materials --- p.30 / Chapter 2.1.1 --- For Cell Culture --- p.30 / Chapter 2.1.2 --- In vitro Treatments --- p.31 / Chapter 2.1.3 --- DNA Electrophoresis --- p.31 / Chapter 2.1.4 --- Flow Cytometry --- p.32 / Chapter 2.2. --- Reagent Preparation --- p.33 / Chapter 2.2.1 --- Culture Media --- p.33 / Chapter 2.2.2 --- Human Recombinant Tumor Necrosis Factor alpha (rhTNF-α) --- p.33 / Chapter 2.2.3 --- Phosphate Buffered Saline (PBS) --- p.33 / Chapter 2.2.4 --- Lysis Buffer --- p.34 / Chapter 2.2.5 --- TE Buffer --- p.34 / Chapter 2.2.6 --- Proteinase K and Ribonuclease A (RNase A) --- p.34 / Chapter 2.2.7 --- 100 Base-Pair DNA Marker --- p.34 / Chapter 2.2.8 --- Propidium Iodide (PI) --- p.35 / Chapter 2.3 --- Methods --- p.35 / Chapter 2.3.1 --- Cell Culture --- p.35 / Chapter 2.3.1.1 --- Ehrlich Ascitic Tumor (EAT) and Human Leukemia (HL-60) / Chapter 2.3.1.2 --- Human Coronary Artery Endothelial Cells (HCAEC) / Chapter 2.3.2 --- In vitro Experiments --- p.36 / Chapter 2.3.3 --- Tumor Necrosis Factor Treatment --- p.37 / Chapter 2.3.4 --- Hyperthermia Treatments --- p.37 / Chapter 2.3.5 --- Cell Counting --- p.38 / Chapter 2.3.5.1 --- Trypan Blue Exclusion Assay / Chapter 2.3.5.2 --- Neutral Red Assay / Chapter 2.3.6 --- Determination of Additive or Synergistic Effect --- p.39 / Chapter 2.3.7 --- DNA Electrophoresis --- p.40 / Chapter 2.3.8 --- Flow Cytometry --- p.42 / Chapter 2.3.7.1 --- Preparation of Samples / Chapter 2.3.7.2 --- Flow Cytometry Acquisition / Chapter 2.3.7.3 --- Analysis / Chapter 2.3.9 --- In vivo Experiments --- p.44 / Chapter 2.3.8.1 --- Animal Strain / Chapter 2.3.8.2 --- Cell Line / Chapter 2.3.8.3 --- Tumor Necrosis Factor Treatment / Chapter 2.3.8.4 --- Hyperthermia Treatments / Chapter 2.3.8.5 --- Test of Body Temperature / Chapter 2.3.8.6 --- Cell Harvesting / Chapter Chapter Three: --- Result --- p.50 / Chapter 3.1 --- Optimal Sequence of Treatments --- p.50 / Chapter 3.1.1 --- Optimal Sequence of Treatments on Murine Ehrlich Ascitic Tumor (EAT) cells --- p.50 / Chapter 3.1.1.1 --- TNF + Fixed-temperature Hyperthermia / Chapter 3.1.1.2 --- TNF + Step-down Hyperthermia2 / Chapter 3.1.1.3 --- TNF + Step-down Hyperthermia3 / Chapter 3.1.2 --- Optimal Sequence of Treatments on Human Leukemia cells HL-60 --- p.60 / Chapter 3.1.2.1 --- TNF + Fixed-temperature Hyperthermia / Chapter 3.1.2.2 --- TNF + Step-Down Hyperthermia2 / Chapter 3.1.2.3 --- TNF + Step-Down Hyperthermia3 / Chapter 3.2 --- Comparison of Effectiveness of Treatments --- p.72 / Chapter 3.2.1 --- Effectiveness of Various treatments on EAT cells --- p.72 / Chapter 3.2.2 --- Synergistic Effect between rhTNF-α and Hyperthermia on EAT cells --- p.74 / Chapter 3.2.3 --- Decrease of Relative Growth and Viability of EAT with Time --- p.79 / Chapter 3.2.3.1 --- TNF + Fixed-temperature Hyperthermia / Chapter 3.2.3.2 --- TNF + Step-down Hyperthermia2 / Chapter 3.2.3.3 --- TNF + Step-down Hyperthermia3 / Chapter 3.2.4 --- Comparison of Effectiveness of Various Treatments on HL-60 cells --- p.82 / Chapter 3.2.5 --- Synergistic Effect between rhTNF-α and Hyperthermia on HL-60 cells --- p.87 / Chapter 3.2.6 --- Change of Relative Growth and Viability of HL-60 with Time --- p.90 / Chapter 3.2.6.1 --- TNF + Fixed-temperature Hyperthermia / Chapter 3.2.6.2 --- TNF + Step-down Hyperthermia2 / Chapter 3.2.6.3 --- TNF + Step-down hyperthermia3 / Chapter 3.3 --- Cell Death Pathway --- p.96 / Chapter 3.3.1 --- Experiments on Ehrlich Ascitic Tumor (EAT) Cells --- p.96 / Chapter 3.3.2 --- Experiments on Human Leukemia (HL-60) Cells --- p.100 / Chapter 3.4 --- Experiment on Normal Cell --- p.104 / Chapter 3.5 --- Effect of TNF + Fixed-temperature Hyperthermia on the Cell Cycle Progression --- p.107 / Chapter 3.5.1 --- Different Times of TNF Administration and Distribution of EAT cells in Cell cycle --- p.107 / Chapter 3.5.2 --- Different Times of TNF Administration and Distribution of HL-60 cells in Cell Cycle --- p.114 / Chapter 3.5.3 --- Shift of Cells Cycle after TNF Treatment --- p.120 / Chapter 3.5.3.1 --- Response of Ehrlich Ascitic Tumor Cells / Chapter 3.5.3.2 --- Response of Human leukemia Cells / Chapter 3.6 --- Effectiveness of Treatments in vivo: --- p.129 / Chapter 3.6.1 --- Dose-dependent Response --- p.129 / Chapter 3.6.2 --- Change of Body Temperature During Hyperthermia --- p.131 / Chapter 3.6.3 --- Comparison of Effectiveness of Various Treatments in vivo --- p.133 / Chapter 3.6.4 --- Synergistic Effect Between rhTNF-α and Hyperthermia in vivo --- p.135 / Chapter Chapter Four: --- Discussion --- p.138 / Chapter 4.1 --- Optimal Sequence of Treatments --- p.139 / Chapter 4.2 --- Comparison of Various Treatments --- p.143 / Chapter 4.3 --- Distribution of Cells in Cell Cycle Phases --- p.149 / Chapter 4.4 --- In vivo Study --- p.153 / Chapter Chapter Five: --- References --- p.156

Type I diabetes (T1D) is an autoimmune disease characterized by the destruction of insulin-producing β cells in the pancreas. Destruction of the body's own proteins, cells, and tissues is precipitated by the dysfunction of cytokine production, protein modification, and signaling pathways in immune cell subtypes. Tumor Necrosis Factor α (TNFα) and its receptors Tumor Necrosis Factor 1 (TNFR1) also known as p55 and TNFRSF1A, and Tumor Necrosis Factor 2 (TNFR2) also known as P75 and TNFRSF1B play a crucial role in this autoimmune process. TNFα has been shown to stimulate cell death through TNFR1 signaling by the caspase system, while promoting cell survival through TNFR2 signaling using the Nuclear Factor Kappa-Light-Chain-Enhancer of Activated B cells (NF-𝜅B) pathway. Recent findings show a defect in immuno-proteasomes found in autoreactive T cells in people with T1D. This defect causes improper signaling transduction when TNFα binds to TNFR2. The inability to save the cell by activating the NF-𝜅B pathway eventually leads instead to apoptosis using the caspase system. A decrease in TNFα or increase in soluble TNFα receptors might be an explanation for these autoreactive T cells to evade the host immune system, and allow them to cause destruction of the pancreas. We hypothesize that patients with T1D will show abnormal distribution of TNFα and its receptors at basal levels, as well as when stimulated with interleukins, cytokines, and bacteria such as interleukin-2 (IL-2), lipotechoic acid (LTA), granulocyte macrophage-colony stimulating factor (GM-CSF), and Bacillus Calmette-Guérin (BCG). To test this hypothesis, we obtained peripheral blood from T1D patients (n=102) and controls (n=89) and performed in vitro stimulation assays. After a 48-hour incubation, tissue culture supernatants were collected and analyzed for TNF and its receptors production by ELISA, as well as densities of cell membrane receptors by flow cytometry. The data from this study showed significant differences in basal levels of TNFα, TNFR1, and TNFR2 on both the membrane and in the serum between patients and controls. Patients contained a greater percentage of CD4, 8, and 14 - TNFR2 and not TNFR1 double positive cells than their healthy control counterparts. Patient's sera also contained higher levels of all three markers, sTNFα, sTNFR1, and sTNFR2 than the controls. However, no significant differences were found between patient and controls when stimulated with the various compounds listed above.

by Li Jian Yi. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (p. 157-181). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

有證據顯示基質細胞在腫瘤的發生發展中可以發揮重要的作用，基質細胞可以提供適宜腫瘤細胞增殖的腫瘤微環境。腫瘤相關成纖維細胞是一種特殊的與腫瘤生成高度相關的基質細胞。而通过我们的论证，小鼠胚胎成纖維細胞可以作為一種腫瘤相關成纖維細胞的細胞模型。 / 腫瘤誘導因子（TIF）是本實驗室在成瘤實驗中發現的一種新的倉鼠CXC 趨化因子。基于蛋白質序列的分析，TIF 属于Gro CXC 趨化因子家族。這個家族主要通過激活其受體CXCR2 來發揮作用。為了研究TIF 在腫瘤發生中的作用，我們在CHO-K1 細胞中建立了過表達TIF 的穩定細胞株。 / 我們發現共同注射的永生化MEF 與過表達TIF 的D12 細胞導致了腫瘤生長的抑制。為了研究這種現象，重組TIF 蛋白在大腸桿菌中表達，并且用鎳柱進行了提純。純化的蛋白被用于處理CHO-K1 細胞與永生化MEF。我們發現高水平的TIF 可以導致CXCR2 下游的Erk 磷酸化水平下降。其可能的機制為CXCR2 在高水平的TIF 作用下的脫敏作用。同時高水平TIF 可以導致永生化MEF 中CD133 水平的下降。因此，CXCR2 脫敏為TIF 導致腫瘤抑制的可能機制。 / Lines of evidence indicate that stromal cell is one of the determinants in tumor formation by providing a favorable microenvironment for the growth of cancer cells. Cancer associated fibroblast (CAF) is a special form of stromal cells which are shown to be derived from bone marrow. Upon reaching the tumor, the bone marrow-derived mesenchymal stem cells differentiate into CAF, which secrets various growth factors and cytokines to promote cancer growth. Furthermore, genetic study shows that CAF displays p53 mutations and other genetic changes. / Tumor induced factor (TIF) is a CXC chemokine that is originally identified from a xenograft tumor. Sequence analysis suggests TIF is a family member of the Gro CXC chemokines, and exerts its cellular function via activating CXCR2 receptors. In order to investigate the functional roles of TIF, a stable cell line over-expressing TIF in hamster CHO-K1 was established. / To explore the cancer-stromal interactions in xenograft, mouse embryonic fibroblast (MEF) were used as a study model for CAF. MEF was sub-cultured by a conventional protocol that was used for developing the NIH3T3 cells. Based on the growth patterns and expressions of cell markers, growth of MEF can be divided into three stages: the early stage, the senescent stage and the immortalized stage. Our results suggested that MEF might mirror the various developmental stages of CAF. / To examine the contributions of MEF in tumorigenesis, CHO-K1 cells and MEF were co-injected into nude mice. Intriguingly, MEF that in senescent and immortalized stages, rather than in early stage, promoted tumor formation. A possibility arose that the contribution of senescent and immortalized MEF in promoted tumorigenesis may due to CD133 and CXCL1, as the expression of CD133 and CXCL1 in senescent and immortalized MEF were higher than that of MEF in early stage. Moreover, as MEF could gradually develop into a fibroblast promoted tumor formation, MEF could be used as a crucial model to illustrate the origination and development of CAF. / Surprisingly, in nude mice co-injected with immortalized MEF with TIF-overexpressing D12 cells, suppression instead of promotion of tumor growth was found. In order to explore the underlined mechanism of tumor suppression, recombinant TIF protein was purified based on a bacterial expression system. Using purified TIF protein to treat CHO-K1 cells and MEF, it was found that low concentration of TIF promoted Erk phosphorylation but high concentration of TIF suppressed it, which might resulted from desensitization of CXCR2 receptors. Reduction of Erk phosphorylation resulted in decreased proliferation in CHO-K1 cells and alleviated expression of CD133 in MEF, which could be the mechanisms for TIF-induced tumor suppression in nude mice. / Taken together, a CAF model was established to examine the function of TIF in tumor-fibroblast interactions. Mechanistic studies indicated that TIF-induced tumor suppression in nude mice was mediated via desensitization of CXCR2 receptors by high concentration of TIF in the tumor microenvironment. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Qi, Wei. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 189-206). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Tumorigenesis --- p.4 / Chapter 1.1.1 --- Virus transformation --- p.4 / Chapter 1.1.2 --- Proto-oncogene and oncogene --- p.5 / Chapter 1.1.3 --- Tumor suppressor gene --- p.7 / Chapter 1.1.4 --- Epigenetic alteration --- p.9 / Chapter 1.1.5 --- Cancer stem cell --- p.11 / Chapter 1.1.6 --- Tumor microenvironment --- p.14 / Chapter 1.2 --- Cancer associated fibroblast (CAF) --- p.17 / Chapter 1.2.1 --- Markers for CAF --- p.17 / Chapter 1.2.2 --- CAF and normal fibroblast --- p.20 / Chapter 1.2.3 --- CAF, a important player in tumor growth --- p.22 / Chapter 1.2.4 --- CAF and angiogenesis --- p.23 / Chapter 1.2.5 --- CAF and tumor invasion --- p.25 / Chapter 1.3 --- Chemokine --- p.27 / Chapter 1.3.1 --- Structure of chemokine --- p.27 / Chapter 1.3.2 --- Chemokine and cell Recruitment --- p.30 / Chapter 1.3.3 --- Chemokine and tumor microenvironment --- p.30 / Chapter 1.4 --- Tumor Induced Factor and its induced tumor suppression --- p.38 / Chapter 1.5 --- The aims of the project --- p.47 / Chapter Chapter Two --- Purification of Tumor Induced Factor / Chapter 2.1 --- Introduction --- p.49 / Chapter 2.2 --- Materials --- p.52 / Chapter 2.2.1 --- Chemical --- p.52 / Chapter 2.2.2 --- Enzyme --- p.52 / Chapter 2.2.3 --- Antibody --- p.52 / Chapter 2.3 --- Method --- p.53 / Chapter 2.3.1 --- Overview of protein expression system --- p.53 / Chapter 2.3.2 --- Purification of Trx-His₆-S-TIF protein --- p.54 / Chapter 2.3.3 --- BCA assay --- p.60 / Chapter 2.3.4 --- SDS-PAGE --- p.60 / Chapter 2.3.5 --- Western blotting --- p.61 / Chapter 2.3.6 --- Preparation of pET28/His₆-Sumo-TIF bacterial expression vector --- p.62 / Chapter 2.3.7 --- Optimization of culture condition for BL21 expressed His₆-Sumo-TIF protein --- p.67 / Chapter 2.3.8 --- Purification of His₆-Sumo-TIF protein --- p.68 / Chapter 2.3.9 --- Homology model of TIF --- p.68 / Chapter 2.4 --- Results --- p.69 / Chapter 2.4.1 --- Purification of Trx-His₆-S-TIF --- p.70 / Chapter 2.4.2 --- Optimization of purification protocol of His₆-Sumo-TIF --- p.71 / Chapter 2.4.3 --- Large scale purification of mature TIF --- p.75 / Chapter 2.4.4 --- Homology modeling of TIF --- p.80 / Chapter 2.5 --- Discussion --- p.83 / Chapter Chapter 3 --- Three Stages Hypothesis / Chapter 3.1 --- Introduction --- p.86 / Chapter 3.2 --- Material --- p.93 / Chapter 3.2.1 --- Chemical --- p.93 / Chapter 3.2.2 --- Enzyme --- p.93 / Chapter 3.2.3 --- Animal --- p.93 / Chapter 3.2.4 --- Antibody --- p.94 / Chapter 3.3 --- Methods --- p.95 / Chapter 3.3.1 --- Isolate MEF from 13.5 days mouse embryo --- p.95 / Chapter 3.3.2 --- Culture of MEF following 3T3 protocol --- p.96 / Chapter 3.3.3 --- X gal staining --- p.96 / Chapter 3.3.4 --- Analysis of MEF cell size and complexity by flow cytometry --- p.98 / Chapter 3.3.5 --- MTT assay --- p.98 / Chapter 3.3.6 --- Analysis of CD133 by flow cytometry --- p.99 / Chapter 3.3.7 --- ROS detected by DCFH-DA fluorescent probe --- p.99 / Chapter 3.3.8 --- Double staining of cancer stem cell marker and ROS fluorescent probe --- p.100 / Chapter 3.3.9 --- Reverse transcription --- p.101 / Chapter 3.3.10 --- Analysis CXCL1 mRNA expression level by PCR --- p.102 / Chapter 3.3.11 --- Gelatin zymography --- p.103 / Chapter 3.3.12 --- In-vivo tumorigenicity assay --- p.104 / Chapter 3.4 --- Results --- p.106 / Chapter 3.4.1 --- Three Stages of MEF --- p.106 / Chapter 3.4.2 --- X gal staining --- p.106 / Chapter 3.4.3 --- Flow cytometric analysis of cell diameter and cellular complexity of MEF --- p.109 / Chapter 3.4.4 --- MTT assay --- p.109 / Chapter 3.4.5 --- CD 133 expression of MEF detected by flow cytometry --- p.110 / Chapter 3.4.6 --- Reactive oxygen species of MEF detected by flow cytometry --- p.118 / Chapter 3.4.7 --- The level of ROS and CD133 of MEF detected by flow cytometry stimultaneously --- p.121 / Chapter 3.4.8 --- TIF treatment reduces the small CSC subpopulation in senescent stage MEF --- p.124 / Chapter 3.4.9 --- Increased CXCL1 expression in senescent stage and immortalized stage MEF --- p.125 / Chapter 3.4.10 --- Matrix metalloproteinase 2 activities in different stages of MEF . --- p.129 / Chapter 3.4.11 --- In vivo tumorigenicity assay --- p.130 / Chapter 3.5 --- Discussion --- p.133 / Chapter Chapter Four --- Biphasic Effect of TIF in Cancer-Fibroblasts Interaction / Chapter 4.1 --- Introduction --- p.140 / Chapter 4.2 --- Material --- p.143 / Chapter 4.2.1 --- Chemical --- p.144 / Chapter 4.2.2 --- Kit and Instrument --- p.144 / Chapter 4.2.3 --- Antibody --- p.144 / Chapter 4.3 --- Method --- p.145 / Chapter 4.3.1 --- Purification of TIF-His₆-Flag --- p.145 / Chapter 4.3.2 --- Western blotting to detect purified TIF-His₆-Flag --- p.145 / Chapter 4.3.3. --- Measurement of cell proliferation by cell counting --- p.145 / Chapter 4.3.4 --- MTT assay --- p.146 / Chapter 4.3.5 --- Western blotting to detect pErk and total Erk --- p.146 / Chapter 4.3.6 --- Soft agar assay --- p.148 / Chapter 4.3.7 --- Gelatinase detection --- p.148 / Chapter 4.3.8 --- Wound healing assay --- p.149 / Chapter 4.3.9 --- Colony formation assay --- p.149 / Chapter 4.3.10 --- Detection of CD133 by flow cytometry --- p.150 / Chapter 4.4 --- Results --- p.151 / Chapter 4.4.1 --- Purification of TIF-His₆-Flag --- p.151 / Chapter 4.4.2 --- Reduced cell proliferation of D12 in long time culture --- p.153 / Chapter 4.4.3 --- Reduced metabolic activities of D12 cells in time culture --- p.155 / Chapter 4.4.4. --- TIF-CXCR2-pErk signal axis in CHO cells --- p.155 / Chapter 4.4.5 --- Bigger colonies formed by D12 cells in soft agar assay --- p.161 / Chapter 4.4.6 --- TIF-CXCR2-pErk-MMP9 signal pathway in D12 cells --- p.162 / Chapter 4.4.7 --- Reduced migration of D12 cells --- p.164 / Chapter 4.4.8 --- Reduced cell invasion of D12 cells --- p.165 / Chapter 4.4.9 --- Reduced colony number of D12 cells in colony formation assay --- p.168 / Chapter 4.4.10 --- Bi-phasic “bell shape“ bi-phasic response on Erk activation of TIF in CHO-K1 cells --- p.169 / Chapter 4.4.11 --- Bi-phasic “bell shape“ effect of TIF to pErk in immortalized MEFs --- p.172 / Chapter 4.4.12 --- Reduced CD133 in immortalized MEF by high concentration of TIF --- p.173 / Chapter 4.5 --- Discussion --- p.177 / Chapter Chapter Five --- General Discussion / Chapter 5.1 --- Project Summary --- p.183 / Chapter 5.2 --- Significances of the project --- p.185 / Chapter 5.3 --- Future work --- p.188

TNF defers apoptosis in macrophages undergoing spontaneous or pharmacologically (thapsigargin, ceramide, CCCP, etoposide or cisplatin)-induced apoptosis, as determined by measurements of caspase-3 activity and annexin-V staining (Chapter 2). The action requires TNF interaction with TNF-R1, not TNF-R2. Survival is uniquely reliant on the activity of the NF-B signaling pathway, and does not require activities arising from the PI3K/Akt, JNK, ERK, p38 MAP kinase or iNOS pathways (Chapter 3). Further, the general anti-apoptotic property of TNF and its specific antagonism of CCCP-induced apoptosis led to the finding that TNF action prevents cytochrome c release. This protection is likely mediated through effects on components of the MPTP itself, as TNF exhibited functional redundancy with the pore inhibitor cyclosporin A, and did not modify upstream events that promote MPTP opening during apoptosis, namely ROS production, cytosolic Ca2+ increase, or a reduction of total ATP (Chapter 4). Subsequent experiments with the mRNA synthesis inhibitor, actinomycin D, and the translation inhibitor, cycloheximide revealed that the protein(s) responsible for TNF-induced survival was transcribed and translated within 1 hr. However, western analyses provided no convincing evidence of the involvement of Mn-SOD, cIAP-1, XIAP, Bcl-2 or A1 in TNF cytoprotection (Chapter 5). Rather, microarray experiments identified the consistent induction of an early response gene, pim-1, within 30 min of TNF exposure (Chapter 6). This result was verified at the protein level with a specific Pim-1 antibody. Evidence was also found for induction of the anti-apoptotic protein A20, but only at mRNA level. Parthenolide, wortmannin, SP600125, PD98059, SB203580 or L-NAME1 acted against TNF-induced Pim-1 expression in a pattern that exactly matched the effects of these inhibitors on TNF-induced survival. That is, only parthenolide-mediated inactivation of NF-B abolished TNF-induced induction of Pim-1. TNF also stimulated the rapid phosphorylation (inactivation) of the pro-apoptotic BH3-only protein, Bad at Ser112 in a manner sensitive to NF-B inhibition, but not PI3K/Akt, JNK, ERK or p38 MAP kinase inhibition (Chapter 7). As Bad is a known substrate of Pim-1 and Bad 1 Parthenolide, wortmannin, SP600125, PD98059 and SB203580 are inhibitors of the NF-B, PI3K/Akt, JNK, ERK and p38 MAP kinase pathways, respectively. L-NAME inhibits iNOS. NF-B- and mitochondria-linked signaling events that contribute to TNF action in deferring physiological and chemotherapeutic drug-induced apoptosis in macrophages ii phosphorylation occurred coincident with Pim-1 upregulation, it is likely that Pim-1 kinase activity mediates the inactivation of Bad. The overall data therefore supports a model in which TNF ligation of TNF-R1 at the cell surface results in intracellular NF- B activation, leading to the induction of Pim-1 mRNA and protein, and the ensuing phosphorylation of Bad. Inactivation of pro-apoptotic Bad increases the resistance threshold of mitochondria to apoptotic insults, thereby reducing the occurrence of mitochondrial permeability transition, cytochrome c release and subsequent caspase-3 activation.

Abstract not available

Includes bibliographical references (leaves 182-240). Explores alternate strategies that may alter inflammatory cytokine production, particularly tumour necrosis factor đ [tumor necrosis factor-alpha], and therefore provide a possible treatment for rheumatoid arthritis.

Copies of author's previously published articles inserted. / Includes bibliographical references. / vii, 39 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Shows that the cytokine tumour necrosis factor [alpha] (TNF-[alpha]) enhances the adhesion of neutrophils to the endothelium by an action both on the neutrophil and on the endothelial cell. / Thesis (Ph.D.)--University of Adelaide, Dept. of Microbiology and Immunology, 1995?

Niemann-Pick Type C (NPC) disease is an autosomal recessive disorder that results in accumulation of unesterified cholesterol in late endosomes/lysosomes (LE/Ls), leading to progressive neurodegeneration and premature death. Microglia are resident immune cells of the central nervous system, which upon activation can secrete potentially neurotoxic molecules such as tumor necrosis factor-alpha (TNFα). Inappropriate activation of microglia has been implicated in NPC disease. Primary microglia cultures from the cerebral cortex of Npc1-/- mice have an altered cholesterol distribution characteristic of NPC-deficient cells. Immunocytochemical analysis revealed increased TNFα staining in Npc1-/- microglia. However, Npc1-/- and Npc1+/+ microglia showed similar mRNA levels of pro-inflammatory cytokines and similar levels of TNFα secretion. To determine whether Npc1-/- microglia contribute to neuron death in NPC disease, microglia were co-cultured with cerebellar granule cells. Surprisingly, the extent of neuronal death was the same in neurons cultured with Npc1+/+ or Npc1-/- microglia. Thus, Npc1-/- microglia have an altered phenotype compared to Npc1+/+ microglia, but this does not lead to neuron death in an in vitro co-culture system. Treatment options for NPC disease remain limited. A consequence of cholesterol sequestration in the LE/Ls, is that cholesterol movement to the endoplasmic reticulum, where cholesterol metabolism is regulated, is impaired. Cyclodextrin (CD), a compound that binds cholesterol, has recently been found to delay the onset of neurological symptoms and prolong life of Npc1-/- mice. Since the brain consists of both neurons and glia, it remains unclear if CD acts directly on neurons and/or other cells in the brain. Neurons cultured from the cerebellum and astrocytes cultured from the cortex of Npc1-/- mice were treated with a low dose (0.1mM) of CD. This treatment decreased cholesterol sequestration and decreased the rate of cholesterol synthesis in Npc1-/- neurons and astrocytes. CD also decreased mRNAs encoding proteins involved in cholesterol synthesis in Npc1-/- neurons and increased genes involved in cholesterol efflux in Npc1-/- astrocytes. Moreover, CD increased cholesterol esterification in Npc1-/- astrocytes. These results suggest that cholesterol trapped in LE/Ls in Npc1-/- neurons and astrocytes was released by CD treatment and reached the ER, thereby regulating cholesterol homeostasis. / Experimental Medicine

Thesis (Ph. D.)--University of Chicago, Committee on Immunology, June 2003. / Includes bibliographical references. Also available on the Internet.