• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • 1
  • 1
  • Tagged with
  • 3
  • 3
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Crystalline silica-induced inflammation

Mbatha, Nandi 17 November 2010 (has links)
M. Tech. / The persistent presence of neutrophils is associated with a wide range of inflammatory diseases. Resolution of inflammation in these diseases is also associated with the ingestion of apoptotic neutrophils by macrophages. Inflammation and apoptosis of inflammatory cells are common known features observed in the lung following exposure to crystalline silica. What is not known is how well these apoptotic cells are cleared by macrophages in the presence of crystalline silica? To investigate the latter, we incubated the U937 macrophages and neutrophils with crystalline silica and found that it could increase their apoptosis and necrosis especially those of the U937 cells. We then examined the ability of crystalline silica to induce the production of cytokines (TNF-α, IFN-γ and IL-1β) as well as NO by these cells. We found that these particles could increase the production of TNF-α, IL-1β and NO but not IFN-γ in a time-and concentration-dependent manner. We also assessed the ability of crystalline silica to alter the levels of GSH in neutrophils and U937 macrophages. We found that it could drastically decrease the levels of this antioxidant in U937 macrophages with no additional effect in neutrophils as these latter cells would have low levels of GSH prior to their incubation with crystalline silica. Finally, we examined the effect of crystalline silica on the ability of U937 macrophages to phagocytose apoptotic neutrophils. We found that while untreated U937 macrophages were able to phagocytose apoptotic neutrophils, the presence of crystalline silica reduced this ability by 15%. Taken together, our results suggest that exposure to crystalline silica impairs the clearance of apoptotic neutrophils by decreasing their phagocytosis by macrophages and thus prevents the resolution of inflammation.
2

Pattern recognition receptors and cytokine-mediated activation of human basophils: a novel link between innate immunity and allergic inflammation.

January 2013 (has links)
過敏性疾病(如過敏性哮喘和過敏性皮炎)發病率在香港及世界均呈上升趨勢。過敏性哮喘是一種慢性反復發作的炎症疾病,而過敏性皮炎是一種慢性皮膚炎症。呼吸道細菌及金黃色葡萄球菌可分別加重過敏性哮喘病人氣道炎症及過敏性皮炎患者的炎症反應。人體對細菌的先天免疫反應主要通過模式識別受體(PRR)介導。NOD樣受體(NLR)和Toll樣受體(TLR)是兩種重要的PRR。 NLR 家族成員NOD2幾乎識別所有細菌中結構保守的胞壁醯二肽(MDP)。而LTR2識別範圍廣泛的病原相關分子模式,如革蘭氏陽性菌中的肽聚糖(PGN)和脂磷壁酸(LTA),以及人工合成的脂蛋白Pam3CSK4。 / 本研究包括:NOD2配體MDP,哮喘相關的腫瘤壞死因子家族成員LIGHT對共培養的人嗜鹼性粒細胞和人支氣管上皮細胞的活化作用;熱滅活的金黃色葡萄球菌(HKSA),MDP,TLR2配體PGN,LTA,以及Pam3CSK4對共培養的人嗜鹼性粒細胞和人皮膚成纖維細胞的活化作用;在體內NLR配體對卵清蛋白(OVA)致敏的哮喘小鼠的作用。 / 研究發現,在共培養體系中,MDP能顯著增強嗜鹼性粒細胞與支氣管上皮細胞表面粘附因子(細胞間粘附因子ICAM-1 及血管細胞粘附因子VCAM-1)的表達。同時,MDP能顯著促進共培養體系中炎症相關細胞因子IL-6,趨化因子CXCL8及抗菌肽β-防禦素2的釋放。在MDP刺激下,支氣管上皮細胞是共培養體系中釋放IL-6,CXCL8及β-防禦素2的主要細胞。在MDP刺激下,嗜鹼性粒細胞中包括胞核因子-kappaB(NF-κB)在內的幾個核轉錄因子的表達上升。ICAM-1,VCAM-1,IL-6,CXCL8,及β-防禦素2的表達被信號分子化學抑制劑所抑制,結果表明,嗜鹼性粒細胞與支氣管上皮細胞的相互作用受不同的信號通路(NF-κB, p38 MAPK 及 JNK)調節。OVA致敏小鼠實驗表明,NLR配體能增加分泌粘蛋白的杯狀細胞在肺氣管中的數量,使小鼠支氣管下皮結締組織纖維化並增厚。NLR配體進而提高過敏性哮喘小鼠支氣管肺泡灌洗液中CCL5與IL-13 的表達水平。 / 研究表明,在嗜鹼性粒細胞和皮膚成纖維細胞的共培養體系中,HKSA,MDP,PGN,LTA,或Pam3CSK4顯著誘導ICAM-1, IL-6, CXCL8, CCL2 和 CCL5 的表達。而嗜鹼性粒細胞與皮膚成纖維細胞的直接相互作用是釋放IL-6, CXCL8, CCL2 與 CCL5 所必需的。嗜鹼性粒細胞與皮膚成纖維細胞的相互作用並釋放細胞因子與趨化因子受p38 MAPK 及 NF-κB信號通路調控。 / 在嗜鹼性粒細胞與支氣管上皮細胞共培養體系中,LIGHT 可能通過受體HVEM 與 LTβR顯著增強支氣管上皮細胞表面粘附因子的表達,提高細胞因子IL-6, CXCL8 與 MMP-9的釋放。 / 研究結果表明,在過敏炎症中,通過與組織細胞(如支氣管上皮細胞,人皮膚成纖維細胞)相互作用,嗜鹼性粒細胞有利於組織細胞對病原相關的分子模式作出反應。因此,研究結果對細菌介導的先天性免疫應答與過敏炎症的加重之間的聯繫作出了新的解釋。以上結果也增強了我們對LIGHT在氣道重塑中的免疫病理作用及其作為氣道重塑治療靶標的認識。 / The incidences of allergic diseases such as allergic asthma and atopic dermatitis (AD) are increasing in Hong Kong and worldwide. Allergic asthma is a chronically relapsing inflammatory pulmonary disease, while AD is a chronic inflammatory skin disorder. Respiratory bacterial and Staphylococcus aureus (S. aureus) infection can provoke allergen sensitization and subsequently amplify and sustain inflammation in allergic asthma and AD, respectively. The innate immune system recognizes bacterial infection through pattern recognition receptors (PRRs), two important PRRs involving in inflammatory and immune responses are nucleotide-binding oligomerization domain-like receptors (NLRs) and Toll-like receptors (TLRs). NOD2 is one member of the NLR family, which senses the conserved structural component muramyl dipeptide (MDP) in almost all bacteria. TLR2 recognizes a wide range of pathogen-associated molecular patterns (PAMPs) including peptidoglycan (PGN) and lipoteichoic acid (LTA) from Gram-positive bacteria and synthetic triacylated lipoprotein N-palmitoyl-S-[2,3-bis (palmitoyloxy)-(2RS)-propyl]-[R]-cysteinyl-[S]-seryl-[S]-lysyl-[S]-lysyl-[S]-lysyl-[S] -lysine (Pam3CSK4). / In the present study, we investigated the effect of NOD2 ligand MDP, asthma-related tumor necrosis factor (TNF) family member LIGHT on human basophils co-cultured with human bronchial epithelial cells and the effect of heat-killed S. aureus, MDP, TLR2 ligands PGN, LTA and Pam3CSK4 on basophils co-cultured with human dermal fibroblasts, and the underlying intracellular mechanisms. The in vivo effect of NOD ligands on ovalbumin (OVA)-sensitized allergic asthmatic mice was also studied. / It was found that MDP could significantly enhance the cell surface expression of adhesion molecules intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on basophils and primary human bronchial epithelial cells (HBE) in the co-culture system (all p < 0.05). MDP could further enhance the release of inflammatory cytokine interleukin (IL)-6, chemokine CXCL8, and epithelium derived anti-microbial peptide β-defensin 2 in the co-culture. HBE cells were the major source while basophils were the minor source to release IL-6, CXCL8 and β-defensin 2 in the co-culture upon MDP stimulation. The activities of several nuclear transcription factors, including NF-κB, were up-regulated in human basophils upon MDP stimulation. The cell surface expression of ICAM-1 and VCAM-1 and the release of IL-6, CXCL8 and β-defensin 2 were suppressed by the signaling molecule inhibitors, implying that the interaction between basophils and primary human bronchial epithelial cells could be differentially regulated by the NF-κB, p38 MAPK and JNK pathways. The animal study showed that iE-DAP and MDP could increase the number of mucin-secreting goblet cells, the thickness and fibrosis of the bronchial subepithelial tissue of airways from the OVA-sensitized mice. The iE-DAP and MDP could further promote the levels of CCL5 and IL-13 (all p < 0.05) in bronchoalveolar lavage fluid (BALF) of allergic asthmatic mice. / It was found that the induction of ICAM-1, IL-6, CXCL8, CCL2 and CCL5 was significantly promoted upon the interaction between human basophils and dermal fibroblasts activated by heat-killed S. aureus, MDP, PGN, LTA or Pam3CSK4. The release of IL-6, CXCL8, CCL2 and CCL5 might depend on the direct interaction of basophils and dermal fibroblasts. The p38 MAPK and NF-κB pathways should be involved in the release of the cytokines and chemokines upon the interaction of basophils and human dermal fibroblasts. / LIGHT could significantly promote the cell surface expression of adhesion molecule, the release of IL-6, CXCL8 and MMP-9 from human bronchial epithelial cells upon the interaction with basophils, probably through the receptors HVEM and LTβR. / The results suggest that, through the interaction with tissue-resident cells such as bronchial epithelial cells and dermal fibroblasts, basophils may facilitate the activation of tissue-resident cells in response to the PAMPs in allergic inflammation. The results therefore provide a new insight of the crucial link between the bacterial-mediated innate immune response and the exacerbation of allergic inflammation. The above results also enhance our understanding on the immunopathological roles of LIGHT in airway remodeling, and the potential therapeutic target for airway remodeling. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Qiu, Huaina. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 165-196). / Abstract also in Chinese. / Acknowledgements --- p.i / Abbreviations --- p.iii / Abstract --- p.vi / 摘要 --- p.ix / Publications --- p.xi / Table of Contents --- p.xiii / Chapter Chapter 1: --- General Introduction --- p.1 / Chapter 1.1 --- Asthma and atopic dermatitis (AD) --- p.1 / Chapter 1.2 --- Human basophils in allergic inflammation --- p.3 / Chapter 1.2.1 --- Development and morphology of basophils --- p.3 / Chapter 1.2.2 --- Receptors and products of basophils --- p.4 / Chapter 1.2.3 --- Cell surface markers on basophils --- p.7 / Chapter 1.2.4 --- Basophils in allergic inflammation --- p.7 / Chapter 1.3 --- Human bronchial epithelial cells in airway inflammation --- p.10 / Chapter 1.4 --- Human fibroblasts in AD --- p.11 / Chapter 1.5 --- Staphylococcus aureus (S. aureus) in AD --- p.12 / Chapter 1.6 --- NOD2 and TLR2 in allergic inflammation --- p.14 / Chapter 1.7 --- IL-33 in allergic inflammation --- p.18 / Chapter 1.8 --- IL-6 in allergic inflammation --- p.18 / Chapter 1.9 --- CXCL8 in allergic inflammation --- p.20 / Chapter 1.10 --- CCL2 in allergic inflammation --- p.21 / Chapter 1.11 --- CCL5 in allergic inflammation --- p.22 / Chapter 1.12 --- β-defensin 2 (HBD-2) in allergic inflammation --- p.23 / Chapter 1.13 --- ICAM-1 and VCAM-1 in allergic inflammation --- p.25 / Chapter 1.14 --- LIGHT and airway remodeling in allergic asthma --- p.25 / Chapter 1.15 --- Signal transduction pathways in allergic inflammation and pharmacological inhibitors --- p.26 / Chapter 1.15.1 --- Signal transduction pathways in allergic inflammation --- p.26 / Chapter 1.15.2 --- Signaling molecule inhibitors as new drugs for inflammatory diseases --- p.31 / Chapter 1.16 --- Aims and scope of the study --- p.32 / Chapter Chapter 2: --- Materials and Methods --- p.35 / Chapter 2.1 --- Materials --- p.35 / Chapter 2.1.1 --- Reagents and buffers for the purification of human basophils --- p.35 / Chapter 2.1.2 --- Primary cells and cell lines --- p.36 / Chapter 2.1.3 --- Heat-killed Staphyloccocus aureus (HKSA) --- p.38 / Chapter 2.1.4 --- Ligands for NLR and TLR2 --- p.39 / Chapter 2.1.5 --- Recombinant human cytokines --- p.39 / Chapter 2.1.6 --- Reagents and buffer solutions for flow cytometry --- p.40 / Chapter 2.1.7 --- RNA extraction, reverse transcription-polymerase chain reaction (RT-PCR), and real-time quantitative PCR (qPCR) --- p.45 / Chapter 2.1.8 --- Cytometric Bead Array (CBA) Kits --- p.48 / Chapter 2.1.9 --- MILLIPLEX® MAP Human Cytokine/Chemokine Magnetic Bead Panel Kit --- p.49 / Chapter 2.1.10 --- Enzyme-linked immunosorbent assay (ELISA) kits --- p.49 / Chapter 2.1.11 --- Procarta Transcription Factor Assay kit --- p.50 / Chapter 2.1.12 --- Signal transduction inhibitors --- p.50 / Chapter 2.2 --- Methods --- p.50 / Chapter 2.2.1 --- Purification of primary human basophils and basophil culture --- p.50 / Chapter 2.2.2 --- Culture of KU812 cells --- p.51 / Chapter 2.2.3 --- Culture of primary human bronchial epithelial cells --- p.51 / Chapter 2.2.4 --- Culture of BEAS-2B cells --- p.52 / Chapter 2.2.5 --- Culture of human dermal fibroblasts --- p.52 / Chapter 2.2.6 --- Co-culture of primary human bronchial epithelial cells/human bronchial epithelial cell line (BEAS-2B) cells and basophils/KU812 cells --- p.52 / Chapter 2.2.7 --- Co-culture of human dermal fibroblasts and basophils/KU812 cells --- p.52 / Chapter 2.2.8 --- Co-culture of fixed primary human bronchial epithelial cells and basophils --- p.53 / Chapter 2.2.9 --- Co-culture of human dermal fibroblasts and basophils in the presence of transwell inserts --- p.53 / Chapter 2.2.10 --- CBA assay --- p.53 / Chapter 2.2.11 --- ELISA --- p.54 / Chapter 2.2.12 --- Human Transcription Factor Plex Assay --- p.54 / Chapter 2.2.13 --- Milliplex Human Cytokine / Chemokine Magnetic Panel assay --- p.54 / Chapter 2.2.14 --- Bio-Plex mouse cytokine assay --- p.55 / Chapter 2.2.15 --- Flow cytometric analysis of cell surface expression of target molecules --- p.55 / Chapter 2.2.16 --- Flow cytometric analysis of intracellular expression of target molecules --- p.55 / Chapter 2.2.17 --- Allergic asthmatic mice model --- p.57 / Chapter 2.2.18 --- Statistical analysis --- p.57 / Chapter Chapter 3: --- Muramyl Dipeptide Mediated Activation of Human Bronchial Epithelial Cells Interacting with Basophils: A Novel Mechanism of Airway Inflammation --- p.59 / Chapter 3.1 --- Introduction --- p.59 / Chapter 3.2 --- Results --- p.61 / Chapter 3.2.1 --- Cell surface expression of CD203c on basophils --- p.61 / Chapter 3.2.2 --- Intracellular expression of NOD2 protein --- p.63 / Chapter 3.2.3 --- Cell surface expression of adhesion molecules on basophils and primary human bronchial epithelial cells activated by MDP --- p.67 / Chapter 3.2.4 --- Induction of cytokine, chemokine and β-defensin 2 upon the interaction of basophils and bronchial epithelial cells stimulated by MDP --- p.71 / Chapter 3.2.5 --- Bronchial epithelial cells were the main source for the release of IL-6, CXCL8 and β-defensin 2 in co-culture --- p.74 / Chapter 3.2.6 --- Effects of signaling inhibitors on MDP-induced cytokines and adhesion molecules --- p.77 / Chapter 3.2.7 --- Differential activation of intracellular signaling pathways involved in the interaction of KU812 and BEAS-2B upon MDP stimulation --- p.84 / Chapter 3.2.8 --- In vivo effect of NOD1,2 ligands on IgE and chemokine production in serum and BALF in allergic asthmatic mice --- p.89 / Chapter 3.3 --- Discussion --- p.93 / Chapter Chapter 4: --- NOD2 and TLR2 Ligands Mediated Activation of Basophils Interacting with Human Dermal Fibroblasts in Atopic Dermatitis --- p.100 / Chapter 4.1 --- Introduction --- p.100 / Chapter 4.2 --- Results --- p.102 / Chapter 4.2.1 --- Cell surface expression of adhesion molecules ICAM-1 on human dermal fibroblasts activated by heat-killed Staphyloccocus aureus (HKSA) --- p.102 / Chapter 4.2.2 --- Induction of chemokines upon the interaction of basophils and human dermal fibroblasts stimulated by HKSA --- p.104 / Chapter 4.2.3 --- Expression of NOD2 and TLR2 protein --- p.107 / Chapter 4.2.4 --- Cell surface expression of adhesion molecule ICAM-1 on human dermal fibroblasts activated by MDP, PGN, LTA or Pam3CSK4 --- p.110 / Chapter 4.2.5 --- Induction of cytokine and chemokines upon the interaction of basophils (with or without IL-33 priming) and human dermal fibroblasts stimulated by MDP, PGN, LTA or Pam3CSK4 --- p.112 / Chapter 4.2.6 --- Direct interaction between human dermal fibroblasts and basophils was required for the release of IL-6, CXCL8, CCL2 and CCL5 upon the stimulation of MDP, PGN, LTA and Pam3CSK4 --- p.118 / Chapter 4.2.7 --- Effect of signaling molecular inhibitors on the expression of adhesion molecule ICAM-1 --- p.121 / Chapter 4.2.8 --- Effect of signaling molecule inhibitors on the release of cytokine and chemokines upon the stimulation by NOD2 and TLR2 ligands --- p.123 / Chapter 4.2.9 --- Differential activation of intracellular signaling pathways involved in the interaction of human dermal fibroblasts and basophilic KU812 upon stimulation of NOD2 and TLR2 ligands --- p.127 / Chapter 4.3 --- Discussion --- p.131 / Chapter Chapter 5: --- Effect of Tumor Necrosis Factor Family Member LIGHT on the Activation of Basophils Interacting with Bronchial Epithelial Cells: Potential Therapeutic Target for Airway Remodeling --- p.138 / Chapter 5.1 --- Introduction --- p.138 / Chapter 5.2 --- Results --- p.139 / Chapter 5.2.1 --- Cell surface expression of HVEM and LTβR --- p.139 / Chapter 5.2.2 --- Effect of LIGHT on the expression of ICAM-1 on basophil or BEAS-2B alone or co-culture --- p.141 / Chapter 5.2.3 --- Induction of cytokine and chemokine upon the interaction of basophils and BEAS-2B cells stimulated by LIGHT --- p.144 / Chapter 5.2.4 --- Induction of MMP-9 upon the interaction of basophils and BEAS-2B cells stimulated by LIGHT --- p.147 / Chapter 5.2.5 --- Effect of LIGHT on the release of TGFβ-1, histamine and periostin upon the interaction of basophils and BEAS-2B cells --- p.149 / Chapter 5.3 --- Discussion --- p.152 / Chapter Chapter 6: --- Conclusion and Future Perspectives --- p.156 / Chapter 6.1 --- General conclusions --- p.156 / Chapter 6.2 --- Future perspectives --- p.160 / Appendix --- p.163 / References --- p.165
3

Chlamydia pneumoniae and airways inflammation : an investigation of the host cell-pathogen relationship / Tracy Renee McNamara.

McNamara, Tracy Renee January 2004 (has links)
"December 2004" / Includes bibliographical references (leaves 342-379) / xiii, 379 leaves : ill. (col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Medicine, 2005

Page generated in 0.1203 seconds