Co-culture of eosinophils and BEAS-2B cells was found to increase the release of cytokine IL-6 and chemokines MIG, MCP-1, IL-8 and IP-10 and up-regulate the corresponding genes expression in BEAS-2B cells or eosinophils. Interaction of eosinophil-BEAS-2B cells could also elevate adhesion molecules ICAM-1, VCAM-1, ICAM-3, and CD49d expression on the surface of BEAS-2B cells, and CD18 and ICAM-3 on eosinophils, and up-regulate ICAM-1 gene expression in BEAS-2B cells. Lipopolysaccharide (LPS) and tumor necrosis factor (TNF)-alpha could induce or further induce ICAM-1 expression on eosinophils and BEAS-2B cells upon their interaction. Moreover, activities of both NF-kappaB and p38 MAPK in BEAS-2B cells were markedly elevated after co-cultured with eosinophils. / Freshly isolated eosinophils from human peripheral blood and confluent BEAS-2B cells were co-cultured together in tissue culture plate for a pre-determined time period. Cytokines including interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-10, IL-12p70, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma and chemokines regulated upon activation normal T cell expressed and secreted (RANTES), monokine induced by interferon-gamma (MIG), monocyte chemoattractant protein (MCP)-1, IL-8, and interferon inducible protein (IP)-10 in culture supernatant were evaluated by protein array and quantified by cytometric bead array (CBA) kit of Th1/Th2 cytokines, inflammatory cytokines, and human chemokines using flow cytometry and enzyme linked immunosorbent assay (ELISA) kit. / In order to investigate the immunopathological mechanism in allergic asthma of eosinophils interacting with bronchial epithelium in inflammation site, a in vitro system of co-culture of human bronchial epithelial cells and eosinophils was set up to mimic the inflammatory reaction. / In summary, co-culture of epithelial cells, BEAS-2B cells, and eosinophils could activate NF-kappaB and p38 MAPK signal transduction pathways to induce inflammatory cytokine IL-6, and chemokines IL-8, MCP-1, MIG and IP-10 release in culture supernatant, and up-regulated the expression of surface adhesion molecules ICAM-1, VCAM-1, ICAM-3 and CD49d protein on BEAS-2B, and CD18 and ICAM-3 on eosinophils. (Abstract shortened by UMI.) / In this study, co-culture of a human epithelial cell line, BEAS-2B cells, and peripheral eosinophils was adopted as an in vitro model to investigate the effect of interaction of epithelial cells and eosinophils in airways on pathophysiology of asthma. / Wang Chengbin. / "July 2005." / Advisers: Wai kei Lam; Chun kwok Wong; Yaping Tian. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3723. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 119-134). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

O parênquima pulmonar periférico tem sido estudado como um componente da resposta inflamatória na asma. Durante uma constrição induzida, a resistência do tecido aumenta em diferentes modelos de asma. Aproximadamente 60% dos pacientes asmáticos possuem respostas imediata e tardia. A resposta tardia é caracterizada por obstrução mais grave de vias aéreas. No presente estudo, foi avaliada a mecânica de fatias de parênquima pulmonar em cobaias sensibilizadas com ovoalbumina (OVA), tentando reproduzir ambas as repostas imediata e tardia. A mecânica oscilatória de fatias pulmonares foi realizada em um grupo controle (C), em um grupo de resposta imediata (IM) e em dois grupos de resposta tardia: 17 (T1) e 72 (T2) horas após o último desafio com ovoalbumina. Medidas de resistência (R) e elastância (E) foram obtidas antes e depois do desafio com OVA nos grupos C e IM e antes e depois do desafio com Acetilcolina (ACh) em todos os grupos. Com o uso de morfometria, foram avaliadas as densidades de eosinófilos e de células musculares lisas, assim como o conteúdo de colágeno e elastina nas fatias pulmonares. Os valores de R e E basais e pós-agonista estão aumentados nos grupos IM, T1 e T2 quando comparados com o grupo C (p = 0.001). A análise morfométrica mostrou um aumento na densidade de eosinófilos nas fatias de tecido periférico dos grupos IM e T2 quando comparados com o grupo C (p < 0.05). Houve uma correlação positiva significante entre a densidade de eosinófilos nas fatias de parênquima dos grupos C, T1 e T2 e os valores de R e E pós-ACh (r = 0,71, p = 0.001 e r = 0,74, p < 0.001, respectivamente). Os resultados mostram que o parênquima pulmonar está envolvido na resposta tardia deste modelo de inflamação alérgica crônica e que a resposta constritora nesta fase está relacionada à inflamação eosinofílica. / The peripheral lung parenchyma has been studied as a component of the asthmatic inflammatory response. During induced constriction, tissue resistance increases in different asthma models. Approximately 60% of the asthmatic patients show early and late responses. The late response is characterized by more severe airway obstruction. In the present study, we evaluated lung parenchymal strips mechanics in ovalbumin-sensitized guinea pigs, trying to reproduce both early and late inflammatory responses. Oscillatory mechanics of lung strips were performed in a control group (C), in an early response group (ER), and in two late response groups: 17 (L1) and 72 (L2) hours after the last ovalbumin challenge. Measurements of resistance and elastance were obtained before and after ovalbumin challenge in C and ER groups and before and after Acetylcholine challenge in all groups. Using morphometry, we assessed the density of eosinophils and smooth muscle cells, as well as collagen and elastin content in lung strips. The baseline and post-agonist values of resistance and elastance were increased in ER, L1 and L2 groups compared with C (p = 0.001). The morphometric analysis showed an increase in alveolar eosinophil density in ER and L2 groups compared with C group (p < 0.05). There was a significant correlation between eosinophil density in parenchymal strips of C, L1 and L2 groups and values of resistance and elastance post-Acetylcholine (r = 0.71, p = 0.001 and r=0.74, p < 0.001, respectively). The results show that the lung parenchyma is involved in the late response of this guinea pig model of chronic allergic inflammation and the constriction response in this phase is related to the eosinophilic inflammation.

Background: Asthma is characterized by chronic airway inflammation in which leukocytes are attracted into the inflamed airway under the influence of chemokines. Molecular studies and allergen bronchoprovocation suggested that chemokines such as thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), eotaxin and regulated upon activation normal T-cell expressed and secreted (RANTES) were involved in the airway responses to allergen exposure. / Conclusions: Chemokines are important mediators in the pathophysiology of asthma and atopy. TARC in plasma and MDC in EBC appear to be useful biomarkers for assessing childhood asthma. Besides, MDC concentrations in UCB may predict the susceptibility to develop wheezing during infancy. / Methods: Asthmatic patients, non-allergic controls and healthy singleton newborns were recruited from attendants of a university teaching hospital. Atopy-related chemokines in peripheral blood and EBC were measured by enzyme-linked immunosorbent assays. Genomic DNA from asthmatics and controls was genotyped by restriction fragment length polymorphism to characterize single nucleotide polymorphisms (SNPs) in the genes encoding TARC, RANTES, interleukin-13 and CD14. / Objectives: This thesis investigated the relation between chemokines and asthma and atopy by: (a) measuring their concentrations in peripheral blood and exhaled breath condensate (EBC); (b) performing case-control association studies for genes encoding atopy-related chemokines and related molecules; and (c) analyzing chemokines in umbilical cord blood (UCB) in relation to wheezing phenotypes during infancy. / Results: Plasma TARC concentrations were higher in children with chronic asthma than controls, and also correlated with plasma total IgE. Among children with asthmatic exacerbation, plasma TARC concentrations showed inverse correlation with peak expiratory flow rates at presentation. When measured in EBC, MDC but not TARC or eotaxin was higher in asthmatics than controls. In our genetic association studies, SNPs in IL13, RANTES and TARC were associated with serum total and/or allergen-specific IgE. TARC C-431T was also linked to peripheral eosinophilia. However, none of these polymorphisms was associated with physician-diagnosed asthma. Interestingly, C-159T in CD14 was also associated with serum total IgE, but only among atopic asthmatic children. In the last part involving 124 singleton healthy newborns, MDC concentrations in UCB were significantly increased in newborns who wheezed during infancy. / Leung Ting-fan. / Adviser: Gary W.K. Wong. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (M.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 196-231). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.

Mast cells are pivotal effector cells in the pathogenesis of allergic and inflammatory diseases. Activation of FcepsilonRI in mast cells by antigen initiates a complex series of biochemical events leading to the release and synthesis of myriads of chemical mediators and cytokines. Adenosine is an endogenous nucleoside formed from cleavage of AMP by the enzyme 5'-nucleotidase. It exerts modulating effects in a large number of cellular systems by acting through four distinct subtypes of adenosine receptors (A1, A 2A, A2B and A3) which belong to the G-protein-coupled receptor (GPCR) family. Increasing evidence have been provided to show that adenosine plays a role in the pathophysiology of asthma through a mast cell dependent mechanism. / Pharmacological studies using specific adenosine agonists and antagonists revealed that A1 receptor was responsible for the potentiating effect of adenosine with the involvement of the pertussis toxin-sensitive Galphai-protein. Conversely, inhibition of HCMC activation was mediated by A2B receptor and was accompanied by the elevation of cAMP level suggesting the participation of Galphas-protein. / Taken together, the current studies explored the dual effect of adenosine on human mast cells activation which enhanced our understanding of adenosine receptor biology. The effectiveness of adenosine in modulating the important mast cell activation pathways definitely facilitates the rational exploitation of these receptors as therapeutic targets that could be converted into clinical benefits for asthmatic patients. / To better characterize the effect of adenosine on human mast cell under asthmatic environment, we incubated HCMC under different inflammatory condition found in asthmatic, including toll-like receptor (TLR) ligands and inflammatory cytokines. Functional studies on mediator release from HCMC indicated that out of all tested substances, Peptidoglycan (PGN) pre-incubation enhanced the IL-8 synthesis from HCMC in response to low concentration of adenosine (10-9--10-7 M). / We also investigated the action of adenosine on key signal transduction pathways involved in mast cells activation. Study on intracellular calcium concentration ([Ca2+]i) revealed that low concentration of adenosine (10-8 M) through activation of PI3Kgamma significantly enhanced Ca2+ influx. In contrast, high concentration of adenosine at 10-4 M substantially inhibited [Ca2+] i in response to anti-IgE. Furthermore, investigation on intracellular signaling molecules provided evidence that adenosine at concentrations over 10-6 M does-dependently inhibited the immunoglobulin (IgE)-dependent activation of ERK, JNK or NF-kappaB pathways, whereas enhancement of IkappaBalpha was found on low concentration of adenosine. The above observation help to justify the dual action of adenosine on anti-IgE-induced mediators release from HCMC. Our investigation further suggested that adenosine may inhibit HCMC activation through a novel cAMP-dependent, but PKA- and EPAC-independent, signaling pathway. / We generated human cultured mast cells (HCMC) from human buffy coat and confirmed the expression of all adenosine receptor subtypes in them. We showed that adenosine alone did not induce HCMC degranulation and cytokine release. However, adenosine and the non-selective agonist, 5'-N-Ethylcarbox-amidoadenosine (NECA), produced a biphasic response on anti-IgE induced mast cell activation. An enhancement of HCMC activation was observed with low concentrations of adenosine and NECA (10-9--10-7 M), whereas a predominant inhibitory action was observed at concentrations higher than 10-6 M. / Yip, Kwok Ho. / Adviser: Alaster H.Y. Lau. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 237-263). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

O parênquima pulmonar periférico tem sido estudado como um componente da resposta inflamatória na asma. Durante uma constrição induzida, a resistência do tecido aumenta em diferentes modelos de asma. Aproximadamente 60% dos pacientes asmáticos possuem respostas imediata e tardia. A resposta tardia é caracterizada por obstrução mais grave de vias aéreas. No presente estudo, foi avaliada a mecânica de fatias de parênquima pulmonar em cobaias sensibilizadas com ovoalbumina (OVA), tentando reproduzir ambas as repostas imediata e tardia. A mecânica oscilatória de fatias pulmonares foi realizada em um grupo controle (C), em um grupo de resposta imediata (IM) e em dois grupos de resposta tardia: 17 (T1) e 72 (T2) horas após o último desafio com ovoalbumina. Medidas de resistência (R) e elastância (E) foram obtidas antes e depois do desafio com OVA nos grupos C e IM e antes e depois do desafio com Acetilcolina (ACh) em todos os grupos. Com o uso de morfometria, foram avaliadas as densidades de eosinófilos e de células musculares lisas, assim como o conteúdo de colágeno e elastina nas fatias pulmonares. Os valores de R e E basais e pós-agonista estão aumentados nos grupos IM, T1 e T2 quando comparados com o grupo C (p = 0.001). A análise morfométrica mostrou um aumento na densidade de eosinófilos nas fatias de tecido periférico dos grupos IM e T2 quando comparados com o grupo C (p < 0.05). Houve uma correlação positiva significante entre a densidade de eosinófilos nas fatias de parênquima dos grupos C, T1 e T2 e os valores de R e E pós-ACh (r = 0,71, p = 0.001 e r = 0,74, p < 0.001, respectivamente). Os resultados mostram que o parênquima pulmonar está envolvido na resposta tardia deste modelo de inflamação alérgica crônica e que a resposta constritora nesta fase está relacionada à inflamação eosinofílica. / The peripheral lung parenchyma has been studied as a component of the asthmatic inflammatory response. During induced constriction, tissue resistance increases in different asthma models. Approximately 60% of the asthmatic patients show early and late responses. The late response is characterized by more severe airway obstruction. In the present study, we evaluated lung parenchymal strips mechanics in ovalbumin-sensitized guinea pigs, trying to reproduce both early and late inflammatory responses. Oscillatory mechanics of lung strips were performed in a control group (C), in an early response group (ER), and in two late response groups: 17 (L1) and 72 (L2) hours after the last ovalbumin challenge. Measurements of resistance and elastance were obtained before and after ovalbumin challenge in C and ER groups and before and after Acetylcholine challenge in all groups. Using morphometry, we assessed the density of eosinophils and smooth muscle cells, as well as collagen and elastin content in lung strips. The baseline and post-agonist values of resistance and elastance were increased in ER, L1 and L2 groups compared with C (p = 0.001). The morphometric analysis showed an increase in alveolar eosinophil density in ER and L2 groups compared with C group (p < 0.05). There was a significant correlation between eosinophil density in parenchymal strips of C, L1 and L2 groups and values of resistance and elastance post-Acetylcholine (r = 0.71, p = 0.001 and r=0.74, p < 0.001, respectively). The results show that the lung parenchyma is involved in the late response of this guinea pig model of chronic allergic inflammation and the constriction response in this phase is related to the eosinophilic inflammation.

Airway remodeling in asthma includes alterations in extracellular matrix and airway smooth muscle (ASM) mass. For this study, ASM cells were obtained from rats that were challenged with ovalbumin (OVA) or saline (SAL) as control. OVA and SAL cells were seeded on plastic control (PC) or on plates coated with decorin or biglycan. OVA cell number was significantly increased versus SAL cells, for cells seeded on PC (48 h). A significant decrease in cell number was observed for both OVA and SAL cells seeded on decorin compared to PC cells (48 h). OVA cells, however, showed a more modest reduction in cell number. Furthermore, biglycan decreased SAL cell number only. Compared to no strain (NS), mechanical strain (S) reduced cell number for OVA and SAL cells on all matrices. In addition, S up-regulated expression of beta 1-integrin relative to NS controls. Results suggest an ability of ASM cells to be modulated by matrix and mechanical stimulation.

The increase in ASMC mass is a major structural change described in airway remodeling in asthma. This increase has been attributed to ASMC hyperplasia and hypertrophy. The distance between ASMC and the epithelium is reduced suggesting expansion of the muscle bundle towards the epithelium. Recent studies have suggested a role of epithelial derived chemokines in ASMC migration toward the epithelium. We hypothesized that chemokines (Eotaxin, RANTES, MIP-1alpha and IL-8) can directly influence ASMC mass by increasing the rate of proliferation or enhancing survival. ASMCs were exposed to different concentrations of eotaxin, RANTES, IL-8 or MIP-1alpha. To test for proliferation, stimulated ASMC were pulsed with 3H-thymidine or stained with BrdU and then analyzed with flow cytometry. Apoptosis was measured using Annexin V and flow cytometry. Expression of phosphorylated p42/p44 and MAPKinases was assessed by Western analysis. In a concentration-dependent manner, chemokines such as Eotaxin, RANTES, IL-8 and MIP-lalpha increased ASMCs 3H-thymidine incorporation and DNA synthesis. Eotaxin, RANTES and IL-8 decreased the number of apoptotic ASMCs compared to the matched controls. A significant increase in phosphorylated p42/p44 MAPKs was seen after treating ASMCs with RANTES and eotaxin. We conclude that chemokines might contribute to airway remodeling by increasing the number of ASMCs.

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Wong, Yun Sze. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 142-162). / Abstracts in English and Chinese. / Abstract (in English) --- p.ii / Abstract (in Chinese) --- p.vi / Acknowledgement --- p.ix / Statement of Work --- p.x / Table of Contents --- p.xi / List of Tables --- p.xiv / List of Figures --- p.xvi / Glossary of Terms and Abbreviations --- p.xviii / Chapter Section I: --- Introduction --- p.1 / Chapter Chapter 1: --- General Overview of Asthma --- p.2 / Chapter 1.1 --- Asthma definition and its phenotype --- p.2 / Chapter 1.2 --- Asthma epidemiology and its prevalence in past decades --- p.4 / Chapter 1.3 --- Hygiene hypothesis and asthma development --- p.8 / Chapter 1.4 --- Asthma pathogenesis and innate immunity --- p.12 / Chapter 1.5 --- The environmental factors and genetic makeup in relation with asthma --- p.17 / Chapter Chapter 2: --- Study Plan and Obj ective --- p.21 / Chapter Section II: --- Literature Review --- p.24 / Chapter Chapter 3: --- Indoor Environmental factors of Asthma --- p.25 / Chapter 3.1 --- Overview of the indoor environmental factors --- p.25 / Chapter 3.2 --- House dust endotoxin --- p.27 / Chapter 3.2.1 --- Determinants of endotoxin exposure in home environment --- p.21 / Chapter 3.2.2 --- Protective role of endotoxin in allergy and asthma development --- p.29 / Chapter 3.2.3 --- Deleterious effect of endotoxin exposure in asthma: the dark side --- p.31 / Chapter 3.3 --- Allergen --- p.34 / Chapter 3.3.1 --- Allergens: an update --- p.34 / Chapter 3.3.2 --- Determinants of allergens in home environment --- p.35 / Chapter 3.3.3 --- Allergens avoidance: environmental intervention --- p.36 / Chapter 3.4 --- Nitrogen dioxide --- p.40 / Chapter 3.4.1 --- Determinants of indoor nitrogen dioxide and its relation with gas cooking --- p.40 / Chapter 3.4.2 --- The adverse effects of nitrogen dioxide on respiratory symptoms --- p.41 / Chapter 3.4.3 --- Reactive nitrogen species and nitrosative stress in asthma --- p.42 / Chapter Chapter 4: --- CD14 Single Nucleotide Polymorphisms and Asthma --- p.45 / Chapter 4.1 --- Overview of CD14 receptor --- p.45 / Chapter 4.2 --- Action of CD14 receptor in endotoxin response --- p.47 / Chapter 4.3 --- Relation of CD14 with asthma --- p.48 / Chapter 4.3.1 --- Associations between CD14 polymorphisms and asthma phenotypes --- p.48 / Chapter 4.3.2 --- Endotoxin switch concept: from gene to gene - environment --- p.52 / Chapter Section III: --- Study Core --- p.55 / Chapter Chapter 5: --- Methodology in indoor environment investigation and its result --- p.57 / Chapter 5.1 --- Study Population --- p.57 / Chapter 5.2 --- Home Visiting Protocol --- p.60 / Chapter 5.2.1 --- The International Study of Asthma and Allergies in Childhood (ISAAC) --- p.60 / Chapter 5.2.2 --- ISAAC questionnaire --- p.61 / Chapter 5.2.3 --- House dust collection procedures --- p.62 / Chapter 5.2.4 --- Indoor nitrogen dioxide measurements --- p.65 / Chapter 5.2.4.1 --- Ogawa passive sampler --- p.65 / Chapter 5.2.4.2 --- Preparation and measurement procedures --- p.66 / Chapter 5.2.4.3 --- Indoor nitrogen dioxide quantification --- p.67 / Chapter 5.3 --- House dust extraction --- p.69 / Chapter 5.4 --- House dust endotoxin measurement --- p.70 / Chapter 5.5 --- Allergen measurement --- p.72 / Chapter 5.6 --- Statistical Analysis --- p.75 / Chapter 5.7 --- Results --- p.77 / Chapter 5.7.1 --- Demographic data and subjects characteristics --- p.77 / Chapter 5.7.2 --- "Dust weight, endotoxin and allergen levels and their determinants in household" --- p.82 / Chapter 5.7.3 --- Indoor NO〕2levels and its determinant in household --- p.95 / Chapter 5.7.4 --- Associations between indoor environmental factors and respiratory health --- p.96 / Chapter 5.7.4.1 --- Clinical symptoms --- p.96 / Chapter 5.7.4.2 --- Exhaled NO levels --- p.101 / Chapter 5.7.4.3 --- Spirometric indices --- p.103 / Chapter Chapter 6： --- Methodology in genotyping CD14 polymorphisms and its result --- p.105 / Chapter 6.1 --- Study population --- p.105 / Chapter 6.2 --- Serum Total and allergen-specific IgE measurement --- p.106 / Chapter 6.3 --- CD14 Genotyping s --- p.107 / Chapter 6.3.1 --- Genotyping promoter SNPs ofCD14/-159 and -1359 --- p.107 / Chapter 6.3.2 --- Genotyping promoter SNP of CD14/-1619 --- p.109 / Chapter 6.3.3 --- Validation of genotyping by sequencing --- p.111 / Chapter 6.4 --- Statistical Analysis --- p.112 / Chapter 6.5 --- Results --- p.113 / Chapter 6.5.1 --- Subjects characteristics and clinical features. --- p.113 / Chapter 6.5.2 --- Associations between CD14 SNPs and asthma phenotypes --- p.114 / Chapter Chapter 7: --- Discussion --- p.120 / Chapter 7.1 --- Influence of indoor factors on asthmatic children --- p.120 / Chapter 7.2 --- CD14 polymorphisms in modifying asthma phenotypes --- p.135 / Chapter Chapter 8: --- Conclusion and Further Works --- p.138 / References --- p.141 / Appendix 1 Questionnaire / Appendix 2 Publications